Effect of Horizontal Geometric Irregularity on a High Rise RC Structure

Effect of Horizontal Geometric Irregularity on a High Rise RC Structure | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Effect of Horizontal Geometric Irregularity on a High Rise RC Structure Ms Sanija Jalindar Patil, Dr. Mrudula Kulkarni This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7438879/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The seismic performance of reinforced concrete (RC) structures is highly sensitive to their geometric configuration, both in plan and elevation. Among these, horizontal geometric irregularity— manifested in forms such as L-shaped, T-shaped, and Ushaped plans, re-entrant corners, diaphragm discontinuities, and torsional eccentricities—has been repeatedly identified as a major factor contributing to structural vulnerability during earthquakes. In India, where several regions fall under Seismic Zones III, IV, and V as per IS 1893:2016 (Part 1), the consequences of such irregularities can be severe if not addressed in the design stage. Irregular plan layouts alter the stiffness and mass distribution, often creating a mismatch between the centre of mass (CM) and centre of rigidity (CR). This results in significant torsional effects, stress concentrations, and non-uniform displacement patterns. Post-earthquake damage surveys, such as those following the 2001 Bhuj earthquake, have shown that irregular buildings suffered disproportionate damage compared to their regular counterparts. The current study aims to evaluate the seismic response of horizontally irregular RC buildings in compliance with Indian Standards, using analytical modelling and performance assessment techniques. By comparing regular and irregular configurations, the research seeks to provide practical recommendations for achieving torsional stability and improved seismic resilience. Civil Engineering Horizontal geometric irregularity RC structures torsional irregularity reentrant corners diaphragm discontinuity seismic performance IS 1893:2016 centre of mass centre of rigidity torsional stability performance-based design Indian seismic zones Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 1. INTRODUCTION 1.1 Background of the Project 1.1.1 Horizontal Regularity In the Indian Standard IS 1893 (Part 1): 2016 , horizontal regularity refers to the uniformity and balance of a building in plan. It is about ensuring that the shape, weight, and stiffness of the structure are arranged evenly in the horizontal direction so that, during an earthquake, the forces are transferred smoothly without causing twisting (torsion) or overstressing certain parts of the building. A building is said to have horizontal regularity when · Its plan shape is simple and free from large projections or deep reentrant corners. · The mass (weight of each floor) and stiffness (resistance to movement) were distributed symmetrically about both main axes. The center of mass and center of rigidity are close to each other; therefore, the building does not twist significantly during shaking. As per IS 1893:2016 Clause 7.1 and Table 4, The code lists certain plan irregularities that break the horizontal regularity. 1.1.1 Re-entrant corners – Shapes such as L, Z, T, U, or cross plans, where corners create stress concentrations. If projections are more than 15% of the building dimension in that direction, they are considered irregular. 1.1.2 Torsional irregularity – When the maximum lateral displacement (storey drift) at one edge of a floor is more than 1.5 times the average drift of that floor. 1.1.3 Non-parallel systems – When frames, shear walls, or bracing systems are not parallel to the main building axes. 1.1.4 Diaphragm discontinuity – Large openings in the floor slab (such as atriums or staircases) that reduce its stiffness. 1.1.5 Out-of-plane offsets – Sudden changes in the alignment of columns or walls from one floor to another. 1.2 Why Horizontal Irregularity is a Concern 1. This causes torsional effects and uneven force distribution. 2. This increases the chances of localized failure . 3. It reduces seismic performance and may require special analysis (e.g., 3D dynamic analysis). 4. Buildings with significant horizontal irregularities cannot use simplified seismic analysis methods in IS 1893; they must undergo detailed analysis. 1.3 Design Philosophy for Irregular Structures The design approach for horizontally irregular buildings follows two main principles. 1.3.1 Minimization of irregularity at the planning stage to simplify load transfer and reduce torsional effects is required. 1.3.2 Enhanced analysis, design, and detailing measures are required when irregularities are unavoidable. IS 1893 mandates that buildings with significant plan irregularities be analyzed using dynamic methods (Response Spectrum Analysis or Time History Analysis), ensuring accurate modelling of eccentricities and stiffness distribution. 1.4 Measures to Overcome Horizontal Irregularity Horizontal irregularity can be mitigated through a combination of architectural modifications , structural system adjustments , and analysis-based design enhancements . 1.4.1 Architectural Modifications 1) Simplify the plan geometry to avoid large re-entrant corners and projections. 2) Limit projections to less than 15% of the plan dimensions in the respective direction. 3) Relocate heavy rooftop or floor-level equipment towards the center of mass to minimize eccentricity. 4) The columns, shear walls, and frames are aligned vertically to maintain continuity in the load paths. 1.4.2 Structural System Adjustments 1.4.2.1 Addition of Shear Walls – Strategically place shear walls to bring the center of rigidity closer to the center of mass. 1.4.2.2 Use of Braced Frames : Steel bracing is provided in bays to improve the lateral stiffness distribution. 1.4.2.3 Coupling of Walls – Coupling beams are used to interconnect adjacent wall segments for better stiffness sharing. 1.4.2.4 Strengthened Diaphragms – Introduce collector beams and diaphragm stiffening to ensure efficient in-plane load transfer. 1.4.2.5 Mass Redistribution – Relocating heavy components to reduce eccentricity. 1.5 Structural Wall System A shear wall is a vertical structural element designed to resist lateral loads , such as those from wind and earthquakes, acting in the plane of the wall. Shear walls provide stiffness and strength to buildings, limiting lateral sway and preventing excessive deformation during seismic events. In earthquake-prone areas, such as Seismic Zones IV and V of India, the incorporation of shear walls is an essential design strategy to enhance the performance of multi-storey reinforced concrete (RC) buildings. The Indian Standards , particularly IS 456:2000 (Plain Reinforced Concrete – Code of Practice) and IS 13920:2016 (Ductile Detailing of RC Structures Subjected to Seismic Forces), provide specific guidelines for the design, and detailing, and ductility requirements of shear walls. 1.5.1 Importance of Shear Wall in Structural System Shear walls function as lateral force-resisting systems , carrying horizontal shear forces to the foundation while reducing bending moments in the beams and columns. Their advantages include the following: 1. Increased Lateral Stiffness – Reducing inter-storey drift. 2. Higher Strength – Allowing buildings to withstand larger lateral loads. 3. Efficient Load Transfer – Directly transferring forces to the foundation. 4. Reduced Damage to Non-Structural Elements : Protecting infill walls and finishes during earthquakes. 1.5.2 Codal Provisions for Shear Walls 1.5.2.1 IS 456:2000 1. The shear walls were designed as vertical cantilevers fixed at the base. 2. They must resist combined axial loads and bending owing to lateral forces. 3. The design must consider the minimum reinforcement provisions: a. Vertical reinforcement: Not less than 0.25% (HYSD bars) of the cross- sectional area. b. Horizontal reinforcement: Not less than 0.25% (HYSD bars) of the cross- sectional area of the member. 4. The maximum spacing of the reinforcement is three times the wall thickness or 450 mm , whichever is less. 1.5.2.2 IS 13920:2016 (Ductile Detailing) For buildings in Seismic Zones III, IV, and V : 1. Minimum thickness of RC shear wall: 150 mm (for low-rise) and typically 200–300 mm (for high-rise structures). 2. Boundary elements must be provided at the edges of the walls, where high compressive stresses develop. 3. Coupling beams between shear walls must be designed with diagonal reinforcement if their span-to-depth ratio is less than 2.0 m. 4. Lap splices of vertical reinforcement must be located away from the potential plastic hinge regions. 1.5.2.3 IS 1893 (Part 1): 2016 (Seismic Loads) 1. Shear walls are classified as Special RC Shear Walls when designed with ductile detailing per IS 13920. 2. They are modeled as vertical cantilever elements in structural analysis. 1.6 Aim The aim of this dissertation is to study the effect of seismic forces on RC high rise buildings in seismic zone V with horizontal irregularity for high rise RC building structure. 1.7 Objective The objectives adopted to study the effect of seismic forces on RC High Rise Structure is as follows: i) To incorporate Horizontal Geometric Irregularity in symmetrical and unsymmetrical building structure ii) To perform linear dynamic analysis (Response Spectrum Method). iii) To analyse and investigate the behaviour of the structure subjected to vertical geometric irregularity iv) To interpret the seismic responses (storey displacement, storey drift and storey stiffness) and suggest effective measures to mitigate geometric irregularity. 1.8 Scope of Study This study investigates the impact of horizontal geometric irregularities on reinforced concrete (RC) high-rise structures located in Seismic Zone V . Horizontal geometric irregularities refer to plan-wise asymmetries in a building’s configuration, such as L-, T-, or U-shaped plans, re-entrant corners, setbacks in plan, or unequal stiffness/mass distribution across the horizontal plane. These irregularities can significantly influence the seismic behavior of buildings by inducing torsional effects, uneven load transfer, and localized stress concentrations, thereby increasing the risk of damage during strong earthquakes. The primary objective of this study is to analyze how horizontal geometric irregularities affect the behavior and seismic performance of RC high-rise buildings, with a focus on identifying associated risks and proposing effective mitigation strategies to enhance safety and resilience. This study will utilize a combination of analytical, numerical, and case study methods: 1. Analytical Methods: An exhaustive literature review of pertinent structural design codes and guidelines (e.g., IS 1893:2016 and IS 13920:2016) pertaining to horizontal irregularities. 2. Numerical Simulations: Finite Element Analysis (FEA) will be utilized to simulate different forms of plan irregularities and analyze their effect on parameters such as base shear distribution, lateral displacement, torsion, and inter-storey drift. 3. Case Studies: Study of current high-rise buildings with reported horizontal irregularities to study actual performance and cross-check simulation outcomes. The study will concentrate on major structural performance factors such as: a) Seismic response and torsional behavior due to irregular plan geometry. b) Load distribution patterns and stress concentrations within structural members. c) Weak spots and potential failure modes due to irregular layouts. The findings will be contrasted against theoretical estimates and current code provisions, with comment on their import for practice. Possible mitigation strategies, e.g., optimal scheduling of shear walls, dual systems, and symmetrical stiffness distribution, will be investigated to reduce detrimental consequences. The research intends to deliver a comprehensive and applicable insight into the way horizontal geometric irregularities affect the seismic performance of RC high-rise buildings. The results will aid in developing better design practices and code provisions, leading to safer, more resilient building structures in earthquake-active regions. Research recommendations will cover new structural configurations and new materials in irregular plan designs.. 1.9 Need for Research Seismic Zone V ranks as a zone of very high seismic activity, where the probability of frequent and strong earthquakes is high. Structures placed within this zone are at a large risk of struggling with stability and safety, particularly when they have horizontal geometric irregularities. These irregularities take place when the plan shape of the structure is asymmetrical, re-entrant (L-, T-, or U-shaped), or has major in mass, stiffness, or load distribution in the direction of the horizontal plane. Such aberrations can lead to torsional effects, non-uniform load transfer, and localized stress concentrations, increasing the structure towards seismic damage. The general purpose of this study is to determine and assess structural systems and design approaches which can adequately counteract the extra stresses and dynamic The primary objective of this research is to identify and evaluate structural systems and design strategies that can effectively address the additional stresses and dynamic complexities introduced by horizontal irregularities in high-rise reinforced concrete buildings located in Seismic Zone V . The research focuses on developing approaches that enhance earthquake resistance while complying with relevant Indian Standards (IS) . This involves: 1. Assessing Structural Behavior: Investigation into how different structural systems and configurations react to seismic forces under the influence of horizontal irregularities, such as the influence of torsion, differential displacement, and in-plane stress distribution. 2. Design Optimization: Exploring design approaches—such as symmetrical stiffness distribution, select placement of shear walls, and torsional balancing—that can reduce the negative effect of plan irregularity and allow for more equitable seismic force distribution. 3. Safety Enhancement: Maintaining safety and functionality of horizontally irregular buildings during and after intense earthquakes through enhancement of redundancy, ductility, and overall structural resilience, thus decreasing the chances of partial or total collapse. 4. Code Compliance: Suggesting strengthening existing building codes (e.g., IS 1893:2016 and IS 13920:2016) to improve seismic design aspects of horizontally irregular buildings in high seismic areas. In the end, this study seeks to enhance the performance of horizontally irregular high-rise structures in Seismic Zone V, so that they are resilient to extreme seismic events without substantial structural or functional impairment. By combining analytical, numerical, and experimental methods, the study will contribute valuable insights for both practicing engineers and code development committees, helping to reduce earthquake- related risks and improve building safety in vulnerable regions. 2. LITERATURE REVIEW 2.1 INTRODUCTION This chapter includes review of various research papers on the effect of irregularities on various building systems individually. An introduction about the effect of different structural systems in various seismic zones is reviewed with the most significant investigations reported in the literature also included. 2.2 REVIEW OF PREVIOUS STUDIES Dileshwar Rana et al. [1] studied on ―Seismic Analysis of Regular & Vertical Geometric Irregular RCC Framed Building‖. Researchers compared the shear force, a measure of earthquake force, across different building designs. They analyzed each floor individually and compared buildings of the same height but varying shapes. Buildings with setbacks (protruding sections) experienced higher shear forces than regular buildings. This effect became more significant with increasing setbacks. The study also investigated the bending moment, the twisting force buildings experience during earthquakes. Irregular buildings, including those with setbacks, faced higher bending moments than regular ones, regardless of height. This is due to the reduced stiffness of irregular structures, making them more susceptible to twisting. As a result, irregular buildings require more reinforcement to withstand these greater forces. Response spectrum analysis (RSA) was used to compare the earthquake response of irregular buildings to a regular one. Ravindra N. Shelke et al. [2] examined the seismic demand (forces the structure needs to withstand) increases with higher seismic zones, requiring stronger buildings. Response spectrum method is recommended for high-rise or irregular buildings as it provides a more realistic assessment compared to simpler methods. Arup et al. [3] carried out the research on ―Simplified analysis method found effective for base- isolated buildings, including irregular ones‖. The study found that the simplified static analysis with a specific force distribution based on the first eigen mode provided results very close to the more complex response spectrum analysis, even for irregular buildings. This applies to both stiff and flexible base isolation systems. While the simplified method might slightly underestimate the forces on the top floors of tall buildings, it generally provides more accurate results compared to another simplified method (linear distribution) which tends to overestimate top floor forces. ―Effects of vertical irregularities on the seismic behaviour of multi-storey buildings with base isolation‖ was researched by N.I. Doudoumis et al. [4] where a comparison of simplified static analysis using a specific force distribution based on the building's first vibration mode with a more complex multi-modal response spectrum analysis. The results showed that the simplified method provided very close results to the complex method for both regular and irregular base-isolated buildings, regardless of the base isolation system's stiffness. However, the simplified method might slightly underestimate forces on the top floors of tall buildings. This underestimation depends on the building's inherent damping and the effectiveness of the base isolation system in damping vibrations. He first eigen ode distribution is more accurate, especially for avoiding overestimation of forces on top floors. The study suggests that the simplified static analysis using the first eigen mode force distribution can be reliably applied to determine the seismic response of both regular and irregular base-isolated buildings. Omkar M. Todkar et al. [5] investigated on ―Study of Seismic Response of Multi-Storied Vertical Irregular Building Due to Stiffness Irregularity‖. Study finds irregular buildings with sudden height changes move more under lateral loads. Uniform stiffness and regular shapes are ideal for better performance. Top floor irregularity may be slightly less harmful than lower ones, but avoiding irregularities is best. In the Comparison of Analysis and Design of Regular and Irregular Configuration of Multi Story Building in Seismic Zones various parameter such as story shear force, mass irregularity, time history analysis, stiffness irregularity and vertical geometric irregularity. Were researched. In conclusion, El Sayed Abdel Naby et al. [6] stated the shear force is highest in the first floor, decreasing towards the top, regardless of irregularity type. There is increase in base shear compared to regular buildings in mass irregularity. Stiffness irregularity also Reduces base shear but increases inter-story drifts. Geometry irregularity leads to higher displacements in upper stories compared to regular buildings, converging towards the lower stories. R Ismail et al [7] studied ―Seismic performance for vertical geometric irregularity frame structures‖. This study investigated the stress and displacement of buildings with vertical geometric