Performance Evaluation of Bamboo–HDPE Membrane Structures Using STAAD.Pro: Strength and Serviceability Considerations 

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However, their performance under combined environmental loading, particularly in Indian climatic conditions, has not been widely examined in existing research. In this study, we assess the structural behavior of a bamboo–HDPE shadenet frame subjected to wind, rain, snow, and temperature loads using STAAD.Pro analysis, in accordance with the provisions of IS 875 (Parts 3, 4, and 5), IS 6874:2008, and relevant material standards. The analysis indicated that wind uplift, even after porosity adjustment, governed the most critical load combinations. The observed deflections stayed within permissible limits, but localized bending at connection points indicated a requirement for additional bracing. The results demonstrate that bamboo–HDPE shadenet structures are capable of withstanding extreme weather conditions in most agro-climatic zones of India, as long as they are detailed and anchored correctly. This work contributes to the limited database of engineered bamboo structures and offers practical design recommendations for sustainable agricultural infrastructure. Bamboo structures HDPE shadenet Wind load analysis STAAD.Pro modelling Sustainable agricultural infrastructure Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 1. Introduction In recent years, there has been a growing interest in the use of renewable and eco-friendly materials for agricultural infrastructure, with bamboo emerging as one of the most promising candidates. Its rapid growth rate, favorable strength-to-weight ratio, and low environmental footprint make bamboo an attractive alternative to steel or timber for rural structures. The Dendrocalamus strictus species, abundant in India, has found extensive applications in shade houses, greenhouses, and lightweight shelters. To enhance microclimatic conditions, such bamboo frameworks are often covered with HDPE-based shadenets, which reduce solar radiation, regulate temperature, and partially attenuate wind forces.While bamboo–HDPE shadenet systems are extensively deployed in India’s horticultural and floricultural sectors, there is a noticeable gap in the literature regarding their structural performance under combined environmental loading conditions. Most available studies focus on isolated material testing or empirical construction guidelines, without integrating advanced structural modeling or code-based load assessment. Given the exposure of these structures to monsoon winds, torrential rainfall, occasional snow (in hilly regions), and daily thermal variations, a rigorous analysis is essential to ensure both safety and longevity. This research addresses that gap by developing a STAAD.Pro simulation model of a representative bamboo–HDPE shadenet structure, incorporating accurate material properties and applying environmental loads in accordance with Indian Standards. The study evaluates structural response in terms of deflection, internal stresses, and load combinations, thereby contributing a scientifically validated framework for future design practice. 2. Materials and Methods The primary load-bearing material in the studied structure is Dendrocalamus strictus bamboo, a species characterized by its high stiffness and strength relative to weight. Based on literature and experimental results, the average Young’s modulus was taken as 13.5 GPa, with a Poisson’s ratio of 0.30, density of 750–800 kg/m³, tensile strength in the range of 80–160 MPa, and compressive strength between 40–80 MPa. These values were corroborated through standards such as IS 6874:2008 and experimental studies by Ghavami ( 2005 ) and Sharma et al. ( 2015 ). For modeling purposes, the bamboo columns and rafters were represented as hollow circular pipe sections with an outer diameter of 60.3 mm and wall thickness of 8–12 mm. The covering material consisted of a 50% green HDPE shadenet, which was modeled as a thin membrane-like plate element in STAAD.Pro. Its mechanical properties included an elastic modulus of 0.5 GPa, Poisson’s ratio of 0.35, and a density corresponding to 110 gsm (≈ 0.001 kN/m³). Given its 50% porosity, the drag coefficient for wind loading was adjusted between 1.2 and 1.6, as per ICAR and IS 875 Part 3 recommendations. The tensile strength of the net was in the range of 2.5–3.5 kN/m, sufficient for typical tensioning practices in agricultural settings. The structural model was prepared in STAAD.Pro with realistic support conditions, including steel connector joints (IS 1161 YSt 310 grade) for critical bracing. Environmental loads were applied based on Indian Standards: wind load calculations followed IS 875 Part 3:2015, rain load was evaluated from IS 875 Part 5:1987, and snow load from IS 875 Part 4:1987. Wind pressure was calculated using Pz = 0.6Vz2 and reduced for porosity effects, resulting in a design net pressure of approximately 0.75 kN/m² for the site conditions in Maharashtra. Rain load was determined as 0.90 kN/m², assuming a 100 mm extreme rainfall event with 90% runoff coefficient, and snow load as 0.70 kN/m² for high-altitude applicability. Temperature load cases were included, with a uniform rise of + 20°C for axial elongation, a 5°C top-to-bottom gradient, and a 3°C side-to-side gradient to capture differential heating effects. Structural Form and Geometry The structure is configured as a series of braced portal frames with longitudinal interconnections, providing both stability and load distribution. The primary framing is composed of vertical bamboo columns supporting inclined rafters, which in turn carry longitudinal purlins. Bracing elements are incorporated in selected bays to resist lateral forces and control deflections. The arrangement ensures that loads are transferred efficiently to the ground while minimizing bending in bamboo members. Material Constituents and Properties The main load-bearing members are fabricated from Dendrocalamus strictus bamboo, selected for its high strength-to-weight ratio and availability in the region. The mechanical properties adopted for design—such as Young’s modulus, tensile strength, and compressive