irregularities (uneven shapes) subjected to seismic forces (earthquakes). The analysis considered both the normal building load and the seismic wave to understand the combined effect. Using eigenvalue analysis, the study identified the locations of maximum stress (critical points) under seismic loading. The overall results suggest that the vertical geometric irregularity frame can withstand the variations in loading and forces due to the earthquake. Additionally, the analysis of mode shapes revealed that the frame experiences swaying movements but the displacements are not significant. In conclusion, the study suggests that the vertical geometric irregularity in this specific case seems to be safe under the applied seismic performance loading. ―Irregularity effects on the seismic performance of l-shaped multi-story buildings‖ was examined by Momen M. M. Ahmed et al [8]. When a floor is not stiff enough (like an L-shape), the distribution of earthquake forces and the building's response are significantly affected. Consequences of neglecting irregularity: Local damage: Uneven force distribution can cause torsion and damage to outer columns, jeopardizing the building's stability during earthquakes. Designing without considering irregularity can lead to miscalculations in the building's seismic performance. Impact on functionality: Irregularity can lead to increased lateral deflections (swaying) and inter- story drifts (movement between floors), compromising the building's functionality and potentially leading to performance failures. Mohd. Swaliheen et al. [9] researched ―Seismic Response of Vertically Irregular RC Frame with Stiffness Irregularity at Fourth Floor‖. Frame 1: Vertically irregular (uneven floor heights). Frame 2: Stiffness irregularity on a vertically irregular frame (combination of uneven floor heights and stiffness variations). Frame 2 (combined irregularity) performed worse than Frame 1 (only vertical irregularity) under lateral loads (earthquakes): Larger story displacements: Frame 2 experienced significant changes in displacement across all floors, indicating greater movement and potential structural weakness. Higher story drifts: Frame 2 showed extreme changes in story drift (movement between floors) at the level with the increased height, suggesting higher stress concentration and potential damage. Slightly higher story shear: Frame 2 experienced slightly higher forces at each floor level compared to Frame 1. Pravin S Patil et al. [10] studied “ RCC Structure with Different Bracing Configuration on Seismic Issues‖. This study compared different types of bracing (like X, V, and eccentric) in two building models. They found that all bracing configurations can help control the building's behavior under different loads, including earthquakes. X-bracing was the most effective, reducing forces, bending, and vibration time. Inverted V and Eccentric Backward were also good options. Overall, X-bracing was the best at controlling horizontal movement. These findings suggest that bracing can be a valuable tool for designing tall buildings in the future. ―Analysis & design of G+20 RCC building using X-bracing system with base Isolator‖ was studied by Ashish R. Kondekar et al. [11] using X-bracing can help prevent buildings from collapsing and reduce the forces on the building during an earthquake. This makes the building more stable. However, it can also increase the displacement of each floor. Overall, X-bracing can improve a building's earthquake resistance and potentially reduce the amount of reinforcing steel needed. Rohan Chavan et al . [12] studied ―Seismic Analysis of Irregular RC Structure with Cross-Bracing System‖. This study analyzed the effectiveness of steel bracing in improving the earthquake resistance of a 11-story building. The results showed that adding steel bracing, even with a minimal increase in weight, significantly reduces lateral movement, bending forces, and story drift. This makes the building more stable during earthquakes. Both X-bracing and other types of bracing were found to be effective in improving structural performance. These findings suggest that steel bracing can be a valuable tool in designing earthquake-resistant buildings. 2.3 CRITICAL APPRAISAL OF LITERATURE The reviewed studies collectively highlight several critical points regarding the impact of vertical geometric irregularities on the seismic performance of RC high-rise buildings. Irregular buildings, particularly those with setbacks or uneven floor heights, experience higher shear forces and bending moments due to reduced stiffness, necessitating additional reinforcement. The response spectrum analysis method is recommended for more accurate assessment of seismic response in irregular and high-rise buildings. Simplified static analysis methods, especially those using the first eigen mode force distribution, can provide reliable results similar to more complex methods, although they may slightly underestimate forces at the top floors. Abrupt changes in height and stiffness irregularities cause larger lateral displacements and story drifts, which can undermine structural integrity. Vertical geometric irregularities cause higher upper-story displacements, more base shear in the presence of mass irregularity, and certain stress concentrations due to seismic loading. Successful seismic design should control these irregularities to avoid local damage to provide uniform distribution of forces, and ensure the functioning of buildings before, during, and after earthquakes. In total, these results highlight the importance of strong design measures and precise seismic analysis to promote the longevity and safety of irregular RC high-rise buildings in seismically active regions. 3. METHODOLOGY 3.1 INTRODUCTION This chapter provides an overview of the different methods used for the analysis of building systems. Furthermore, it delves into the complexities of structural analysis software ETABS, offering detailed information on the modeling processes, loading as well as analysis and within this particular software. 3.2 Response Spectrum Analysis Response Spectrum Analysis (RSA) is a most widely accepted and code recommended practices for seismic assessment of structures, particularly in situations where irregularities in mass distribution or geometry render the dynamic behavior complicated. For horizontally irregular structures, the response to earthquakes is extremely sensitive to torsional behaviors, eccentricity of mass, and stiffness variation over the plan.. In RSA, the structure is modeled as a multi-degree-of-freedom (MDOF) system, which is then decomposed into a series of single-degree-of-freedom (SDOF) modal shapes through eigenvalue analysis. Each mode is subjected to the design response spectrum as per IS 1893 (Part 1): 2016 , considering the spectral accelerations corresponding to the natural time periods. For horizontally irregular structures, torsional modes are given special attention, and accidental eccentricity (minimum 5% of building dimension perpendicular to the direction of loading) is included to account for unforeseen asymmetries. The output of RSA includes modal displacements, storey shears, storey drifts, and base shear values, which are combined using modal combination rules such as Square Root of the Sum of Squares (SRSS) or Complete Quadratic Combination (CQC) , as recommended by the code for closely spaced modes. This approach ensures that irregularities in plan shape, stiffness distribution, and mass eccentricity are properly captured, leading to a more reliable seismic design. The key benefit of applying RSA to horizontally irregular structures is that it can calculate torsional amplification and determine the most important modes that affect the design. This facilitates focused strengthening interventions, for example, enhancing flexible wings of L-shaped or T-shaped plans' stiffness, redistributing mass to lower eccentricity, or adding supplemental damping devices. 3.3 Introduction to Etabs Software ETABS 22 (Extended Three-Dimensional Analysis of Building Systems) is an substantial improvement over previous releases, with more powerful tools for modeling, analyzing, and designing intricate building geometries, such as those with horizontal plan irregularities. Its enhanced finite element solver, torsional irregularity checks, and visualization capabilities make it especially well-suited to evaluate buildings that are not regular configurations. ETABS 22 enables engineers to develop an accurate three-dimensional representation of the irregular structure, including correct geometry, material properties, support conditions, and load paths. Make provisions for such irregularities as re-entrant corners, setbacks, wings, and non-uniform stiffness distribution can be represented exactly according to architectural plans, making certain that the dynamic behavior is properly modeled in the analysis.. When modeling a horizontally irregular building in ETABS 22, the process involves several additional considerations compared to a regular plan: 3.3.1 Grid and Geometry Definition The structural grid is created to reflect the irregular floor plan. For example, an L- shaped or T-shaped configuration is modeled directly, without artificially dividing it into multiple rectangles. This ensures accurate stiffness and torsional response calculation. 3.3.2 Material and Section Properties Concrete, steel, and composite material properties are defined as per IS 456:2000, IS 800:2007, or relevant codes. Section dimensions vary according to the plan shape to optimize stiffness distribution. 3.3.3 Diaphragm Assignment a) Rigid Diaphragm : Applied to floors with high in-plane stiffness (e.g., RC slabs without large openings). b) Semi-Rigid Diaphragm : Applied where the floor has significant flexibility or openings, enabling the software to capture in-plane distortion effects, which are especially important in irregular layouts. 3.3.4 Mass Source and Accidental Eccentricity Mass source includes dead load + appropriate live load portion as per IS 1893:2016. Accidental eccentricity is included either automatically through ETABS settings or manually by offsetting the center of mass. 3.3.5 Load Application and Combination Seismic loads are generated using IS 1893:2016 parameters, ensuring that plan irregularity effects are considered. Load combinations follow IS 456:2000 and IS 875 guidelines. 3.3.6 Meshing and Shell Element Assignment Slabs are modeled using shell elements with appropriate meshing to capture localized stress concentrations due to irregular geometry. 3.3.7 Membrane Elements for non-load bearing diaphragms. 3.3.8 Shell Elements for load-bearing slabs that contribute to stiffness. 3.3.9 Modal Analysis and RSA Execution Eigenvalue analysis is performed to identify natural periods and mode shapes, paying special attention to torsional modes. RSA is then executed using the design response spectrum. 3.3.10 Post-Processing and Code Checks Results are reviewed for storey drift limits, base shear distribution, and torsional irregularity ratios as per IS 1893:2016, Clause 7.1.2. Any exceedance prompts design modifications. 3.4 Analysis in ETABS 2018 Analysis in structural analysis software ETABS involves simulating and evaluating the behavior of a structure under various load conditions. ETABS employs advanced computational techniques to calculate structural responses such as displacements, forces, moments, and stresses. The analysis process in ETABS typically involves the following steps: i) Model Creation The structure is first modeled in ETABS, where the geometry, material properties, and support conditions are defined. This includes creating elements such as beams, columns, slabs, and walls, assigning appropriate cross-sectional properties and material properties. ii) Loading Different types of loads, such as dead loads, live loads, wind loads, seismic loads, and temperature loads, are applied to the structure. Loads can be applied directly to elements or through load patterns, which define the spatial distribution of loads on the structure. iii) Analysis Types ETABS offers various analysis types to evaluate the structural response. The most common analysis types include: a) Static Analysis T3.5his analysis calculates the structural response under steady loads, without considering the effect of time or dynamic factors. It is suitable for most normal load conditions and can provide information on member forces, displacements, and support reactions. b) Dynamic Analysis ETABS conducts modal analysis to find out the natural frequencies, mode shapes, and modal participation factors of the structure. Response spectrum analysis, time history analysis, or any other dynamic analysis technique can be used to compute the dynamic response.. c) Results and Post-processing After completion of analysis, ETABS yields comprehensive results including displacements, member forces, moments, shear forces, and other parameters. Results can be visualized using different graphs, contour plots and animations. Engineers are able to examine the structural integrity, determine the critical zones and take decisions based on the analysis results.. Overall, analysis in ETABS allows engineers to evaluate the structural behavior, assess the safety and performance of the design, and optimize the structure's design and detailing. It plays a crucial role in ensuring structural integrity, meeting design requirements, and enhancing the overall safety and efficiency of the structure. 3.5 Design parameters in ETABS Design in ETABS is the check on the structural elements of a building to ensure that they are in accordance with the necessary design standards and criteria. ETABS offers a full range of design tools that help engineers design structures which are safe, efficient, and conform to relevant design codes and laws. The process of design in ETABS generally includes the following steps: i. Code Selection Engineers define the design code or standard to be followed during the design process. ETABS accommodates several national and international design codes, including ACI (American Concrete Institute), AISC (American Institute of Steel Construction), Eurocode, and numerous others. The code chosen includes the criteria and requirements for structural design.Design Load Combinations ETABS automatically generates design load combinations based on the selected code and the defined load patterns. These combinations consider various load cases and load factors to simulate different load scenarios. Common load combinations include dead load, live load, wind load, seismic load, and temperature load. i. Design Checks ETABS performs a series of design checks on different structural elements to verify their strength, stability, and serviceability. These checks may include: a) Concrete Design ETABS checks the design of concrete elements such as beams, columns, slabs, and walls for factors such as flexural strength, shear capacity, and axial load resistance. b) Steel Design ETABS assesses the design of steel elements, including beams, columns, and braces, for factors such as strength, buckling resistance, and connection design. It verifies that the steel members comply with the specified code provisions. c) Seismic Design ETABS provides specialized seismic design capabilities to make sure that structures can withstand earthquake forces. It checks factors such as seismic base shear, inter-storey drift, and member ductility to ensure compliance with seismic design codes. d) Design Results After the design checks are performed, Engineers can review these results to assess the adequacy of the design and make necessary adjustments if needed. e) Design Optimization ETABS enables the engineers to iterate and optimize the design by modifying a number of parameters like member size, reinforcement detailing, and connection type. This iterative process assists in obtaining an optimized design that satisfies all necessary design criteria. With the use of ETABS design capabilities, the engineers can be assured that their structures are safe, cost-effective, and compliant with industry standards. ETABS simplifies the design process by it will automate much of the intricate computation and verification, enabling engineers to concentrate on key design choices and verify the structural integrity of the building. 4. MODELLING AND ANALYSIS 4.1 Introduction This section describes the modeling and analysis technique used to assess the seismic performance of the suggested horizontally irregular, symmetric and unsymmetric G+28 high-rise residential building designed with a Structural Wall System in Seismic Zone V. The analysis was conducted employing ETABS 2022, which is renowned for its powerful ability to model complicated building systems as per applicable IS codes. The structural system contains a centrally positioned reinforced concrete core, where vertical circulation elements like lift shafts and staircases are housed. To provide better lateral stiffness and restrict drift, shear walls are located at specified positions, forming an integrated structural system that can effectively resist seismic forces. The structural building was simulated using beam and column elements as frame members, whereas the slabs were specified as shell elements in order to simulate both in-plane and out-of-plane characteristics. Rigid diaphragm constraints were applied at every floor level in order to mimic the realistic collective displacement of the floor slabs under lateral loading.Design loads were defined based on IS 875 (Part 1, Part 2, and Part 3) for dead, live, and wind loads respectively, while seismic parameters were specified according to IS 1893 (Part 1): 2016 for Zone V with medium soil conditions. Load combinations were automatically generated in ETABS to ensure that all critical loading scenarios were accounted for as per codal provisions. To study the dynamic response, a modal analysis was first conducted to extract the fundamental natural periods and mode shapes of the building. This was followed by a Response Spectrum Analysis (RSA), which provides a practical means to estimate the peak structural response to seismic excitations without requiring a full time history record. The response spectrum was defined in accordance with IS 1893, considering a damping ratio of 5% for reinforced concrete structures. Key output parameters such as base shear, lateral displacements, inter-storey drift, and mode shapes were carefully reviewed. The results indicate that the core and outrigger system effectively enhances the lateral stiffness of the building and keeps storey drift within permissible limits. This confirms the suitability of the selected structural system for a high-rise building in a high seismic risk zone. 4.2 BUILDING PARAMETERS This study primarily focuses on the dynamic analysis of a high rise building structure by considering the seismic zone V for Shillong location on the North-East of India. The overall analysis is done for a Twenty-eight storey high rise building structure in ETABS software. Table: 4.1 Building Parameters Parameters Details Plan Area (mm 2 ) 21.5X116.3 Plinth Beam Size (mm) 300X450 Floor Beam Size (mm) 300X700 Shear Wall (mm) 300X1000 Slab Thickness (mm) 150 External Wall Thickness (mm) 300 Floor to Floor Height (mm) 3000 Height of Building (mm) 84000 Table 4.1 provides information about various aspects of a building, including the plan area, beam and column size, slab thickness, and height. 4.2 LOADING PARAMETERS Calculating loading parameters in structural analysis involves determining load types and magnitudes, combining them into load combinations, considering load distribution and application points, calculating load effects using structural mechanics principles, and comparing them to element capacities for stability and safety. Understanding load types and their effects is crucial, such as assuming concrete density as 25 kN/m³ and brick density as 18 kN/m³. 4.2.1 Seismic Load Parameters As per IS 1893 Part I 2016, the Indian standard code for earthquake loads on buildings and structures, earthquake load parameters are defined to ensure the structural safety and stability of buildings. The soil type considered for the analysis is Type II soil (Medium – stiff). The importance factor, response reduction factor, time period, design acceleration coefficient is given in the table 4.2 below: Table:4.2 Earthquake Load Details for Building Particulars Details City Shillong Seismic Zone V Importance Factor (I) 1.20 Response Reduction Factor (R) 5 Time Period (seconds) 2.069 Design Acceleration Coefficient (Ah) 0.036 4.3 LOAD COMBINATIONS In the limit state design of reinforced concrete structures, load combinations are determined based on the guidelines provided in IS Code 456 Table 18. These load combinations are essential for ensuring the safety and reliability of the structures. The table specifies the partial safety factors to be applied to different types of loads, such as dead load, live load, wind load, and earthquake load. By considering these load combinations, the various possible scenarios and design structures that can withstand the expected loads and forces are defined below: Table 4.3 Static Earthquake Load Combinations EQ LOAD COMBOS NAME 0.9DL + 1.5 EQPX D9EQPX15 0.9DL + 1.5 EQNX D9EQNX15 0.9DL + 1.5EQPY D9EQPY15 0.9DL + 1.5EQNY D9EQNY15 0.9DL – 1.5 EQPX D9EQPNX15 0.9DL – 1.5 EQNX D9EQNNX15 0.9DL –1.5EQPY D9EQPNY15 0.9DL – 1.5EQNY D9EQNNY15 1.2 (DL + LL + EQPX) EQPX12 1.2 (DL + LL + EQNX) EQNX12 1.2 (DL + LL + EQPY) EQPY12 1.2 (DL + LL + EQNY) EQNY12 1.2 (DL + LL – EQPX) EQPNX12 1.2 (DL + LL – EQNX) EQNNX12 1.2 (DL + LL – EQPY) EQPNY12 1.2 (DL + LL – EQNY) EQNNY12 1.5 (DL + EQPX) EQPX15 1.5 (DL + EQNX) EQNX15 1.5 (DL + EQPY) EQPY15 1.5 (DL + EQNY) EQNY15 1.5 (DL – EQPX) EQPNX15 1.5 (DL – EQNX) EQNNX15 1.5 (DL – EQPY) EQNNY15 1.5 (DL – EQNY) EQNNY15 Table 4.4 Dynamic Earthquake Load Combinations SPEC LOAD COMBOS NAME 0.9DL + 1.5SPECX D9SPECX15 0.9DL + 1.5SPECY D9SPECY15 0.9DL – 1.5SPECX D9SPECNX15 0.9DL – 1.5SPECY D9SPECNY15 1.2 (DL+ LL + SPECX) SPECX12 1.2 (DL + LL + SPECY) SPECY12 1.2 (DL + LL – SPECX) SPECNX12 1.2 (DL + LL – SPECY) SPECNY12 1.5 (DL + SPECX) SPECX15 1.5 (DL + SPECY) SPECY15 1.5 (DL – SPECX) SPECNX15 1.5 (DL – SPECY) SPECNY15 Table 4.5 Serviceability Load Combinations EQ COMBO NAME DL+EQPX DEQPX DL+EQNX DEQNX DL+EQPY DEQPY DL+EQNY DEQNY DL-EQPX DEQPNX DL-EQNX DEQNNX DL-EQPY DEQPNY DL-EQNY DEQNNY DL+0.8(LL+EQPX) DLEQPX8 DL+0.8(LL+EQNX) DLEQNX8 DL+0.8(LL+EQPY) DLEQPY8 DL+0.8(LL+EQNY) DLEQNY8 DL+0.8(LL-EQPX) DLEQPNX8 DL+0.8(LL-EQNX) DLEQNNX8 DL+0.8(LL-EQPY) DLEQPNY8 DL+0.8(LL-EQNY) DLEQNNY8 4.4 STRUCTURAL SYSTEMS MODELING ETABS SOFTWARE In the ETABS software, two plans are designed including structural wall system. These structural systems are analyzed under various load combinations mentioned in the above tables. Table 4.6 provides detailed information about all three models, including their respective structural systems. This data helps in evaluating the performance and behavior of each model under the seismic conditions under different structural systems, allowing to study various parameters such as storey displacement, storey drift and storey stiffness. Table 4.6 Structural Systems Models in ETABS Model No. Type of Structural System Plan A Structural Wall System Plan B Structural Wall System The following figures reflect the comprehensive plan, 3D visualization, and loading analysis created with the ETABS software. From the figures, different architectural plan of structural wall system utilized in various models is shown. The comprehensive plan identifies the project goals, strategies, and activities in a systematic and thorough way. The 3Dvisualization provides the visual presentation of the structures such that better understanding of their overall shape and geometry. Moreover, the loading analysis gives an idea of how various loads, including gravity and wind forces influence the structural behavior of every model. In Figure 2(a) & 2(b), showcase the shear wall structural system employed in this particular model. The figure visually presents the layout and arrangement of the shear walls within the model, providing insights into the structural configuration. For the analysis, a consistent thickness of 300 mm is considered for the shear walls. The structure incorporates a central core and shear walls positioned along with some walls equally distributed on the both the axes. These shear walls, including the core of the structure, share the same type and dimensions, ensuring uniformity throughout the design. Figure 4.3 & 4.4 provides a visual representation of the Z shaped structure having structural wall system utilized in Model II. The figure showcases the arrangement and configuration of the horizontally irregular structure whose ratio of re-entrant corner is greater that 1.5(IS 1893-2016, Cl- no.7.1, Pg-no.15). A central reinforced concrete or composite core is employed as the primary vertical and lateral load-resisting element. This core accommodates essential building services such as lift shafts, stairwells, and utility ducts, making it a functionally integrated component of the building design. 5. RESULTS AND DISCUSSION 5.1 INTRODUCTION The results chapter is not only a presentation of numbers, but also a reflection of how the structural system responds to different design choices. In this study, ETABS models were created for the same building, with the only variation being the position of the shear walls. The intention was to understand how changing the location of shear walls influences the seismic performance of the structure in terms of displacement, drift, and base shear. Shear walls are known to provide stiffness and strength to RC buildings, but their effectiveness greatly depends on their placement. A centrally located wall may improve symmetry, whereas walls at the periphery can increase lateral stiffness. Conversely, poorly placed or asymmetrically distributed walls may lead to torsional irregularities and undesirable response. Therefore, by modeling different configurations, the analysis aims to highlight not just which option performs best, but also why that configuration is superior. In this study, the same building was analyzed with different shear wall layouts. The results are compared in terms of roof displacement, inter-storey drift, and base shear. The following sections explain, step by step, how the analysis was carried out in ETABS, what results were obtained at each stage, and finally which model performed the best. This makes it clear how the final values were reached and why certain shear wall positions are more effective than others. Modal Participating Mass Ratios Table: 5.1- Mode Shapes Structural Wall System Mode Period (sec) UX UY RZ Plan A (1) 1 7.8 0% 24% 50% 2 5.3 %0 50% 24% 3 4.01 %83 0% 0% Plan A (2) 1 5.10 0% 0% 73% 2 5.15 0% 72% 5% 3 0.1 83% 0% 0% Plan A (3) 1 4.27 0% 18% 75% 2 4.18 0% 74% 15% 3 2.53 83% 0% 0% Plan A (4) 1 4.92 0% 6% 63% 2 4.68 0% 63% 6% 3 3.45 76% 0% 0% Storey Displacement Displacement due to Seismic Load Table:5.2- Storey Dispalcement due to Seismic Load Structural WallSystem Maximum Displacement Displacement in X direction Displacement in Y direction Plan A 333.6 160.3 370.15 Plan B 333.6 231.02 420.36 333.6 150.25 350.37 333.6 148.01 325.3 Displacement due to wind Load Table:5.3- Displacement due to Wind Load Structural WallSystem Maximum Displacement Displacement in X direction Displacement in Y direction Plan A (1) 166.8 120.7 330 Plan A (2) 166.8 70 400.2 Plan A (3) 166.8 105.01 370.37 Plan A (4) 166.8 35 338 5.2.3 Storey Drift Table:5.4- Storey Drift Structural Wall System Maximum Drift Drift in X direction Spec X Drift in Y direction Spec Y Plan A (1) 1.5 1.3 1.03 Plan A (2) 1.5 1.02 1.22 Plan A (3) 1.5 1.01 1.4 Plan A (4) 1.5 1.01 1.03 From the analysis of all four ETABS models, it is clear that the position of shear walls has a significant impact on the structural response. Among the different configurations, Plan A (4) shows the most favorable performance. The central placement of shear walls reduces overall roof displacement and keeps inter-storey drift within permissible limits. The mode shapes indicate a uniform distribution of stiffness, while torsional effects are minimal compared to the other layouts. Therefore, Plan A can be considered the most suitable arrangement, as it provides both structural efficiency and stability under seismic loading. 5.2 Time Period In structural analysis, time period is the time taken by a building to travel through one complete cycle of vibration when it is acted upon by lateral forces like those caused by earthquakes or cyclonic winds in cyclonic areas. It is a critical parameter in the structural design and analysis of buildings, as it determines the natural frequency of the building, which in turn determines its resistance to external forces. The time period depends on many factors, such as the building's height, weight, and stiffness, as well as the structural system employed in its construction. Through proper estimation of a building's time period, architects and engineers can plan structures that are safer and more resistant to external forces, minimizing the chances of damage or collapse during earthquakes. Practically, a larger time period means smaller natural frequency, which means that the building will vibrate more slowly in response to outside forces. On the other hand, less time duration indicates a greater natural frequency, and hence oscillations are faster. Engineers utilize the time duration quite heavily in structural dynamics in determining the response of the building to dynamic loads and designing suitable measures for seismic vibration risk mitigation. The time duration determined from different structural systems through analysis using the software is listed below in a tabular form. Modal Participating Mass Ratios Table: 5.2.1- Mode Shapes Structural Wall System Mode Period (sec) UX UY RZ Plan A 1 4.92 0% 6% 63% 2 4.68 0% 63% 6% 3 3.45 76% 0% 0% Plan B 1 3.99 63% 1% 1% 2 3.82 1% 71% 24% 3 2.43 0% 0% 41% The time period of the structural wall system is below 8 seconds is significant for several reasons as per IS 16700-2023, Clause 5.5.2, Page No 5. Firstly, it indicates that the structural system has a relatively high natural frequency, which means it can better resist lateral forces generated by earthquakes. This is because structures with higher natural frequencies are less likely to resonate with external forces and experience significant damage or collapse. 5.2.2 Storey Displacement Displacement due to Seismic Load Table: 5.2.2 Displacement due to Seismic Load Structural WallSystem Maximum Displacement Displacement in X direction Displacement in Y direction Plan A 333.6 148.01 325.3 Plan B 333.6 231 193 5.2.3 Displacement due to wind Load Table:5.2.3- Displacement due to Wind load Structural WallSystem Maximum Displacement Displacement in X direction Displacement in Y direction Plan A 166.8 35 338 Plan B 166.8 119 155 5.2.4 Storey Drift Table: 5.2.4- Storey Drift Structural Wall System Maximum Drift Drift in X direction Spec X Drift in Y direction Spec Y Plan A 1.5 1.01 1.03 Plan B 1.5 1 1 6. CONCLUSION 5.1 Conclusion The comparative dynamic performance analysis of Plan A (horizontal regular) and Plan B (horizontal irregular, unsymmetric) was conducted for a G+28 reinforced concrete structural wall system located in Seismic Zone V . Both configurations meet the IS 16700:2023, Clause 5.5.2 requirement of having a fundamental time period below 8 seconds, indicating higher natural frequencies that minimize resonance risks during seismic events. Modal Participating Mass Ratios · Plan B shows a strong concentration of modal mass participation in the primary modes, enabling efficient energy dissipation in both X and Y directions despite its asymmetry. · Plan A exhibits more evenly distributed mode shapes, beneficial for balanced seismic response. Storey Displacement · Under seismic loading, Plan B records lower displacement in the Y-direction (193 mm) compared to Plan A (325.3 mm), indicating improved lateral stiffness in that axis. · Under wind loading, Plan B again shows reduced displacement in the Y-direction (155 mm vs. 338 mm for Plan A), demonstrating better aerodynamic performance in one principal direction. Storey Drift · Both plans satisfy the drift limitations of IS 1893 (Part 1):2016 . · Plan B ’s drift distribution is slightly more localized but remains within permissible limits, suggesting potential for targeted strengthening rather than global modification. Overall Observation · Plan B achieves competitive or superior performance in the Y-direction for both seismic and wind loads, showing that well-designed irregular layouts can still perform effectively in high seismic zones. · Plan A maintains more predictable and balanced performance across both axes, making it inherently simpler to design for uniform lateral response. The study confirms that while Plan A offers a balanced and predictable response, Plan B demonstrates notable advantages in the Y-direction displacement and drift control under both seismic and wind loads. This shows that horizontal irregular structures , if carefully engineered, can achieve performance levels close to or even surpassing regular configurations in specific parameters, provided torsional effects are effectively managed. References [B] Journal Papers Xing, B., Lumantarna, E., Lam, N. T. K., & Menegon, S. (2021). Torsional rigidity of asymmetrical multi-storey reinforced concrete buildings. Australian Earthquake Engineering Society Journal , November. Swaliheen, M., & Bai, M. A. (2021). Comparison of analysis and design of regular and irregular configuration of multi story building in seismic zones. International Journal for Research in Applied Science & Engineering Technology , August. Botis, M. F., & Cerbu, C. (2020). A method for reducing of the overall torsion for reinforced concrete multi-storey irregular structures. Applied Sciences , August. https://doi.org/10.3390/appXXXX Todkar, O. M., & Salunke, P. J. (2019). Study of seismic response of multi-storied vertical irregular building due to stiffness irregularity. International Journal of Research in Engineering, Science and Management , January. Ismail, R., Mahmud, N. A., & Ishak, I. S. (2018). Seismic performance for vertical geometric irregularity frame structures. IOP Conference Series: Earth and Environmental Science , 140(1), 012128. https://doi.org/10.1088/1755- 1315/140/1/012128 Shelke, R. N., & Ansari, U. S. (2017). Seismic analysis of vertically irregular RCC building frames. International Journal of Civil Engineering and Technology , January. Ahmed, M. M. M., Abdel Raheem, S. E., Ahmed, M. M., & Abdel-Shafy, A. G. A. (2016). Irregularity effects on the seismic performance of L-shaped multi-story buildings. Journal of Engineering Sciences , September. Abdel Naby, E. S., & Abou Khalifa, N. A. A. (2015). Comparison of analysis and design of regular and irregular configuration of multi story building in seismic zones. Journal of Civil Engineering, United Arab Emirates University . Rana, D., & Raheem, J. (2015). Seismic analysis of regular & vertical geometric irregular RCC framed building. International Research Journal of Engineering and Technology (IRJET) , July. Monish, S., & Karuna, S. (2015). A study on seismic performance of high rise irregular RC framed buildings. International Journal of Research in Engineering and Technology , May. Shaikh, A., & Deshmukh, G. (2013). Seismic response of vertical irregular RCC frame with irregularity at 4th floor. International Journal of Emerging Technology and Advanced Engineering , August. Doudoumis, N. I., & Gravalas, F. (2005). Effects of vertical irregularities on the seismic behaviour of multi-storey buildings with base isolation. Research Gate , January. [C] Conference Papers Patil, P. S., & Sonar, I. (2018, March). RCC structure with different bracing configuration on seismic issues. In Proceedings of the Civil Engineering Conference , ResearchGate. Kondekar, A. R., Dolare, D. B., Balande, P. V., Shinde, D. S., & Alkunte, A. J. (2022, May). Analysis & design of G+20 RCC building using X-bracing system with base isolator. International Journal of Creative Research Thoughts . Chavan, R., & Sohoni, P. (2018). Seismic analysis of irregular RC structure with cross- bracing system. IJSRSET Conference Proceedings . [G] Standards & Codes Bureau of Indian Standards. (1987). IS 875 (Part 2): Code of practice for design loads (other than earthquake) for buildings and structures – Part 2: Imposed loads . New Delhi: BIS. Bureau of Indian Standards. (2000). IS 456: Code of practice for plain and reinforced concrete . New Delhi: BIS. Bureau of Indian Standards. (2016). IS 1893 (Part 1): Criteria for earthquake resistant design of structures . New Delhi: BIS Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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B\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"4.3.png","url":"https://assets-eu.researchsquare.com/files/rs-7438879/v1/b23a238446921065f7c7bc41.png"},{"id":89905524,"identity":"3a5832db-da2d-48a3-be7b-85e9f2a0fd2b","added_by":"auto","created_at":"2025-08-26 10:03:03","extension":"png","order_by":14,"title":"Figure 14","display":"","copyAsset":false,"role":"figure","size":48904,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFig: 4.4- Plan view of Plan B\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"4.4.png","url":"https://assets-eu.researchsquare.com/files/rs-7438879/v1/905ef3713a009f6eb75301c9.png"},{"id":89905523,"identity":"9a400811-d885-4a31-943e-882b482eecb3","added_by":"auto","created_at":"2025-08-26 10:03:03","extension":"png","order_by":15,"title":"Figure 15","display":"","copyAsset":false,"role":"figure","size":108612,"visible":true,"origin":"","legend":"\u003cp\u003eFig:5.1-Plan A (1)\u003c/p\u003e","description":"","filename":"5.1.png","url":"https://assets-eu.researchsquare.com/files/rs-7438879/v1/e0560803d36477b695a8b006.png"},{"id":89905528,"identity":"657a1db5-38b1-4891-a25a-97c1516ce288","added_by":"auto","created_at":"2025-08-26 10:03:03","extension":"png","order_by":16,"title":"Figure 16","display":"","copyAsset":false,"role":"figure","size":98027,"visible":true,"origin":"","legend":"\u003cp\u003eFig: 5.2- Plan A (2)\u003c/p\u003e","description":"","filename":"5.2.png","url":"https://assets-eu.researchsquare.com/files/rs-7438879/v1/35700763f05c98abbae06c19.png"},{"id":89905536,"identity":"8d79b49f-e188-44ea-a3fe-4dee93a7f4ad","added_by":"auto","created_at":"2025-08-26 10:03:03","extension":"png","order_by":17,"title":"Figure 17","display":"","copyAsset":false,"role":"figure","size":124758,"visible":true,"origin":"","legend":"\u003cp\u003eFig:5.3- Plan A (3)\u003c/p\u003e","description":"","filename":"5.3.png","url":"https://assets-eu.researchsquare.com/files/rs-7438879/v1/a0ee1b1aab1e1e211bd876f4.png"},{"id":89905529,"identity":"1ee4f584-da5a-4d4f-9426-1770128948ba","added_by":"auto","created_at":"2025-08-26 10:03:03","extension":"png","order_by":18,"title":"Figure 18","display":"","copyAsset":false,"role":"figure","size":107037,"visible":true,"origin":"","legend":"\u003cp\u003eFig:5.4- Plan A (4)\u003c/p\u003e","description":"","filename":"5.4.png","url":"https://assets-eu.researchsquare.com/files/rs-7438879/v1/d13d427cb45bbe395b3557cc.png"},{"id":89909063,"identity":"c27c23fb-cea7-43f2-af4e-81320dfec998","added_by":"auto","created_at":"2025-08-26 10:35:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3686437,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7438879/v1/67dc9279-ef39-42d8-b289-1eb9c109cc26.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003eEffect of Horizontal Geometric Irregularity on a High Rise RC Structure\u003c/p\u003e","fulltext":[{"header":"1. INTRODUCTION","content":"\u003ch3\u003e1.1 Background of the Project\u003c/h3\u003e\n\u003cp\u003e\u003cstrong\u003e1.1.1\u0026nbsp;\u003c/strong\u003eHorizontal Regularity\u003c/p\u003e\n\u003cp\u003eIn the \u003cstrong\u003eIndian Standard IS 1893 (Part 1): 2016\u003c/strong\u003e, \u003cem\u003ehorizontal regularity\u0026nbsp;\u003c/em\u003erefers to the uniformity and balance of a building in plan. It is about ensuring that the shape, weight, and stiffness of the structure are arranged evenly in the horizontal direction so that, during an earthquake, the forces are transferred smoothly without causing twisting (torsion) or overstressing certain parts of the building.\u003c/p\u003e\n\u003cp\u003eA building is said to have horizontal regularity when\u003c/p\u003e\n\u003cp\u003e\u0026middot; Its plan shape is simple and free from large projections or deep reentrant corners.\u003c/p\u003e\n\u003cp\u003e\u0026middot; The mass (weight of each floor) and stiffness (resistance to movement) were distributed symmetrically about both main axes.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;The center of mass and center of rigidity are close to each other; therefore, the building does not twist significantly during shaking.\u003c/p\u003e\n\u003ch4\u003eAs per IS 1893:2016 Clause 7.1 and Table 4,\u003c/h4\u003e\n\u003cp\u003e\u003cstrong\u003eThe\u0026nbsp;code\u0026nbsp;lists\u0026nbsp;certain\u0026nbsp;plan irregularities\u0026nbsp;that\u0026nbsp;break\u0026nbsp;the\u0026nbsp;horizontal regularity.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.1.1 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eRe-entrant corners\u0026nbsp;\u003c/strong\u003e\u0026ndash; Shapes such as L, Z, T, U, or cross plans, where corners create stress concentrations. If projections are more than 15% of the building dimension in that direction, they are considered irregular.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.1.2 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eTorsional irregularity\u0026nbsp;\u003c/strong\u003e\u0026ndash; When the maximum lateral displacement (storey drift) at one edge of a floor is more than 1.5 times the average drift of that floor.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.1.3 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eNon-parallel systems\u0026nbsp;\u003c/strong\u003e\u0026ndash; When frames, shear walls, or bracing systems are not parallel to the main building axes.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.1.4 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eDiaphragm discontinuity\u0026nbsp;\u003c/strong\u003e\u0026ndash; Large openings in the floor slab (such as atriums or staircases) that reduce its stiffness.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.1.5 \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eOut-of-plane offsets\u0026nbsp;\u003c/strong\u003e\u0026ndash; Sudden changes in the alignment of columns or walls from one floor to another.\u003c/p\u003e\n\u003ch4\u003e1.2\u0026nbsp;Why\u0026nbsp;Horizontal\u0026nbsp;Irregularity\u0026nbsp;is\u0026nbsp;a Concern\u003c/h4\u003e\n\u003cp\u003e1.\u0026nbsp; \u0026nbsp;This\u0026nbsp;causes \u003cstrong\u003etorsional effects\u0026nbsp;\u003c/strong\u003eand uneven\u0026nbsp;force distribution.\u003c/p\u003e\n\u003cp\u003e2.\u0026nbsp; \u0026nbsp;This\u0026nbsp;increases\u0026nbsp;the chances\u0026nbsp;of \u003cstrong\u003elocalized failure\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003e3. \u0026nbsp; It reduces seismic performance and may require \u003cstrong\u003especial analysis\u0026nbsp;\u003c/strong\u003e(e.g.,\u0026nbsp;3D\u0026nbsp;dynamic analysis).\u003c/p\u003e\n\u003cp\u003e4. \u0026nbsp; Buildings with significant horizontal irregularities \u003cstrong\u003ecannot\u0026nbsp;\u003c/strong\u003euse simplified seismic analysis methods in IS 1893; they must undergo detailed analysis.\u003c/p\u003e\n\u003ch4\u003e1.3\u0026nbsp;Design\u0026nbsp;Philosophy\u0026nbsp;for\u0026nbsp;Irregular\u0026nbsp;Structures\u003c/h4\u003e\n\u003cp\u003eThe design approach for horizontally irregular buildings follows two main principles.\u003c/p\u003e\n\u003cp\u003e1.3.1 \u003cstrong\u003eMinimization of irregularity\u0026nbsp;\u003c/strong\u003eat the planning stage to simplify load transfer and reduce torsional effects is required.\u003c/p\u003e\n\u003cp\u003e1.3.2 \u003cstrong\u003eEnhanced analysis, design, and detailing measures\u0026nbsp;\u003c/strong\u003eare required when irregularities are unavoidable.\u003c/p\u003e\n\u003cp\u003eIS 1893 mandates that buildings with significant plan irregularities be analyzed using \u003cstrong\u003edynamic methods\u0026nbsp;\u003c/strong\u003e(Response Spectrum Analysis or Time History Analysis), ensuring accurate modelling of eccentricities and stiffness distribution.\u003c/p\u003e\n\u003ch4\u003e1.4\u0026nbsp;Measures\u0026nbsp;to\u0026nbsp;Overcome\u0026nbsp;Horizontal\u0026nbsp;Irregularity\u003c/h4\u003e\n\u003cp\u003eHorizontal irregularity can be mitigated through a combination of \u003cstrong\u003earchitectural modifications\u003c/strong\u003e, \u003cstrong\u003estructural system adjustments\u003c/strong\u003e, and \u003cstrong\u003eanalysis-based design enhancements\u003c/strong\u003e.\u003c/p\u003e\n\u003ch4\u003e1.4.1 \u0026nbsp; \u0026nbsp;Architectural Modifications\u003c/h4\u003e\n\u003cp\u003e1)\u0026nbsp; \u0026nbsp;Simplify\u0026nbsp;the plan\u0026nbsp;geometry\u0026nbsp;to\u0026nbsp;avoid\u0026nbsp;large\u0026nbsp;re-entrant\u0026nbsp;corners and projections.\u003c/p\u003e\n\u003cp\u003e2)\u0026nbsp; \u0026nbsp;Limit\u0026nbsp;projections\u0026nbsp;to\u0026nbsp;less than\u0026nbsp;15%\u0026nbsp;of the\u0026nbsp;plan\u0026nbsp;dimensions in\u0026nbsp;the\u0026nbsp;respective direction.\u003c/p\u003e\n\u003cp\u003e3)\u0026nbsp; \u0026nbsp;Relocate\u0026nbsp;heavy\u0026nbsp;rooftop\u0026nbsp;or\u0026nbsp;floor-level\u0026nbsp;equipment\u0026nbsp;towards\u0026nbsp;the\u0026nbsp;center\u0026nbsp;of\u0026nbsp;mass\u0026nbsp;to\u0026nbsp;minimize eccentricity.\u003c/p\u003e\n\u003cp\u003e4) \u0026nbsp; The columns, shear walls, and frames are aligned vertically to maintain continuity in the load paths.\u003c/p\u003e\n\u003ch4\u003e1.4.2\u0026nbsp; \u0026nbsp;\u0026nbsp;Structural\u0026nbsp;System\u0026nbsp;Adjustments\u003c/h4\u003e\n\u003cp\u003e\u003cstrong\u003e1.4.2.1\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eAddition of Shear Walls\u0026nbsp;\u003c/strong\u003e\u0026ndash; Strategically place shear walls to bring the center of rigidity closer to the center of mass.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.4.2.2\u0026nbsp;\u003c/strong\u003e\u0026nbsp; \u003cstrong\u003eUse of Braced Frames\u003c/strong\u003e: Steel bracing is provided in bays to improve the lateral stiffness distribution.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.4.2.3\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eCoupling of Walls\u0026nbsp;\u003c/strong\u003e\u0026ndash; Coupling beams are used to interconnect adjacent wall segments for better stiffness sharing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.4.2.4\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eStrengthened Diaphragms\u0026nbsp;\u003c/strong\u003e\u0026ndash; Introduce collector beams and diaphragm stiffening to ensure efficient in-plane load transfer.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.4.2.5\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eMass Redistribution\u0026nbsp;\u003c/strong\u003e\u0026ndash; Relocating heavy components to reduce eccentricity.\u003c/p\u003e\n\u003ch4\u003e1.5 \u0026nbsp; Structural Wall System\u003c/h4\u003e\n\u003cp\u003eA \u003cstrong\u003eshear wall\u0026nbsp;\u003c/strong\u003eis a vertical structural element designed to resist \u003cstrong\u003elateral\u0026nbsp;loads\u003c/strong\u003e, such as those from wind and earthquakes, acting in the plane of the wall. Shear walls provide \u003cstrong\u003estiffness\u0026nbsp;\u003c/strong\u003eand \u003cstrong\u003estrength\u0026nbsp;\u003c/strong\u003eto buildings, limiting lateral sway and preventing excessive deformation during seismic events.\u003c/p\u003e\n\u003cp\u003eIn earthquake-prone areas, such as \u003cstrong\u003eSeismic Zones IV and V\u0026nbsp;\u003c/strong\u003eof India, the incorporation of shear walls is an essential design strategy to enhance the performance of multi-storey reinforced concrete (RC) buildings. The \u003cstrong\u003eIndian Standards\u003c/strong\u003e, particularly \u003cstrong\u003eIS 456:2000\u0026nbsp;\u003c/strong\u003e(Plain Reinforced Concrete \u0026ndash; Code of Practice) and \u003cstrong\u003eIS 13920:2016\u0026nbsp;\u003c/strong\u003e(Ductile Detailing of RC Structures Subjected to Seismic Forces), provide specific guidelines for the design, and detailing, and ductility requirements of shear walls.\u003c/p\u003e\n\u003ch4\u003e1.5.1 \u0026nbsp; \u0026nbsp;Importance of Shear Wall in Structural System\u003c/h4\u003e\n\u003cp\u003eShear walls function as \u003cstrong\u003elateral force-resisting systems\u003c/strong\u003e, carrying horizontal shear forces to the foundation while reducing bending moments in the beams and columns. Their advantages include the following:\u003c/p\u003e\n\u003cp\u003e1. \u003cstrong\u003eIncreased Lateral Stiffness\u0026nbsp;\u003c/strong\u003e\u0026ndash; Reducing inter-storey drift.\u003c/p\u003e\n\u003cp\u003e2. \u003cstrong\u003eHigher\u0026nbsp;Strength\u0026nbsp;\u003c/strong\u003e\u0026ndash; Allowing buildings to withstand larger lateral loads.\u003c/p\u003e\n\u003cp\u003e3. \u003cstrong\u003eEfficient Load Transfer\u0026nbsp;\u003c/strong\u003e\u0026ndash; Directly transferring forces to the foundation.\u003c/p\u003e\n\u003cp\u003e4. \u003cstrong\u003eReduced\u0026nbsp;Damage\u0026nbsp;to\u0026nbsp;Non-Structural\u0026nbsp;Elements\u003c/strong\u003e: Protecting infill walls and finishes during earthquakes.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.5.2 \u0026nbsp; \u0026nbsp;Codal Provisions for Shear Walls\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.5.2.1\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eIS 456:2000\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e1.\u0026nbsp; \u0026nbsp;The\u0026nbsp;shear walls\u0026nbsp;were\u0026nbsp;designed\u0026nbsp;as \u003cstrong\u003evertical cantilevers\u0026nbsp;\u003c/strong\u003efixed\u0026nbsp;at\u0026nbsp;the base.\u003c/p\u003e\n\u003cp\u003e2.\u0026nbsp; \u0026nbsp;They\u0026nbsp;must\u0026nbsp;resist \u003cstrong\u003ecombined axial loads and bending\u0026nbsp;\u003c/strong\u003eowing\u0026nbsp;to\u0026nbsp;lateral forces.\u003c/p\u003e\n\u003cp\u003e3.\u0026nbsp; \u0026nbsp;The\u0026nbsp;design\u0026nbsp;must\u0026nbsp;consider\u0026nbsp;the \u003cstrong\u003eminimum reinforcement\u0026nbsp;\u003c/strong\u003eprovisions:\u003c/p\u003e\n\u003cp\u003ea. \u003cstrong\u003eVertical\u0026nbsp;reinforcement:\u0026nbsp;\u003c/strong\u003eNot less than 0.25% (HYSD bars) of the cross- sectional area.\u003c/p\u003e\n\u003cp\u003eb. \u003cstrong\u003eHorizontal\u0026nbsp;reinforcement:\u0026nbsp;\u003c/strong\u003eNot less than 0.25% (HYSD bars) of the cross- sectional area of the member.\u003c/p\u003e\n\u003cp\u003e4. \u0026nbsp; The maximum spacing of the reinforcement is \u003cstrong\u003ethree times the wall thickness\u0026nbsp;\u003c/strong\u003eor \u003cstrong\u003e450 mm\u003c/strong\u003e, whichever is less.\u003c/p\u003e\n\u003ch4\u003e1.5.2.2\u0026nbsp;IS\u0026nbsp;13920:2016\u0026nbsp;(Ductile Detailing)\u003c/h4\u003e\n\u003cp\u003eFor\u0026nbsp;buildings\u0026nbsp;in \u003cstrong\u003eSeismic Zones III, IV, and V\u003c/strong\u003e:\u003c/p\u003e\n\u003cp\u003e1. \u003cstrong\u003eMinimum\u0026nbsp;thickness\u0026nbsp;\u003c/strong\u003eof RC shear wall: \u003cstrong\u003e150 mm\u0026nbsp;\u003c/strong\u003e(for low-rise) and typically 200\u0026ndash;300 mm (for high-rise structures).\u003c/p\u003e\n\u003cp\u003e2. \u003cstrong\u003eBoundary\u0026nbsp;elements\u0026nbsp;\u003c/strong\u003emust be provided at the edges of the walls, where high compressive stresses develop.\u003c/p\u003e\n\u003cp\u003e3. \u003cstrong\u003eCoupling beams\u0026nbsp;\u003c/strong\u003ebetween shear walls must be designed with diagonal reinforcement if their span-to-depth ratio is less than 2.0 m.\u003c/p\u003e\n\u003cp\u003e4. \u003cstrong\u003eLap splices\u0026nbsp;\u003c/strong\u003eof vertical reinforcement must be located away from the potential plastic hinge regions.\u003c/p\u003e\n\u003ch4\u003e1.5.2.3 IS 1893 (Part 1): 2016 (Seismic Loads)\u003c/h4\u003e\n\u003cp\u003e\u003cstrong\u003e1. \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003eShear walls are classified as \u003cstrong\u003eSpecial RC Shear Walls\u0026nbsp;\u003c/strong\u003ewhen designed with ductile detailing per IS 13920.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2. \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003eThey are modeled as vertical cantilever elements in structural analysis.\u003c/p\u003e\n\u003ch4\u003e1.6 \u0026nbsp; Aim\u003c/h4\u003e\n\u003cp\u003eThe aim of this dissertation is to study the effect of seismic forces on RC high rise buildings in seismic zone V with horizontal irregularity for high rise RC building structure.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.7 Objective\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe\u0026nbsp;objectives\u0026nbsp;adopted\u0026nbsp;to\u0026nbsp;study\u0026nbsp;the\u0026nbsp;effect\u0026nbsp;of\u0026nbsp;seismic\u0026nbsp;forces\u0026nbsp;on\u0026nbsp;RC\u0026nbsp;High\u0026nbsp;Rise\u0026nbsp;Structure\u0026nbsp;is\u0026nbsp;as\u0026nbsp;follows:\u003c/p\u003e\n\u003cp\u003ei)\u0026nbsp;To\u0026nbsp;incorporate\u0026nbsp;Horizontal\u0026nbsp;Geometric\u0026nbsp;Irregularity\u0026nbsp;in\u0026nbsp;symmetrical\u0026nbsp;and\u0026nbsp;unsymmetrical building structure\u003c/p\u003e\n\u003cp\u003eii)\u0026nbsp;To\u0026nbsp;perform\u0026nbsp;linear\u0026nbsp;dynamic\u0026nbsp;analysis\u0026nbsp;(Response\u0026nbsp;Spectrum\u0026nbsp;Method).\u003c/p\u003e\n\u003cp\u003eiii)\u0026nbsp;To\u0026nbsp;analyse\u0026nbsp;and\u0026nbsp;investigate\u0026nbsp;the\u0026nbsp;behaviour\u0026nbsp;of\u0026nbsp;the\u0026nbsp;structure\u0026nbsp;subjected\u0026nbsp;to\u0026nbsp;vertical geometric irregularity\u003c/p\u003e\n\u003cp\u003eiv) To interpret the seismic responses (storey displacement, storey drift and storey stiffness) and suggest effective measures to mitigate geometric irregularity.\u003c/p\u003e\n\u003ch4\u003e1.8 \u0026nbsp; Scope of Study\u003c/h4\u003e\n\u003cp\u003eThis study investigates the impact of \u003cstrong\u003ehorizontal geometric irregularities\u0026nbsp;\u003c/strong\u003eon reinforced concrete (RC) high-rise structures located in \u003cstrong\u003eSeismic Zone V\u003c/strong\u003e. Horizontal geometric irregularities refer to plan-wise asymmetries in a building\u0026rsquo;s configuration, such as L-, T-, or U-shaped plans, re-entrant corners, setbacks in plan, or unequal stiffness/mass distribution across the horizontal plane. These irregularities can significantly influence the seismic behavior of buildings by inducing torsional effects, uneven load transfer, and localized stress concentrations, thereby increasing the risk of damage during strong earthquakes.\u003c/p\u003e\n\u003cp\u003eThe primary objective of this study is to analyze how horizontal geometric irregularities affect the behavior and seismic performance of RC high-rise buildings, with a focus on identifying associated risks and proposing effective mitigation strategies to enhance safety and resilience.\u003c/p\u003e\n\u003cp\u003eThis study will utilize a combination of analytical, numerical, and case study methods:\u003c/p\u003e\n\u003cp\u003e1.\u0026nbsp; \u0026nbsp;Analytical Methods: An exhaustive literature review of pertinent structural design codes\u003c/p\u003e\n\u003cp\u003eand guidelines (e.g., IS 1893:2016 and IS 13920:2016) pertaining to horizontal\u003c/p\u003e\n\u003cp\u003eirregularities.\u003c/p\u003e\n\u003cp\u003e2.\u0026nbsp; \u0026nbsp;Numerical Simulations: Finite Element Analysis (FEA) will be utilized to simulate\u003c/p\u003e\n\u003cp\u003edifferent forms of plan irregularities and analyze their effect on parameters such as\u003c/p\u003e\n\u003cp\u003ebase shear distribution, lateral displacement, torsion, and inter-storey drift.\u003c/p\u003e\n\u003cp\u003e3.\u0026nbsp; \u0026nbsp; Case Studies: Study of current high-rise buildings with reported horizontal\u003c/p\u003e\n\u003cp\u003eirregularities to study actual performance and cross-check simulation outcomes. The study will concentrate on major structural performance factors such as:\u003c/p\u003e\n\u003cp\u003ea)\u0026nbsp; \u0026nbsp;Seismic response and torsional behavior due to irregular plan geometry.\u003c/p\u003e\n\u003cp\u003eb)\u0026nbsp; \u0026nbsp; Load distribution patterns and stress concentrations within structural members.\u003c/p\u003e\n\u003cp\u003ec)\u0026nbsp; \u0026nbsp; Weak spots and potential failure modes due to irregular layouts.\u003c/p\u003e\n\u003cp\u003eThe findings will be contrasted against theoretical estimates and current code provisions, with comment on their import for practice. Possible mitigation strategies, e.g., optimal scheduling of shear walls, dual systems, and symmetrical stiffness distribution, will be investigated to reduce detrimental consequences.\u003c/p\u003e\n\u003cp\u003eThe research intends to deliver a comprehensive and applicable insight into the way horizontal geometric irregularities affect the seismic performance of RC high-rise buildings. The results will aid in developing better design practices and code provisions, leading to safer, more resilient building structures in earthquake-active regions. Research recommendations will cover new structural configurations and new materials in irregular plan designs..\u003c/p\u003e\n\u003ch4\u003e1.9 \u0026nbsp; Need for Research\u003c/h4\u003e\n\u003cp\u003eSeismic Zone V ranks as a zone of very high seismic activity, where the probability of frequent and strong earthquakes is high. Structures placed within this zone are at a large risk of struggling with stability and safety, particularly when they have horizontal geometric irregularities. These irregularities take place when the plan shape of the structure is asymmetrical, re-entrant (L-, T-, or U-shaped), or has major in mass, stiffness, or load distribution in the direction of the horizontal plane. Such aberrations can lead to torsional effects, non-uniform load transfer, and localized stress concentrations, increasing the structure towards seismic damage.\u003c/p\u003e\n\u003cp\u003eThe general purpose of this study is to determine and assess structural systems and design approaches which can adequately counteract the extra stresses and dynamic\u003c/p\u003e\n\u003cp\u003eThe primary objective of this research is to identify and evaluate structural systems and design strategies that can effectively address the additional stresses and dynamic\u003c/p\u003e\n\u003cp\u003ecomplexities introduced by \u003cstrong\u003ehorizontal irregularities\u0026nbsp;\u003c/strong\u003ein high-rise reinforced concrete buildings located in \u003cstrong\u003eSeismic Zone V\u003c/strong\u003e. The research focuses on developing approaches that enhance earthquake resistance while complying with relevant \u003cstrong\u003eIndian\u0026nbsp;Standards\u0026nbsp;(IS)\u003c/strong\u003e. This involves:\u003c/p\u003e\n\u003ch4\u003e1. \u0026nbsp; Assessing Structural Behavior:\u003c/h4\u003e\n\u003ch4\u003eInvestigation into how different structural systems and configurations react to seismic forces under the influence of horizontal irregularities, such as the influence of torsion, differential displacement, and in-plane stress distribution.\u003c/h4\u003e\n\u003ch4\u003e2. \u0026nbsp; Design Optimization:\u003c/h4\u003e\n\u003cp\u003eExploring design approaches\u0026mdash;such as symmetrical stiffness distribution, select placement of shear walls, and torsional balancing\u0026mdash;that can reduce the negative effect of plan irregularity and allow for more equitable seismic force distribution.\u003c/p\u003e\n\u003ch4\u003e3. \u0026nbsp; Safety Enhancement:\u003c/h4\u003e\n\u003cp\u003eMaintaining safety and functionality of horizontally irregular buildings during and after intense earthquakes through enhancement of redundancy, ductility, and overall structural resilience, thus decreasing the chances of partial or total collapse.\u003c/p\u003e\n\u003ch4\u003e4.\u0026nbsp; \u0026nbsp;Code\u0026nbsp;Compliance:\u003c/h4\u003e\n\u003cp\u003eSuggesting strengthening existing building codes (e.g., IS 1893:2016 and IS 13920:2016) to improve seismic design aspects of horizontally irregular buildings in high seismic areas.\u003c/p\u003e\n\u003cp\u003eIn the end, this study seeks to enhance the performance of horizontally irregular high-rise structures in Seismic Zone V, so that they are resilient to extreme seismic events without substantial structural or functional impairment. By combining analytical, numerical, and experimental methods, the study will contribute valuable insights for both practicing engineers and code development committees, helping to reduce earthquake- related risks and improve building safety in vulnerable regions.\u003c/p\u003e"},{"header":"2. LITERATURE REVIEW","content":"\u003cp\u003e\u003cstrong\u003e2.1\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eINTRODUCTION\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis chapter includes review of various research papers on the effect of irregularities on various building systems individually. An introduction about the effect of different structural systems\u0026nbsp;in\u0026nbsp;various\u0026nbsp;seismic\u0026nbsp;zones\u0026nbsp;is\u0026nbsp;reviewed\u0026nbsp;with\u0026nbsp;the\u0026nbsp;most\u0026nbsp;significant\u0026nbsp;investigations\u0026nbsp;reported\u0026nbsp;in\u0026nbsp;the literature also included.\u003c/p\u003e\n\u003ch5\u003e2.2 \u0026nbsp;REVIEW OF PREVIOUS STUDIES\u003c/h5\u003e\n\u003cp\u003e\u003cstrong\u003eDileshwar Rana et al. [1]\u0026nbsp;\u003c/strong\u003estudied\u0026nbsp;on\u0026nbsp;―Seismic\u0026nbsp;Analysis\u0026nbsp;of\u0026nbsp;Regular\u0026nbsp;\u0026amp;\u0026nbsp;Vertical\u0026nbsp;Geometric\u0026nbsp;Irregular RCC Framed Building‖. Researchers compared the shear force, a measure of earthquake force, across different\u0026nbsp;building\u0026nbsp;designs.\u0026nbsp;They\u0026nbsp;analyzed each floor individually\u0026nbsp;and compared\u0026nbsp;buildings of the same height but varying shapes. Buildings with setbacks (protruding sections) experienced higher shear forces than regular buildings. This effect became more significant with increasing setbacks. The study also investigated the bending moment, the twisting force buildings experience during earthquakes. Irregular buildings, including those with setbacks, faced higher bending moments than regular ones, regardless of height. This is due to the reduced stiffness of irregular structures, making them more susceptible to twisting. As a result, irregular buildings require more reinforcement to withstand these greater forces.\u003c/p\u003e\n\u003cp\u003eResponse spectrum analysis (RSA) was used to compare the earthquake response of irregular buildings to a regular one. \u003cstrong\u003eRavindra N. Shelke et al. [2]\u0026nbsp;\u003c/strong\u003eexamined\u0026nbsp;the\u0026nbsp;seismic\u0026nbsp;demand (forces\u0026nbsp;the structure needs to withstand) increases with higher seismic zones, requiring stronger buildings.\u003c/p\u003e\n\u003cp\u003eResponse\u0026nbsp;spectrum\u0026nbsp;method\u0026nbsp;is\u0026nbsp;recommended\u0026nbsp;for high-rise\u0026nbsp;or\u0026nbsp;irregular\u0026nbsp;buildings\u0026nbsp;as\u0026nbsp;it\u0026nbsp;provides\u0026nbsp;a\u0026nbsp;more realistic assessment compared to simpler methods.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eArup et al. [3]\u0026nbsp;\u003c/strong\u003ecarried out the research on ―Simplified\u0026nbsp;analysis method found effective for base- isolated buildings, including\u0026nbsp;irregular ones‖.\u0026nbsp;The study\u0026nbsp;found\u0026nbsp;that the simplified static analysis with a specific force distribution based on the first eigen mode provided results very close to the more complex response spectrum analysis, even for irregular buildings. This applies to both stiff and flexible\u0026nbsp;base\u0026nbsp;isolation\u0026nbsp;systems.\u0026nbsp;While\u0026nbsp;the\u0026nbsp;simplified\u0026nbsp;method\u0026nbsp;might slightly\u0026nbsp;underestimate\u0026nbsp;the\u0026nbsp;forces on the top floors of tall buildings, it generally provides more accurate results compared to another simplified method (linear distribution) which tends to overestimate top floor forces.\u003c/p\u003e\n\u003cp\u003e―Effects\u0026nbsp;of\u0026nbsp;vertical\u0026nbsp;irregularities\u0026nbsp;on\u0026nbsp;the\u0026nbsp;seismic\u0026nbsp;behaviour\u003c/p\u003e\n\u003cp\u003eof multi-storey buildings with base isolation‖ was researched by \u003cstrong\u003eN.I. Doudoumis et al. [4]\u0026nbsp;\u003c/strong\u003ewhere a comparison of simplified static analysis using a specific force distribution based on the building\u0026apos;s first vibration mode with a more complex multi-modal response spectrum analysis. The results showed that the simplified method provided very close results to the complex method for both regular and irregular base-isolated buildings, regardless of the base isolation system\u0026apos;s stiffness.\u003c/p\u003e\n\u003cp\u003eHowever, the simplified method might slightly underestimate forces on the top floors of tall buildings.\u0026nbsp;This\u0026nbsp;underestimation\u0026nbsp;depends\u0026nbsp;on\u0026nbsp;the\u0026nbsp;building\u0026apos;s\u0026nbsp;inherent damping\u0026nbsp;and\u0026nbsp;the\u0026nbsp;effectiveness of the base isolation system in damping vibrations. He first eigen ode distribution is more accurate, especially\u0026nbsp;for avoiding\u0026nbsp;overestimation of\u0026nbsp;forces\u0026nbsp;on\u0026nbsp;top\u0026nbsp;floors.\u0026nbsp;The\u0026nbsp;study\u0026nbsp;suggests\u0026nbsp;that\u0026nbsp;the simplified static analysis using the first eigen mode force distribution can be reliably applied to determine the seismic response of both regular and irregular base-isolated buildings.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOmkar M. Todkar et al. [5]\u0026nbsp;\u003c/strong\u003einvestigated\u0026nbsp;on\u0026nbsp;―Study\u0026nbsp;of\u0026nbsp;Seismic\u0026nbsp;Response\u0026nbsp;of\u0026nbsp;Multi-Storied\u0026nbsp;Vertical Irregular Building Due to Stiffness Irregularity‖. Study finds irregular buildings with sudden height changes move more under lateral loads. Uniform stiffness and regular shapes are ideal for better performance. Top floor irregularity may be slightly less harmful than lower ones, but avoiding irregularities is best.\u003c/p\u003e\n\u003cp\u003eIn\u0026nbsp;the\u0026nbsp;Comparison\u0026nbsp;of\u0026nbsp;Analysis\u0026nbsp;and\u0026nbsp;Design\u0026nbsp;of\u0026nbsp;Regular and\u003c/p\u003e\n\u003cp\u003eIrregular Configuration of Multi Story Building in Seismic Zones various parameter such as story shear force, mass irregularity, time history analysis, stiffness irregularity and vertical geometric irregularity. Were researched. In conclusion, \u003cstrong\u003eEl Sayed Abdel Naby et al. [6]\u0026nbsp;\u003c/strong\u003estated the shear force is highest in the first floor, decreasing towards the top, regardless of irregularity type. There is increase in base shear compared to regular buildings in mass irregularity. Stiffness irregularity also Reduces base shear but increases inter-story drifts. Geometry irregularity leads to higher displacements\u0026nbsp;in\u0026nbsp;upper\u0026nbsp;stories\u0026nbsp;compared\u0026nbsp;to\u0026nbsp;regular buildings,\u0026nbsp;converging\u0026nbsp;towards\u0026nbsp;the\u0026nbsp;lower\u0026nbsp;stories.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eR Ismail et al [7]\u0026nbsp;\u003c/strong\u003estudied\u0026nbsp;―Seismic performance for vertical\u0026nbsp;geometric\u0026nbsp;irregularity\u0026nbsp;frame\u003c/p\u003e\n\u003cp\u003estructures‖.\u0026nbsp;This study investigated the stress and displacement of buildings with vertical geometric irregularities (uneven shapes) subjected to seismic forces (earthquakes). The analysis considered both the normal building load and the seismic wave to understand the combined effect. Using eigenvalue analysis, the study identified the locations of maximum stress (critical points) under seismic loading. The overall results suggest that the vertical geometric irregularity frame can withstand the variations in loading and forces due to the earthquake. Additionally, the analysis of mode shapes revealed that the frame experiences swaying movements but the displacements are not\u003c/p\u003e\n\u003cp\u003esignificant.\u0026nbsp;In\u0026nbsp;conclusion,\u0026nbsp;the\u0026nbsp;study\u0026nbsp;suggests\u0026nbsp;that\u0026nbsp;the vertical\u0026nbsp;geometric\u0026nbsp;irregularity\u0026nbsp;in\u0026nbsp;this\u0026nbsp;specific case seems to be safe under the applied seismic performance loading.\u003c/p\u003e\n\u003cp\u003e―Irregularity effects on the seismic performance of l-shaped multi-story buildings‖ was examined by \u003cstrong\u003eMomen M. M. Ahmed et al [8].\u0026nbsp;\u003c/strong\u003eWhen a floor is not stiff enough (like an L-shape), the distribution of earthquake forces and the building\u0026apos;s response are significantly affected.\u003c/p\u003e\n\u003cp\u003eConsequences\u0026nbsp;of\u0026nbsp;neglecting\u0026nbsp;irregularity: Local\u0026nbsp;damage:\u0026nbsp;Uneven\u0026nbsp;force\u0026nbsp;distribution\u0026nbsp;can\u0026nbsp;cause\u0026nbsp;torsion and damage to outer columns, jeopardizing the building\u0026apos;s stability during earthquakes. Designing without considering irregularity can lead to miscalculations in the building\u0026apos;s seismic performance. Impact on functionality: Irregularity can lead to increased lateral deflections (swaying) and inter- story drifts (movement between floors), compromising the building\u0026apos;s functionality and potentially leading to performance failures.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMohd. Swaliheen et al. [9]\u0026nbsp;\u003c/strong\u003eresearched\u0026nbsp;―Seismic\u0026nbsp;Response\u0026nbsp;of\u0026nbsp;Vertically\u0026nbsp;Irregular\u0026nbsp;RC Frame\u0026nbsp;with\u003c/p\u003e\n\u003cp\u003eStiffness Irregularity\u0026nbsp;at Fourth Floor‖. Frame 1:\u0026nbsp;Vertically\u0026nbsp;irregular\u0026nbsp;(uneven floor\u0026nbsp;heights). Frame 2: Stiffness irregularity on a vertically irregular frame (combination of uneven floor heights and stiffness variations). Frame 2 (combined irregularity) performed worse than Frame 1 (only vertical irregularity) under lateral loads (earthquakes): Larger story displacements: Frame 2 experienced significant changes in displacement across all floors, indicating greater movement and potential structural weakness. Higher story drifts: Frame 2 showed extreme changes in story drift (movement between floors) at the level with the increased height, suggesting higher stress concentration and potential damage. Slightly higher story shear: Frame 2 experienced slightly higher forces at each floor level compared to Frame 1.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePravin S Patil et al. [10]\u0026nbsp;\u003c/strong\u003estudied \u003cstrong\u003e\u0026ldquo;\u003c/strong\u003eRCC\u0026nbsp;Structure\u0026nbsp;with\u0026nbsp;Different\u0026nbsp;Bracing\u0026nbsp;Configuration\u0026nbsp;on\u0026nbsp;Seismic Issues‖.\u0026nbsp;This study compared different types of bracing (like X, V, and eccentric) in two building models. They found that all bracing configurations can help control the building\u0026apos;s behavior under different loads, including earthquakes. X-bracing was the most effective, reducing forces, bending, and vibration time. Inverted\u0026nbsp;V and Eccentric Backward\u0026nbsp;were also good options. Overall,\u0026nbsp;X-bracing was the best at controlling horizontal movement. These findings suggest that bracing can be a valuable tool for designing tall buildings in the future.\u003c/p\u003e\n\u003cp\u003e―Analysis \u0026amp; design of G+20 RCC building using X-bracing system with base Isolator‖ was studied by \u003cstrong\u003eAshish R. Kondekar et al. [11]\u0026nbsp;\u003c/strong\u003eusing\u0026nbsp;X-bracing\u0026nbsp;can\u0026nbsp;help\u0026nbsp;prevent buildings\u0026nbsp;from\u0026nbsp;collapsing\u0026nbsp;and reduce the forces on the building during an earthquake. This makes the building more stable.\u003c/p\u003e\n\u003cp\u003eHowever,\u0026nbsp;it\u0026nbsp;can\u0026nbsp;also\u0026nbsp;increase\u0026nbsp;the\u0026nbsp;displacement\u0026nbsp;of\u0026nbsp;each\u0026nbsp;floor.\u0026nbsp;Overall,\u0026nbsp;X-bracing\u0026nbsp;can\u0026nbsp;improve\u0026nbsp;a building\u0026apos;s earthquake resistance and potentially reduce the amount of reinforcing steel needed.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRohan\u0026nbsp;Chavan\u0026nbsp;et\u0026nbsp;al\u003c/strong\u003e. \u003cstrong\u003e[12]\u0026nbsp;\u003c/strong\u003estudied\u0026nbsp;―Seismic\u0026nbsp;Analysis\u0026nbsp;of\u0026nbsp;Irregular\u0026nbsp;RC\u0026nbsp;Structure\u0026nbsp;with\u0026nbsp;Cross-Bracing System‖. This study analyzed the effectiveness of steel bracing in improving the earthquake resistance of\u0026nbsp;a 11-story\u0026nbsp;building. The results\u0026nbsp;showed\u0026nbsp;that adding\u0026nbsp;steel bracing, even with\u0026nbsp;a minimal increase in weight, significantly reduces lateral movement, bending forces, and story drift. This makes\u0026nbsp;the\u0026nbsp;building\u0026nbsp;more\u0026nbsp;stable\u0026nbsp;during\u0026nbsp;earthquakes.\u0026nbsp;Both\u0026nbsp;X-bracing\u0026nbsp;and\u0026nbsp;other\u0026nbsp;types\u0026nbsp;of\u0026nbsp;bracing\u0026nbsp;were found\u0026nbsp;to be\u0026nbsp;effective\u0026nbsp;in improving\u0026nbsp;structural performance.\u0026nbsp;These findings suggest that steel bracing can be a valuable tool in designing earthquake-resistant buildings.\u003c/p\u003e\n\u003ch5\u003e2.3\u0026nbsp;CRITICAL\u0026nbsp;APPRAISAL\u0026nbsp;OF\u0026nbsp;LITERATURE\u003c/h5\u003e\n\u003cp\u003eThe reviewed studies collectively highlight several critical points regarding the impact of vertical geometric irregularities on the seismic performance of RC high-rise buildings. Irregular buildings, particularly those with setbacks or uneven floor heights, experience higher shear forces and\u0026nbsp;bending\u0026nbsp;moments\u0026nbsp;due\u0026nbsp;to\u0026nbsp;reduced\u0026nbsp;stiffness,\u0026nbsp;necessitating\u0026nbsp;additional\u0026nbsp;reinforcement.\u0026nbsp;The\u0026nbsp;response spectrum analysis method is recommended for more accurate assessment of seismic response in irregular and high-rise buildings.\u003c/p\u003e\n\u003cp\u003eSimplified static analysis methods, especially those using the first eigen mode force distribution, can provide reliable results similar to more complex methods, although they may slightly underestimate forces at the top floors. Abrupt changes in height and stiffness irregularities cause larger lateral displacements and story drifts, which can undermine structural integrity.\u003c/p\u003e\n\u003cp\u003eVertical geometric irregularities cause higher upper-story displacements, more base shear in the presence of mass irregularity, and certain stress concentrations due to seismic loading. Successful seismic design should control these irregularities to avoid local damage\u003c/p\u003e\n\u003cp\u003eto provide uniform distribution of forces, and ensure the functioning of buildings before, during, and after earthquakes.\u003c/p\u003e\n\u003cp\u003eIn total, these results highlight the importance of strong design measures and precise seismic analysis to promote the longevity and safety of irregular RC high-rise buildings in seismically active regions.\u003c/p\u003e"},{"header":"3. METHODOLOGY","content":"\u003cp\u003e\u003cstrong\u003e3.1\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eINTRODUCTION\u003c/strong\u003e\u003cstrong\u003e\u003cbr\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis chapter provides an overview of the different methods used for the analysis of building systems. Furthermore, it delves into the complexities of structural analysis software ETABS, offering detailed information on the modeling processes, loading as well as analysis and within this particular software.\u003c/p\u003e\n\u003ch3\u003e3.2\u0026nbsp;Response\u0026nbsp;Spectrum\u0026nbsp;Analysis\u003c/h3\u003e\n\u003cp\u003eResponse Spectrum Analysis (RSA) is a most widely accepted and code recommended practices for seismic assessment of structures, particularly in situations where irregularities in mass distribution or geometry render the dynamic behavior complicated. For horizontally irregular structures, the response to earthquakes is extremely sensitive to torsional behaviors, eccentricity of mass, and stiffness variation over the plan..\u003c/p\u003e\n\u003cp\u003eIn RSA, the structure is modeled as a multi-degree-of-freedom (MDOF) system, which is then decomposed into a series of \u003cstrong\u003esingle-degree-of-freedom (SDOF) modal shapes\u0026nbsp;\u003c/strong\u003ethrough eigenvalue analysis. Each mode is subjected to the design response spectrum as per \u003cstrong\u003eIS 1893 (Part 1): 2016\u003c/strong\u003e, considering the spectral accelerations corresponding to the natural time periods. For horizontally irregular structures, \u003cstrong\u003etorsional modes\u0026nbsp;\u003c/strong\u003eare given special attention, and accidental eccentricity (minimum 5% of building dimension perpendicular to the direction of loading) is included to account for unforeseen asymmetries.\u003c/p\u003e\n\u003cp\u003eThe output of RSA includes modal displacements, storey shears, storey drifts, and base shear values, which are combined using modal combination rules such as \u003cstrong\u003eSquare Root of the Sum of Squares (SRSS)\u0026nbsp;\u003c/strong\u003eor \u003cstrong\u003eComplete Quadratic Combination (CQC)\u003c/strong\u003e, as recommended by the code for closely spaced modes. This approach ensures that irregularities in plan shape, stiffness distribution, and mass eccentricity are properly captured, leading to a more reliable seismic design.\u003c/p\u003e\n\u003cp\u003eThe key benefit of applying RSA to horizontally irregular structures is that it can calculate torsional amplification and determine the most important modes that affect\u003c/p\u003e\n\u003cp\u003ethe design. This facilitates focused strengthening interventions, for example, enhancing flexible wings of L-shaped or T-shaped plans\u0026apos; stiffness, redistributing mass to lower eccentricity, or adding supplemental damping devices.\u003c/p\u003e\n\u003ch4\u003e3.3\u0026nbsp;Introduction\u0026nbsp;to\u0026nbsp;Etabs\u0026nbsp;Software\u003c/h4\u003e\n\u003cp\u003eETABS 22 (Extended Three-Dimensional Analysis of Building Systems) is an substantial improvement over previous releases, with more powerful tools for modeling,\u003c/p\u003e\n\u003cp\u003eanalyzing, and designing intricate building geometries, such as those with horizontal plan irregularities. Its enhanced finite element solver, torsional irregularity checks,\u003c/p\u003e\n\u003cp\u003eand visualization capabilities make it especially well-suited to evaluate buildings that are not regular configurations.\u003c/p\u003e\n\u003cp\u003eETABS 22 enables engineers to develop an accurate three-dimensional representation of the irregular structure, including correct geometry, material properties, support conditions, and load paths. Make provisions for such irregularities as re-entrant corners, setbacks, wings, and non-uniform stiffness distribution can be represented exactly according to architectural plans, making certain that the dynamic behavior is properly modeled in the analysis..\u003c/p\u003e\n\u003cp\u003eWhen\u0026nbsp;modeling\u0026nbsp;a\u0026nbsp;horizontally\u0026nbsp;irregular\u0026nbsp;building\u0026nbsp;in\u0026nbsp;ETABS\u0026nbsp;22,\u0026nbsp;the\u0026nbsp;process\u0026nbsp;involves\u0026nbsp;several additional considerations compared to a regular plan:\u003c/p\u003e\n\u003ch4\u003e3.3.1 \u0026nbsp; \u0026nbsp;Grid and Geometry Definition\u003c/h4\u003e\n\u003cp\u003eThe structural grid is created to reflect the irregular floor plan. For example, an L- shaped\u0026nbsp;or\u0026nbsp;T-shaped\u0026nbsp;configuration\u0026nbsp;is\u0026nbsp;modeled\u0026nbsp;directly,\u0026nbsp;without\u0026nbsp;artificially\u0026nbsp;dividing\u0026nbsp;it into multiple rectangles. This ensures accurate stiffness and torsional response calculation.\u003c/p\u003e\n\u003ch4\u003e3.3.2 \u0026nbsp; \u0026nbsp;Material and Section Properties\u003c/h4\u003e\n\u003cp\u003eConcrete,\u0026nbsp;steel,\u0026nbsp;and\u0026nbsp;composite\u0026nbsp;material\u0026nbsp;properties\u0026nbsp;are\u0026nbsp;defined\u0026nbsp;as\u0026nbsp;per\u0026nbsp;IS\u0026nbsp;456:2000,\u0026nbsp;IS 800:2007, or relevant codes. Section dimensions vary\u0026nbsp;according\u0026nbsp;to the plan shape to optimize stiffness distribution.\u003c/p\u003e\n\u003ch4\u003e3.3.3 \u0026nbsp; \u0026nbsp;Diaphragm Assignment\u003c/h4\u003e\n\u003cp\u003e\u003cstrong\u003ea) \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eRigid\u0026nbsp;Diaphragm\u003c/strong\u003e: Applied to floors with high in-plane stiffness (e.g., RC slabs without large openings).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eb) \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eSemi-Rigid\u0026nbsp;Diaphragm\u003c/strong\u003e: Applied where the floor has significant flexibility or openings, enabling the software to capture in-plane distortion effects, which are especially important in irregular layouts.\u003c/p\u003e\n\u003ch4\u003e3.3.4 \u0026nbsp; \u0026nbsp;Mass Source and Accidental Eccentricity\u003c/h4\u003e\n\u003cp\u003eMass\u0026nbsp;source\u0026nbsp;includes\u0026nbsp;dead\u0026nbsp;load\u0026nbsp;+\u0026nbsp;appropriate\u0026nbsp;live\u0026nbsp;load\u0026nbsp;portion\u0026nbsp;as\u0026nbsp;per\u0026nbsp;IS\u0026nbsp;1893:2016. Accidental eccentricity is included either automatically through ETABS settings or manually by offsetting the center of mass.\u003c/p\u003e\n\u003ch4\u003e3.3.5 \u0026nbsp; \u0026nbsp;Load Application and Combination\u003c/h4\u003e\n\u003cp\u003eSeismic loads are generated using IS 1893:2016 parameters, ensuring that plan irregularity\u0026nbsp;effects\u0026nbsp;are\u0026nbsp;considered.\u0026nbsp;Load\u0026nbsp;combinations\u0026nbsp;follow\u0026nbsp;IS\u0026nbsp;456:2000\u0026nbsp;and\u0026nbsp;IS 875 guidelines.\u003c/p\u003e\n\u003ch4\u003e3.3.6 \u0026nbsp; \u0026nbsp;Meshing and Shell Element Assignment\u003c/h4\u003e\n\u003cp\u003eSlabs\u0026nbsp;are\u0026nbsp;modeled\u0026nbsp;using\u0026nbsp;shell\u0026nbsp;elements\u0026nbsp;with\u0026nbsp;appropriate\u0026nbsp;meshing\u0026nbsp;to\u0026nbsp;capture localized stress concentrations due to irregular geometry.\u003c/p\u003e\n\u003cp\u003e3.3.7 \u003cstrong\u003eMembrane Elements\u0026nbsp;\u003c/strong\u003efor non-load bearing diaphragms.\u003c/p\u003e\n\u003cp\u003e3.3.8 \u003cstrong\u003eShell Elements\u0026nbsp;\u003c/strong\u003efor load-bearing slabs that contribute to stiffness.\u003c/p\u003e\n\u003ch4\u003e3.3.9 \u0026nbsp; \u0026nbsp;Modal Analysis and RSA Execution\u003c/h4\u003e\n\u003cp\u003eEigenvalue analysis is performed to identify natural periods and mode shapes, paying\u0026nbsp;special\u0026nbsp;attention\u0026nbsp;to\u0026nbsp;torsional\u0026nbsp;modes.\u0026nbsp;RSA\u0026nbsp;is\u0026nbsp;then\u0026nbsp;executed\u0026nbsp;using\u0026nbsp;the\u0026nbsp;design response spectrum.\u003c/p\u003e\n\u003ch4\u003e3.3.10 \u0026nbsp;Post-Processing and Code Checks\u003c/h4\u003e\n\u003cp\u003eResults\u0026nbsp;are\u0026nbsp;reviewed\u0026nbsp;for\u0026nbsp;storey\u0026nbsp;drift\u0026nbsp;limits,\u0026nbsp;base\u0026nbsp;shear\u0026nbsp;distribution,\u0026nbsp;and\u0026nbsp;torsional irregularity ratios as per IS 1893:2016, Clause 7.1.2. Any exceedance prompts design modifications.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.4\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eAnalysis in ETABS 2018\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAnalysis\u0026nbsp;in\u0026nbsp;structural\u0026nbsp;analysis\u0026nbsp;software\u0026nbsp;ETABS\u0026nbsp;involves\u0026nbsp;simulating\u0026nbsp;and\u0026nbsp;evaluating\u0026nbsp;the\u0026nbsp;behavior\u0026nbsp;of\u0026nbsp;a structure under various load conditions. ETABS employs advanced computational techniques to calculate structural responses such as displacements, forces, moments, and stresses.\u003c/p\u003e\n\u003cp\u003eThe\u0026nbsp;analysis\u0026nbsp;process\u0026nbsp;in\u0026nbsp;ETABS\u0026nbsp;typically\u0026nbsp;involves\u0026nbsp;the\u0026nbsp;following\u0026nbsp;steps:\u003c/p\u003e\n\u003cp\u003ei) \u0026nbsp; Model Creation\u003c/p\u003e\n\u003cp\u003eThe structure is first modeled in ETABS, where the geometry, material properties, and support conditions\u0026nbsp;are\u0026nbsp;defined.\u0026nbsp;This\u0026nbsp;includes\u0026nbsp;creating\u0026nbsp;elements\u0026nbsp;such\u0026nbsp;as\u0026nbsp;beams,\u0026nbsp;columns,\u0026nbsp;slabs,\u0026nbsp;and\u0026nbsp;walls, assigning appropriate cross-sectional properties and material properties.\u003c/p\u003e\n\u003cp\u003eii) \u0026nbsp; Loading\u003c/p\u003e\n\u003cp\u003eDifferent\u0026nbsp;types\u0026nbsp;of\u0026nbsp;loads,\u0026nbsp;such\u0026nbsp;as\u0026nbsp;dead\u0026nbsp;loads,\u0026nbsp;live\u0026nbsp;loads,\u0026nbsp;wind\u0026nbsp;loads,\u0026nbsp;seismic\u0026nbsp;loads,\u0026nbsp;and\u0026nbsp;temperature loads, are applied to the structure. Loads can be applied directly to elements or through load patterns, which define the spatial distribution of loads on the structure.\u003c/p\u003e\n\u003cp\u003eiii) \u0026nbsp; Analysis Types\u003c/p\u003e\n\u003cp\u003eETABS\u0026nbsp;offers\u0026nbsp;various\u0026nbsp;analysis\u0026nbsp;types\u0026nbsp;to\u0026nbsp;evaluate\u0026nbsp;the\u0026nbsp;structural\u0026nbsp;response.\u0026nbsp;The\u0026nbsp;most\u0026nbsp;common analysis types include:\u003c/p\u003e\n\u003cp\u003ea) \u0026nbsp; Static Analysis\u003c/p\u003e\n\u003cp\u003eT3.5his analysis calculates the structural response under steady loads, without considering the\u0026nbsp;effect\u0026nbsp;of\u0026nbsp;time\u0026nbsp;or\u0026nbsp;dynamic\u0026nbsp;factors.\u0026nbsp;It\u0026nbsp;is\u0026nbsp;suitable\u0026nbsp;for\u0026nbsp;most\u0026nbsp;normal\u0026nbsp;load\u0026nbsp;conditions\u0026nbsp;and\u0026nbsp;can provide information on member forces, displacements, and support reactions.\u003c/p\u003e\n\u003cp\u003eb) \u0026nbsp; Dynamic Analysis\u003c/p\u003e\n\u003cp\u003eETABS conducts modal analysis to find out the natural frequencies, mode shapes, and modal participation factors of the structure. Response spectrum analysis, time history analysis, or any other dynamic analysis technique can be used to compute the dynamic response..\u003c/p\u003e\n\u003cp\u003ec) \u0026nbsp; Results and Post-processing\u003c/p\u003e\n\u003cp\u003eAfter completion of analysis, ETABS yields comprehensive results including displacements, member forces, moments, shear forces, and other parameters. Results can be visualized using different graphs, contour plots and animations. Engineers are able to examine the structural integrity, determine the critical zones and take decisions based on the analysis results..\u003c/p\u003e\n\u003cp\u003eOverall,\u0026nbsp;analysis\u0026nbsp;in ETABS allows engineers to\u0026nbsp;evaluate\u0026nbsp;the\u0026nbsp;structural behavior,\u0026nbsp;assess\u0026nbsp;the safety and\u0026nbsp;performance\u0026nbsp;of\u0026nbsp;the\u0026nbsp;design,\u0026nbsp;and\u0026nbsp;optimize\u0026nbsp;the\u0026nbsp;structure\u0026apos;s\u0026nbsp;design\u0026nbsp;and\u0026nbsp;detailing.\u0026nbsp;It\u0026nbsp;plays\u0026nbsp;a\u0026nbsp;crucial\u003c/p\u003e\n\u003cp\u003erole\u0026nbsp;in\u0026nbsp;ensuring\u0026nbsp;structural\u0026nbsp;integrity,\u0026nbsp;meeting\u0026nbsp;design\u0026nbsp;requirements,\u0026nbsp;and\u0026nbsp;enhancing\u0026nbsp;the\u0026nbsp;overall\u0026nbsp;safety and efficiency of the structure.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3.5\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eDesign parameters in ETABS\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDesign in ETABS is the check on the structural elements of a building to ensure that they are in accordance with the necessary design standards and criteria. ETABS offers a full range of design\u003c/p\u003e\n\u003cp\u003etools that help engineers design structures which are safe, efficient, and conform to relevant design codes and laws. The process of design in ETABS generally includes the following steps:\u003c/p\u003e\n\u003cp\u003ei. \u0026nbsp; \u0026nbsp;Code Selection\u003c/p\u003e\n\u003cp\u003eEngineers define the design code or standard to be followed during the design process. ETABS accommodates several national and international design codes, including ACI (American Concrete Institute), AISC (American Institute of Steel Construction), Eurocode, and numerous others. The code chosen includes the criteria and requirements for structural design.Design Load Combinations ETABS automatically generates design load combinations based on the selected code and the defined load patterns. These combinations consider various load cases and load factors to simulate different load scenarios. Common load combinations include dead load, live load, wind load, seismic load, and temperature load.\u003c/p\u003e\n\u003cp\u003ei. \u0026nbsp; \u0026nbsp; Design Checks\u003c/p\u003e\n\u003cp\u003eETABS\u0026nbsp;performs\u0026nbsp;a\u0026nbsp;series\u0026nbsp;of\u0026nbsp;design\u0026nbsp;checks\u0026nbsp;on\u0026nbsp;different\u0026nbsp;structural\u0026nbsp;elements\u0026nbsp;to\u0026nbsp;verify\u0026nbsp;their\u0026nbsp;strength, stability, and serviceability. These checks may include:\u003c/p\u003e\n\u003cp\u003ea) \u0026nbsp; Concrete Design\u003c/p\u003e\n\u003cp\u003eETABS\u0026nbsp;checks\u0026nbsp;the\u0026nbsp;design\u0026nbsp;of\u0026nbsp;concrete\u0026nbsp;elements\u0026nbsp;such\u0026nbsp;as\u0026nbsp;beams,\u0026nbsp;columns,\u0026nbsp;slabs,\u0026nbsp;and\u0026nbsp;walls\u0026nbsp;for factors such as flexural strength, shear capacity, and axial load resistance.\u003c/p\u003e\n\u003cp\u003eb) \u0026nbsp; Steel Design\u003c/p\u003e\n\u003cp\u003eETABS\u0026nbsp;assesses\u0026nbsp;the\u0026nbsp;design\u0026nbsp;of\u0026nbsp;steel\u0026nbsp;elements,\u0026nbsp;including\u0026nbsp;beams,\u0026nbsp;columns,\u0026nbsp;and\u0026nbsp;braces,\u0026nbsp;for\u0026nbsp;factors such as strength, buckling resistance, and connection design. It verifies that the steel members comply with the specified code provisions.\u003c/p\u003e\n\u003cp\u003ec) \u0026nbsp; Seismic Design\u003c/p\u003e\n\u003cp\u003eETABS\u0026nbsp;provides\u0026nbsp;specialized\u0026nbsp;seismic\u0026nbsp;design\u0026nbsp;capabilities\u0026nbsp;to make sure\u0026nbsp;that\u0026nbsp;structures\u0026nbsp;can\u0026nbsp;withstand earthquake forces. It checks factors such as seismic base shear, inter-storey drift, and member ductility to ensure compliance with seismic design codes.\u003c/p\u003e\n\u003cp\u003ed) \u0026nbsp; Design Results\u003c/p\u003e\n\u003cp\u003eAfter\u0026nbsp;the\u0026nbsp;design\u0026nbsp;checks\u0026nbsp;are\u0026nbsp;performed, Engineers\u0026nbsp;can\u0026nbsp;review\u0026nbsp;these\u0026nbsp;results\u0026nbsp;to\u0026nbsp;assess\u0026nbsp;the\u0026nbsp;adequacy\u0026nbsp;of\u0026nbsp;the\u0026nbsp;design\u0026nbsp;and\u0026nbsp;make necessary adjustments if needed.\u003c/p\u003e\n\u003cp\u003ee) \u0026nbsp; Design Optimization\u003c/p\u003e\n\u003cp\u003eETABS enables the engineers to iterate and optimize the design by modifying a number of parameters like member size, reinforcement detailing, and connection type. This iterative process assists in obtaining an optimized design that satisfies all necessary design criteria. With the use of ETABS design capabilities, the engineers can be assured that their structures are safe, cost-effective, and compliant with industry standards. ETABS simplifies the design process by it will automate much of the intricate computation and verification, enabling engineers to concentrate on key design choices and verify the structural integrity of the building.\u003c/p\u003e"},{"header":"4. MODELLING AND ANALYSIS","content":"\u003cp\u003e\u003cstrong\u003e4.1 Introduction\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;This section describes the modeling and analysis technique used to assess the seismic performance of the suggested horizontally irregular, symmetric and unsymmetric G+28 high-rise residential building designed with a Structural Wall System in Seismic Zone V. The analysis was conducted employing ETABS 2022, which is renowned for its powerful ability to model complicated building systems as per applicable IS codes. The structural system contains a centrally positioned reinforced concrete core, where vertical circulation elements like lift shafts and staircases are housed. To provide better lateral stiffness and restrict drift, shear walls are located at specified positions, forming an integrated structural system that can effectively resist seismic forces. The structural building was simulated using beam and column elements as frame members, whereas the slabs were specified as shell elements in order to simulate both in-plane and out-of-plane characteristics. Rigid diaphragm constraints were applied at every floor level in order to mimic the realistic collective displacement of the floor slabs under lateral loading.Design loads were defined based on IS 875 (Part 1, Part 2, and Part 3) for dead, live, and wind loads respectively, while seismic parameters were specified according to IS 1893 (Part 1): 2016 for Zone V with medium soil conditions. Load combinations were automatically generated in ETABS to ensure that all critical loading scenarios were accounted for as per codal provisions. To study the dynamic response, a modal analysis was first conducted to extract the fundamental natural periods and mode shapes of the building. This was followed by a Response Spectrum Analysis (RSA), which provides a practical means to estimate the peak structural response to seismic excitations without requiring a full time history record. The response spectrum was defined in accordance with IS 1893, considering a damping ratio of 5% for reinforced concrete structures. Key output parameters such as base shear, lateral displacements, inter-storey drift, and mode shapes were carefully reviewed. The results indicate that the core and outrigger system effectively enhances the lateral stiffness of the building and keeps storey drift within permissible limits. This confirms the suitability of the selected structural system for a high-rise building in a high seismic risk zone.\u003c/p\u003e\n\u003ch5\u003e4.2\u0026nbsp;BUILDING\u0026nbsp;PARAMETERS\u003c/h5\u003e\n\u003cp\u003eThis\u0026nbsp;study\u0026nbsp;primarily\u0026nbsp;focuses\u0026nbsp;on\u0026nbsp;the\u0026nbsp;dynamic\u0026nbsp;analysis\u0026nbsp;of\u0026nbsp;a\u0026nbsp;high\u0026nbsp;rise\u0026nbsp;building\u0026nbsp;structure\u0026nbsp;by considering the seismic zone V for Shillong location on the North-East of India. The overall analysis is done for a Twenty-eight storey high rise building structure in ETABS software.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;Table: 4.1 Building Parameters\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 239px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParameters\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDetails\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 239px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;Area (mm\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e21.5X116.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 239px;\"\u003e\n \u003cp\u003ePlinth\u0026nbsp;Beam\u0026nbsp;Size (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e300X450\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 239px;\"\u003e\n \u003cp\u003eFloor\u0026nbsp;Beam\u0026nbsp;Size (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e300X700\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 239px;\"\u003e\n \u003cp\u003eShear\u0026nbsp;Wall (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e300X1000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 239px;\"\u003e\n \u003cp\u003eSlab\u0026nbsp;Thickness\u0026nbsp;(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e150\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 239px;\"\u003e\n \u003cp\u003eExternal\u0026nbsp;Wall\u0026nbsp;Thickness (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e300\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 239px;\"\u003e\n \u003cp\u003eFloor\u0026nbsp;to\u0026nbsp;Floor\u0026nbsp;Height\u0026nbsp;(mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e3000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 239px;\"\u003e\n \u003cp\u003eHeight\u0026nbsp;of\u0026nbsp;Building (mm)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e84000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eTable 4.1 provides information about various aspects of a building, including the plan area, beam and column size, slab thickness, and height.\u003c/p\u003e\n\u003ch5\u003e4.2\u0026nbsp;LOADING\u0026nbsp;PARAMETERS\u003c/h5\u003e\n\u003cp\u003eCalculating loading parameters in structural analysis involves determining load types and magnitudes, combining them into load combinations, considering load distribution and application points, calculating load effects using structural mechanics principles, and comparing them to element capacities for stability and safety. Understanding load types and their effects is crucial, such as assuming concrete density as 25 kN/m\u0026sup3; and brick density as 18 kN/m\u0026sup3;.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4.2.1\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eSeismic Load Parameters\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAs per IS 1893 Part I 2016, the Indian standard code for earthquake loads on buildings and structures, earthquake load parameters are defined to ensure the structural safety and stability of buildings. The soil type considered for the analysis is Type II\u0026nbsp;soil (Medium \u0026ndash; stiff). The importance factor,\u0026nbsp;response\u0026nbsp;reduction\u0026nbsp;factor,\u0026nbsp;time\u0026nbsp;period,\u0026nbsp;design\u0026nbsp;acceleration\u0026nbsp;coefficient\u0026nbsp;is\u0026nbsp;given\u0026nbsp;in\u0026nbsp;the\u0026nbsp;table\u0026nbsp;4.2 below:\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable:4.2 Earthquake Load Details for Building\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 312px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eParticulars\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eDetails\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 312px;\"\u003e\n \u003cp\u003eCity\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003eShillong\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 312px;\"\u003e\n \u003cp\u003eSeismic Zone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003eV\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 312px;\"\u003e\n \u003cp\u003eImportance\u0026nbsp;Factor\u0026nbsp;(I)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e1.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 312px;\"\u003e\n \u003cp\u003eResponse\u0026nbsp;Reduction\u0026nbsp;Factor (R)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 312px;\"\u003e\n \u003cp\u003eTime\u0026nbsp;Period (seconds)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e2.069\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 312px;\"\u003e\n \u003cp\u003eDesign\u0026nbsp;Acceleration\u0026nbsp;Coefficient (Ah)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e0.036\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003ch5\u003e4.3\u0026nbsp;LOAD\u0026nbsp;COMBINATIONS\u003c/h5\u003e\n\u003cp\u003eIn the limit state design of reinforced concrete structures, load combinations are determined based on the guidelines provided in IS Code 456 Table 18. These load combinations are essential for ensuring the safety and reliability of the structures. The table specifies the partial safety factors to be applied to different types of loads, such as dead load, live load, wind load, and earthquake load. By considering these load combinations, the various possible scenarios and design structures that can withstand the expected loads and forces are defined below:\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eTable 4.3 Static Earthquake Load Combinations\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEQ\u0026nbsp;LOAD COMBOS\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNAME\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;+\u0026nbsp;1.5\u0026nbsp;EQPX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eD9EQPX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;+\u0026nbsp;1.5\u0026nbsp;EQNX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eD9EQNX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;+\u0026nbsp;1.5EQPY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eD9EQPY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;+\u0026nbsp;1.5EQNY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eD9EQNY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;\u0026ndash;\u0026nbsp;1.5\u0026nbsp;EQPX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eD9EQPNX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;\u0026ndash;\u0026nbsp;1.5\u0026nbsp;EQNX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eD9EQNNX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;\u0026ndash;1.5EQPY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eD9EQPNY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;\u0026ndash; 1.5EQNY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eD9EQNNY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;LL\u0026nbsp;+ EQPX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQPX12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;LL\u0026nbsp;+ EQNX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQNX12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;LL\u0026nbsp;+ EQPY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQPY12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;LL\u0026nbsp;+ EQNY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQNY12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;LL\u0026nbsp;\u0026ndash;\u0026nbsp;EQPX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQPNX12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;LL\u0026nbsp;\u0026ndash;\u0026nbsp;EQNX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQNNX12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;LL\u0026nbsp;\u0026ndash;\u0026nbsp;EQPY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQPNY12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;LL\u0026nbsp;\u0026ndash;\u0026nbsp;EQNY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQNNY12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;EQPX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQPX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;EQNX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQNX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;EQPY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQPY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;EQNY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQNY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;\u0026ndash;\u0026nbsp;EQPX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQPNX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;\u0026ndash;\u0026nbsp;EQNX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQNNX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;\u0026ndash;\u0026nbsp;EQPY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQNNY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 176px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;\u0026ndash;\u0026nbsp;EQNY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 107px;\"\u003e\n \u003cp\u003eEQNNY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4.4 Dynamic Earthquake Load Combinations\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSPEC\u0026nbsp;LOAD COMBOS\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNAME\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;+\u0026nbsp;1.5SPECX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eD9SPECX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;+\u0026nbsp;1.5SPECY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eD9SPECY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;\u0026ndash; 1.5SPECX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eD9SPECNX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e0.9DL\u0026nbsp;\u0026ndash; 1.5SPECY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eD9SPECNY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL+\u0026nbsp;LL\u0026nbsp;+\u0026nbsp;SPECX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eSPECX12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;LL\u0026nbsp;+ SPECY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eSPECY12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;LL\u0026nbsp;\u0026ndash;\u0026nbsp;SPECX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eSPECNX12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e1.2\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;LL\u0026nbsp;\u0026ndash;\u0026nbsp;SPECY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eSPECNY12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;SPECX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eSPECX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;+\u0026nbsp;SPECY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eSPECY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;\u0026ndash; SPECX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eSPECNX15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 197px;\"\u003e\n \u003cp\u003e1.5\u0026nbsp;(DL\u0026nbsp;\u0026ndash; SPECY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 111px;\"\u003e\n \u003cp\u003eSPECNY15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4.5 Serviceability Load Combinations\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eEQ COMBO\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNAME\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+EQPX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDEQPX\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+EQNX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDEQNX\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+EQPY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDEQPY\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+EQNY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDEQNY\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL-EQPX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDEQPNX\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL-EQNX\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDEQNNX\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL-EQPY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDEQPNY\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL-EQNY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDEQNNY\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+0.8(LL+EQPX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDLEQPX8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+0.8(LL+EQNX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDLEQNX8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+0.8(LL+EQPY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDLEQPY8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+0.8(LL+EQNY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDLEQNY8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+0.8(LL-EQPX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDLEQPNX8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+0.8(LL-EQNX)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDLEQNNX8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+0.8(LL-EQPY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDLEQPNY8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 148px;\"\u003e\n \u003cp\u003eDL+0.8(LL-EQNY)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eDLEQNNY8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e4.4 STRUCTURAL SYSTEMS MODELING ETABS SOFTWARE\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn the ETABS software, two plans are designed including\u0026nbsp;structural wall system. These structural systems are analyzed under various load combinations mentioned in the above tables. Table 4.6 provides\u0026nbsp;detailed\u0026nbsp;information\u0026nbsp;about\u0026nbsp;all\u0026nbsp;three\u0026nbsp;models,\u0026nbsp;including\u0026nbsp;their\u0026nbsp;respective\u0026nbsp;structural\u0026nbsp;systems. This data helps in evaluating the performance and behavior of each model under the seismic conditions under different structural systems, allowing\u0026nbsp;to study various parameters such as storey displacement, storey drift and storey stiffness.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4.6 Structural Systems Models in ETABS\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eModel\u0026nbsp;No.\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 305px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eType\u0026nbsp;of\u0026nbsp;Structural System\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 305px;\"\u003e\n \u003cp\u003eStructural\u0026nbsp;Wall\u0026nbsp;System\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 305px;\"\u003e\n \u003cp\u003eStructural\u0026nbsp;Wall\u0026nbsp;System\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eThe following figures reflect the comprehensive plan, 3D visualization, and loading analysis created with the ETABS software. From the figures, different architectural plan of structural wall system utilized in various models is shown. The comprehensive plan identifies the project goals, strategies, and activities in a systematic and thorough way. The 3Dvisualization provides the visual presentation of the structures such that better understanding of their overall shape and geometry. Moreover, the loading analysis gives an idea of how various loads, including gravity and wind forces influence the structural behavior of every model.\u003c/p\u003e\n\u003cp\u003eIn Figure 2(a) \u0026amp; 2(b), showcase the shear wall structural system employed in this particular model. The figure visually presents the layout and arrangement of the shear walls within the model, providing insights into the structural configuration. For the analysis, a consistent thickness of 300 mm is considered for the shear walls. The structure incorporates a central core and shear walls positioned along with some walls equally distributed on the both the axes. These shear walls, including the core of the structure, share the same type and dimensions, ensuring uniformity throughout the design.\u003c/p\u003e\n\u003cp\u003eFigure 4.3 \u0026amp; 4.4 provides a visual representation of the Z shaped structure having structural wall system utilized in Model II. The figure showcases the arrangement and configuration of the horizontally irregular structure whose ratio of re-entrant corner is greater that 1.5(IS 1893-2016, Cl- no.7.1, Pg-no.15). A central reinforced concrete or composite core is employed as the primary vertical and lateral load-resisting element. This core accommodates essential building services such as lift shafts, stairwells, and utility ducts, making it a functionally integrated component of the building design.\u003c/p\u003e"},{"header":"5. RESULTS AND DISCUSSION","content":"\u003cp\u003e\u003cstrong\u003e5.1\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eINTRODUCTION\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe results chapter is not only a presentation of numbers, but also a reflection of how the structural system responds to different design choices. In this study, ETABS models were created for the same building, with the only variation being the position of the shear walls. The intention was to understand how changing the location of shear walls influences the seismic performance of the structure in terms of displacement, drift, and base shear.\u003c/p\u003e\n\u003cp\u003eShear walls are known to provide stiffness and strength to RC buildings, but their effectiveness greatly depends on their placement. A centrally located wall may improve symmetry, whereas walls at the periphery can increase lateral stiffness. Conversely, poorly placed or asymmetrically distributed walls may lead to torsional irregularities and undesirable response. Therefore, by modeling different configurations, the analysis aims to highlight not just which option performs best, but also why that configuration is superior.\u003c/p\u003e\n\u003cp\u003eIn this study, the same building was analyzed with different shear wall layouts. The results are compared in terms of roof displacement, inter-storey drift, and base shear. The following sections explain, step by step, how the analysis was carried out in ETABS, what results were obtained at each stage, and finally which model performed the best. This makes it clear how the final values were reached and why certain shear wall positions are more effective than others.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eModal Participating Mass Ratios\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cstrong\u003eTable: 5.1- Mode Shapes\u003c/strong\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eStructural\u0026nbsp;Wall System\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eMode\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003ePeriod (sec)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eUX\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eUY\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eRZ\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u0026nbsp;(1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e7.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e24%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e50%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e5.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e%0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e50%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e24%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e4.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e%83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u0026nbsp;(2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e5.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e73%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e5.15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e72%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e5%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e83%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u0026nbsp;(3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e4.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e18%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e75%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e4.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e74%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e15%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e2.53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e83%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u0026nbsp;(4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e4.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e6%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e63%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e4.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e63%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e3.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e76%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eStorey Displacement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDisplacement\u0026nbsp;due\u0026nbsp;to\u0026nbsp;Seismic Load\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cstrong\u003eTable:5.2- Storey Dispalcement due to Seismic Load\u003c/strong\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003eStructural\u0026nbsp;WallSystem\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003eMaximum\u003c/p\u003e\n \u003cp\u003eDisplacement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003eDisplacement\u0026nbsp;in\u0026nbsp;X\u003c/p\u003e\n \u003cp\u003edirection\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003eDisplacement\u0026nbsp;in\u0026nbsp;Y\u003c/p\u003e\n \u003cp\u003edirection\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e333.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e160.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e370.15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e333.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e231.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e420.36\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e333.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e150.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e350.37\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e333.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e148.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e325.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eDisplacement due to wind Load\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;Table:5.3- Displacement due to Wind Load\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003eStructural\u0026nbsp;WallSystem\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003eMaximum\u003c/p\u003e\n \u003cp\u003eDisplacement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003eDisplacement\u0026nbsp;in\u0026nbsp;X\u003c/p\u003e\n \u003cp\u003edirection\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003eDisplacement\u0026nbsp;in\u0026nbsp;Y\u003c/p\u003e\n \u003cp\u003edirection\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A (1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e166.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e120.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e330\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u0026nbsp;(2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e166.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e70\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e400.2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u0026nbsp;(3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e166.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e105.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e370.37\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u0026nbsp;(4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e166.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e338\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e5.2.3 Storey Drift\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;Table:5.4- Storey Drift\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 162px;\"\u003e\n \u003cp\u003eStructural\u0026nbsp;Wall\u0026nbsp;System\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003eMaximum\u0026nbsp;Drift\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003eDrift\u0026nbsp;in\u0026nbsp;X direction\u003c/p\u003e\n \u003cp\u003eSpec\u0026nbsp;X\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003eDrift\u0026nbsp;in\u0026nbsp;Y\u0026nbsp;direction\u003c/p\u003e\n \u003cp\u003eSpec\u0026nbsp;Y\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 162px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A (1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e1.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e1.03\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 162px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u0026nbsp;(2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e1.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e1.22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 162px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u0026nbsp;(3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e1.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 162px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u0026nbsp;(4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e1.03\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eFrom the analysis of all four ETABS models, it is clear that the position of shear walls has a significant impact on the structural response. Among the different configurations, \u003cstrong\u003ePlan A (4)\u0026nbsp;\u003c/strong\u003eshows the most favorable performance. The central placement of shear walls reduces overall roof displacement and keeps inter-storey drift within permissible limits. The mode shapes indicate a uniform distribution of stiffness, while torsional effects are minimal compared to the other layouts. Therefore, Plan A can be considered the most suitable arrangement, as it provides both structural efficiency and stability under seismic loading.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e5.2\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eTime Period\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn structural analysis, time period is the time taken by a building to travel through one complete cycle of vibration when it is acted upon by lateral forces like those caused by earthquakes or cyclonic winds in cyclonic areas. It is a critical parameter in the structural design and analysis of buildings, as it determines the natural frequency of the building, which in turn determines its resistance to external forces. The time period depends on many factors, such as the building\u0026apos;s height, weight, and stiffness, as well as the structural system employed in its construction. Through proper estimation of a building\u0026apos;s time period, architects and engineers can plan structures that are safer and more resistant to external forces, minimizing the chances of damage or collapse during earthquakes. Practically, a larger time period means smaller natural frequency, which means that the building will vibrate more slowly in response to outside forces.\u003c/p\u003e\n\u003cp\u003eOn the other hand, less time duration indicates a greater natural frequency, and hence oscillations are faster. Engineers utilize the time duration quite heavily in structural dynamics in determining the response of the building to dynamic loads and designing suitable measures for seismic vibration risk mitigation. The time duration determined from different structural systems through analysis using the software is listed below in a tabular form.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eModal\u0026nbsp;Participating\u0026nbsp;Mass Ratios\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003cstrong\u003eTable: 5.2.1- Mode Shapes\u003c/strong\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eStructural\u0026nbsp;Wall System\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eMode\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003ePeriod (sec)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eUX\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eUY\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003eRZ\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e4.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e6%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e63%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e4.68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e63%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e6%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e3.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e76%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" valign=\"top\" style=\"width: 180px;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003ePlan\u0026nbsp;B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e3.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e63%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e1%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e3.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e71%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e24%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 74px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 72px;\"\u003e\n \u003cp\u003e2.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e41%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eThe time period of the structural wall system is below 8 seconds is significant for several reasons as per IS 16700-2023, Clause 5.5.2, Page No 5. Firstly, it indicates that the structural system has a relatively high natural frequency, which means it can better resist lateral forces generated by earthquakes. This is because structures with higher natural frequencies are less likely to resonate with external forces and experience significant damage or collapse.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e5.2.2\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eStorey Displacement Displacement due to Seismic Load\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cstrong\u003eTable: 5.2.2 Displacement due to Seismic Load\u003c/strong\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003eStructural\u0026nbsp;WallSystem\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003eMaximum\u003c/p\u003e\n \u003cp\u003eDisplacement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003eDisplacement\u0026nbsp;in\u0026nbsp;X\u003c/p\u003e\n \u003cp\u003edirection\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003eDisplacement\u0026nbsp;in\u0026nbsp;Y\u003c/p\u003e\n \u003cp\u003edirection\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e333.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e148.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e325.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e333.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e231\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e193\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e5.2.3\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eDisplacement due to wind Load\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable:5.2.3- Displacement due to Wind load\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003eStructural\u0026nbsp;WallSystem\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003eMaximum\u003c/p\u003e\n \u003cp\u003eDisplacement\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003eDisplacement\u0026nbsp;in\u0026nbsp;X\u003c/p\u003e\n \u003cp\u003edirection\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003eDisplacement\u0026nbsp;in\u0026nbsp;Y\u003c/p\u003e\n \u003cp\u003edirection\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e166.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e338\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 161px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 125px;\"\u003e\n \u003cp\u003e166.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e119\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e155\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e5.2.4\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eStorey Drift\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable: 5.2.4- Storey Drift\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 162px;\"\u003e\n \u003cp\u003eStructural\u0026nbsp;Wall\u0026nbsp;System\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003eMaximum\u0026nbsp;Drift\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003eDrift\u0026nbsp;in\u0026nbsp;X direction\u003c/p\u003e\n \u003cp\u003eSpec\u0026nbsp;X\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003eDrift\u0026nbsp;in\u0026nbsp;Y\u0026nbsp;direction\u003c/p\u003e\n \u003cp\u003eSpec\u0026nbsp;Y\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 162px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;A\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e1.03\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 162px;\"\u003e\n \u003cp\u003ePlan\u0026nbsp;B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 124px;\"\u003e\n \u003cp\u003e1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 157px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 164px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"6. CONCLUSION","content":"\u003ch4\u003e5.1\u0026nbsp;Conclusion\u003c/h4\u003e\n\u003cp\u003eThe comparative dynamic performance analysis of \u003cstrong\u003ePlan A\u0026nbsp;\u003c/strong\u003e(horizontal regular) and \u003cstrong\u003ePlan B\u0026nbsp;\u003c/strong\u003e(horizontal\u0026nbsp;irregular,\u0026nbsp;unsymmetric)\u0026nbsp;was\u0026nbsp;conducted\u0026nbsp;for\u0026nbsp;a\u0026nbsp;G+28\u0026nbsp;reinforced\u0026nbsp;concrete\u0026nbsp;structural wall system located in \u003cstrong\u003eSeismic Zone V\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eBoth configurations meet the \u003cstrong\u003eIS 16700:2023, Clause 5.5.2\u0026nbsp;\u003c/strong\u003erequirement of having a fundamental\u0026nbsp;time\u0026nbsp;period\u0026nbsp;below\u0026nbsp;8\u0026nbsp;seconds,\u0026nbsp;indicating\u0026nbsp;higher\u0026nbsp;natural\u0026nbsp;frequencies\u0026nbsp;that minimize resonance risks during seismic events.\u003c/p\u003e\n\u003ch3\u003eModal\u0026nbsp;Participating\u0026nbsp;Mass\u0026nbsp;Ratios\u003c/h3\u003e\n\u003cp\u003e\u0026middot; \u003cstrong\u003ePlan B\u0026nbsp;\u003c/strong\u003eshows a strong concentration of modal mass participation in the primary modes, enabling efficient energy dissipation in both X and Y directions despite its asymmetry.\u003c/p\u003e\n\u003cp\u003e\u0026middot; \u003cstrong\u003ePlan\u0026nbsp;A\u0026nbsp;\u003c/strong\u003eexhibits more evenly distributed mode shapes, beneficial for balanced seismic response.\u003c/p\u003e\n\u003ch3\u003eStorey\u0026nbsp;Displacement\u003c/h3\u003e\n\u003cp\u003e\u0026middot; Under seismic loading, \u003cstrong\u003ePlan\u0026nbsp;B\u0026nbsp;\u003c/strong\u003erecords lower displacement in the Y-direction (193 mm) compared to Plan A (325.3 mm), indicating improved lateral stiffness in that axis.\u003c/p\u003e\n\u003cp\u003e\u0026middot; Under wind loading, \u003cstrong\u003ePlan B\u0026nbsp;\u003c/strong\u003eagain shows reduced displacement in the Y-direction (155 mm vs. 338 mm for Plan A), demonstrating better aerodynamic performance in one principal direction.\u003c/p\u003e\n\u003ch3\u003eStorey\u0026nbsp;Drift\u003c/h3\u003e\n\u003cp\u003e\u0026middot; Both plans satisfy the drift limitations of \u003cstrong\u003eIS 1893 (Part 1):2016\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003e\u0026middot; \u003cstrong\u003ePlan\u0026nbsp;B\u003c/strong\u003e\u0026rsquo;s drift distribution is slightly more localized but remains within permissible limits, suggesting potential for targeted strengthening rather than global modification.\u003c/p\u003e\n\u003ch4\u003eOverall\u0026nbsp;Observation\u003c/h4\u003e\n\u003cp\u003e\u0026middot; \u003cstrong\u003ePlan\u0026nbsp;B\u0026nbsp;\u003c/strong\u003eachieves competitive or superior performance in the Y-direction for both seismic and wind loads, showing that well-designed irregular layouts can still perform effectively in high seismic zones.\u003c/p\u003e\n\u003cp\u003e\u0026middot; \u003cstrong\u003ePlan A\u0026nbsp;\u003c/strong\u003emaintains more predictable and balanced performance across both axes, making it inherently simpler to design for uniform lateral response.\u003c/p\u003e\n\u003cp\u003eThe study confirms that while \u003cstrong\u003ePlan A\u0026nbsp;\u003c/strong\u003eoffers a balanced and predictable response, \u003cstrong\u003ePlan B\u0026nbsp;\u003c/strong\u003edemonstrates notable advantages in the Y-direction displacement and drift control under both seismic and wind loads. This shows that \u003cstrong\u003ehorizontal irregular structures\u003c/strong\u003e, if carefully engineered, can achieve performance levels close to or even surpassing regular configurations in specific parameters, provided torsional effects are effectively managed.\u003c/p\u003e"},{"header":"References","content":"\u003cp\u003e[B] Journal Papers\u003c/p\u003e\n\u003col\u003e\n \u003cli\u003eXing, B., Lumantarna, E., Lam, N. T. K., \u0026amp; Menegon, S. (2021). Torsional rigidity of asymmetrical multi-storey reinforced concrete buildings. \u003cem\u003eAustralian Earthquake Engineering Society Journal\u003c/em\u003e, November.\u003c/li\u003e\n \u003cli\u003eSwaliheen, M., \u0026amp; Bai, M. A. (2021). Comparison of analysis and design of regular and irregular configuration of multi story building in seismic zones. \u003cem\u003eInternational Journal for Research in Applied Science \u0026amp; Engineering Technology\u003c/em\u003e, August.\u003c/li\u003e\n \u003cli\u003eBotis, M. F., \u0026amp; Cerbu, C. (2020). A method for reducing of the overall torsion for reinforced concrete multi-storey irregular structures. \u003cem\u003eApplied Sciences\u003c/em\u003e, August. https://doi.org/10.3390/appXXXX\u003c/li\u003e\n \u003cli\u003eTodkar, O. M., \u0026amp; Salunke, P. J. (2019). Study of seismic response of multi-storied vertical irregular building due to stiffness irregularity. \u003cem\u003eInternational Journal of Research in Engineering, Science and Management\u003c/em\u003e, January.\u003c/li\u003e\n \u003cli\u003eIsmail, R., Mahmud, N. A., \u0026amp; Ishak, I. S. (2018). Seismic performance for vertical geometric irregularity frame structures. \u003cem\u003eIOP Conference Series: Earth and Environmental Science\u003c/em\u003e, 140(1), 012128. https://doi.org/10.1088/1755- 1315/140/1/012128\u003c/li\u003e\n \u003cli\u003eShelke, R. N., \u0026amp; Ansari, U. S. (2017). Seismic analysis of vertically irregular RCC building frames. \u003cem\u003eInternational Journal of Civil Engineering and Technology\u003c/em\u003e, January.\u003c/li\u003e\n \u003cli\u003eAhmed, M. M. M., Abdel Raheem, S. E., Ahmed, M. M., \u0026amp; Abdel-Shafy, A. G. A. (2016). Irregularity effects on the seismic performance of L-shaped multi-story buildings. \u003cem\u003eJournal of Engineering Sciences\u003c/em\u003e, September.\u003c/li\u003e\n \u003cli\u003eAbdel Naby, E. S., \u0026amp; Abou Khalifa, N. A. A. (2015). Comparison of analysis and design of regular and irregular configuration of multi story building in seismic zones. \u003cem\u003eJournal of Civil Engineering, United Arab Emirates University\u003c/em\u003e.\u003c/li\u003e\n \u003cli\u003eRana, D., \u0026amp; Raheem, J. (2015). Seismic analysis of regular \u0026amp; vertical geometric irregular RCC framed building. \u003cem\u003eInternational Research Journal of Engineering and Technology (IRJET)\u003c/em\u003e, July.\u003c/li\u003e\n \u003cli\u003eMonish, S., \u0026amp; Karuna, S. (2015). A study on seismic performance of high rise irregular RC framed buildings. \u003cem\u003eInternational Journal of Research in Engineering and Technology\u003c/em\u003e, May.\u003c/li\u003e\n \u003cli\u003eShaikh, A., \u0026amp; Deshmukh, G. (2013). Seismic response of vertical irregular RCC frame with irregularity at 4th floor. \u003cem\u003eInternational Journal of Emerging Technology and Advanced Engineering\u003c/em\u003e, August.\u003c/li\u003e\n \u003cli\u003eDoudoumis, N. I., \u0026amp; Gravalas, F. (2005). Effects of vertical irregularities on the seismic behaviour of multi-storey buildings with base isolation.\u0026nbsp;\u003cem\u003eResearch Gate\u003c/em\u003e, January.\u003cbr\u003e[C] Conference Papers\u003c/li\u003e\n \u003cli\u003ePatil, P. S., \u0026amp; Sonar, I. (2018, March). RCC structure with different bracing configuration on seismic issues. In \u003cem\u003eProceedings of the Civil Engineering Conference\u003c/em\u003e, ResearchGate.\u003c/li\u003e\n \u003cli\u003eKondekar, A. R., Dolare, D. B., Balande, P. V., Shinde, D. S., \u0026amp; Alkunte, A. J. (2022, May). Analysis \u0026amp; design of G+20 RCC building using X-bracing system with base isolator. \u003cem\u003eInternational Journal of Creative Research Thoughts\u003c/em\u003e.\u003c/li\u003e\n \u003cli\u003eChavan, R., \u0026amp; Sohoni, P. (2018). Seismic analysis of irregular RC structure with cross- bracing system.\u0026nbsp;\u003cem\u003eIJSRSET Conference Proceedings\u003c/em\u003e.\u003cbr\u003e[G] Standards \u0026amp; Codes\u003c/li\u003e\n \u003cli\u003eBureau of Indian Standards. (1987). \u003cem\u003eIS 875 (Part 2): Code of practice for design loads (other than earthquake) for buildings and structures \u0026ndash; Part 2: Imposed loads\u003c/em\u003e. New Delhi: BIS.\u003c/li\u003e\n \u003cli\u003eBureau of Indian Standards. (2000). \u003cem\u003eIS 456: Code of practice for plain and reinforced concrete\u003c/em\u003e. New Delhi: BIS.\u003c/li\u003e\n \u003cli\u003eBureau of Indian Standards. (2016). \u003cem\u003eIS 1893 (Part 1): Criteria for earthquake resistant design of structures\u003c/em\u003e. New Delhi: BIS\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":" Horizontal geometric irregularity, RC structures, torsional irregularity, reentrant corners, diaphragm discontinuity, seismic performance, IS 1893:2016, centre of mass, centre of rigidity, torsional stability, performance-based design, Indian seismic zones","lastPublishedDoi":"10.21203/rs.3.rs-7438879/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7438879/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe seismic performance of reinforced concrete (RC) structures is highly sensitive to their geometric configuration, both in plan and elevation. Among these, horizontal geometric irregularity— manifested in forms such as L-shaped, T-shaped, and Ushaped plans, re-entrant corners, diaphragm discontinuities, and torsional eccentricities—has been repeatedly identified as a major factor contributing to structural vulnerability during earthquakes. In India, where several regions fall under Seismic Zones III, IV, and V as per IS 1893:2016 (Part 1), the consequences of such irregularities can be severe if not addressed in the design stage. Irregular plan layouts alter the stiffness and mass distribution, often creating a mismatch between the centre of mass (CM) and centre of rigidity (CR). This results in significant torsional effects, stress concentrations, and non-uniform displacement patterns. Post-earthquake damage surveys, such as those following the 2001 Bhuj earthquake, have shown that irregular buildings suffered disproportionate damage compared to their regular counterparts. The current study aims to evaluate the seismic response of horizontally irregular RC buildings in compliance with Indian Standards, using analytical modelling and performance assessment techniques. By comparing regular and irregular configurations, the research seeks to provide practical recommendations for achieving torsional stability and improved seismic resilience.\u0026nbsp;\u003c/p\u003e","manuscriptTitle":"Effect of Horizontal Geometric Irregularity on a High Rise RC Structure","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-26 10:02:57","doi":"10.21203/rs.3.rs-7438879/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"5073a4a1-9152-4377-bb2c-f20cede1b8db","owner":[],"postedDate":"August 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":53599254,"name":"Civil Engineering"}],"tags":[],"updatedAt":"2025-08-26T10:02:58+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-26 10:02:57","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7438879","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7438879","identity":"rs-7438879","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}