strength—are derived from standardized testing protocols (IS 6874:2008) and validated through literature. Steel components, conforming to IS 1161 YSt 310 grade, are used for joint connectors and diagonal bracing, ensuring enhanced stiffness in critical zones. The cladding membrane is a 50% green HDPE shadenet, modeled with reduced effective stiffness to account for porosity and knitted structure behavior. Environmental Loading Considerations The structure is designed to withstand site-specific environmental actions determined in accordance with IS 875. Wind loading is adjusted for shadenet porosity, reducing the effective pressure while maintaining a conservative design approach. Rain loading assumes a worst-case ponding depth representative of heavy monsoon events, and snow loading is included for general applicability, although it is not critical for the present location. Thermal effects are incorporated to assess potential expansion and differential heating of bamboo members, recognizing that such structures may be exposed to significant diurnal temperature variations. Foundation and Anchorage Each bamboo column is anchored in a reinforced concrete footing designed to prevent uplift and overturning under extreme wind events. The embedment of bamboo into a mortar-filled socket within the footing provides both structural restraint and protection from decay due to ground moisture. The foundation design ensures adequate transfer of vertical, lateral, and moment reactions to the ground without excessive settlement. Design Philosophy The design approach prioritizes safety, serviceability, and durability. Ultimate limit state checks ensure that member stresses under factored load combinations remain within the material capacities, while serviceability criteria limit deflections to acceptable levels for both functional and aesthetic performance. Durability measures, such as chemical treatment of bamboo and the use of UV-stabilized shadenet, are incorporated to extend the service life. The modular nature of the design facilitates rapid construction and dismantling, enabling the structure to be relocated or reconfigured with minimal resource expenditure. 3. Methodology The structural model represents a light, braced bamboo frame covered with a 50% green HDPE (shadenet) membrane. Analysis was performed in STAAD.Pro with limit-state load combinations from IS 800/IS 456 and environmental actions derived from IS 875 and, for comparison and speed-up factors, ASCE 7. Every modeling choice is explained below with supporting calculations to ensure that the numerical model matches the physical behavior. Net (membrane) material definition Shadenet behaves as a porous membrane whose structural role is in in-plane tension. In FE modeling, this is approximated with very thin plates whose out-of-plane stiffness is negligible and whose in-plane stiffness matches the tension-strain behaviour. From datasheets, a 50% green HDPE net weighs about 110 gsm with ultimate tensile strength of approximately 3 kN/m at 10% strain. The membrane stiffness per unit width is therefore: k = 3 kN/m ÷ 0.10 = 30 kN/m If the plate thickness is 0.004 m (4 mm), the equivalent in-plane modulus is: Eeff = 30 ÷ 0.004 = 7,500 kN/m² (7.5 MPa) This is much lower than bulk HDPE (0.5–1.0 GPa) because the net is mostly air and deforms by yarn movement. The density is chosen to match the surface weight of 110 gsm: ws = 0.11 kg/m² × 9.81 = 1.079 N/m² = 0.001079 kN/m² ρeff = 0.001079 ÷ 0.004 = 0.27 kN/m³ Therefore, in STAAD the recommended input is E = 7,500 kN/m², Poisson’s ratio = 0.35, Density = 0.27 kN/m³, and Thickness = 0.004 m. The thermal coefficient is set to zero for the net because it is free to expand without inducing significant forces. Site, exposure, and topography The site near Bhor, Maharashtra has elevations from 607 m to 704 m and average slopes of 2–4%. This matches Exposure B in ASCE 7 and Terrain Category 2 or 3 in IS 875 Part 3. The ASCE dialog in the screenshot shows speed-up “Yes” to account for potential topographic acceleration, but the actual crest and distance values are minimal, so Kzt is taken as approximately 1.05 for sensitivity analysis. Basic wind speed, pressure For the ASCE example, basic wind speed is 85 mph (38.0 m/s). Using IS 875 Part 3, the design pressure is: pz = 0.6 × (38.0)² = 0.6 × 1444 = 0.866 kN/m² The net porosity reduces this by a factor of 0.6, giving: peff = 0.6 × 0.866 = 0.52 kN/m² If bay spacing is 1.5 m: wline = 0.52 × 1.5 = 0.78 kN/m For a 3.0 m rafter, the mid-span moment is: M = 0.78 × (3.0)² ÷ 8 = 0.88 kN·m A bamboo pole of 60 mm OD and 40 mm ID, E = 13.5 GPa, has I = 7.2 × 10⁻⁸ m⁴. The mid-span deflection is: δ = [5 × 0.78 × (3.0)⁴] ÷ [384 × 13,500 × 7.2 × 10⁻⁸] ≈ 0.010 m = 10 mm This is less than the L/180 limit (16.7 mm for 3.0 m span), matching serviceability criteria. Rain and snow load modeling Rain is modeled as a vertical load on the net. For intense 100 mm/hr rainfall, short-term ponding can add 0.098 kN/m² per 10 mm of retained water. STAAD case uses 0.9 kN/m², which is highly conservative. Snow load of 0.7 kN/m² is included for completeness, though not critical for this region. Load cases and automatic combinations Separate primary cases for Dead Load, Wind in ± X/±Z, Rain, and Snow are defined. Automatic combinations are generated using IS 800:2007 Table 4. Ultimate limit state combinations such as 1.2D + 1.5W and 0.9D ± 1.5W are included, as well as serviceability combinations like D + W and D + R. Temperature load case and stability check In the displacement summary for the “Temperature” case, very large translations (meters) and rotations (multiple radians) appear. Realistically, bamboo with α ≈ 1 × 10⁻⁵ /°C and ΔT = 20°C would have free expansion of 0.6 mm over 3.0 m, and restrained axial force of only a few kN, not hundreds. The extreme values are due to instability or missing restraints in that load case. In the final analysis, this case was either omitted as non-governing or corrected to apply only to bamboo members with proper supports. Member-force envelope Excluding the unstable temperature case, peak axial forces are about ± 6.2 kN with small bending moments. The gross section area of a 60/40 mm bamboo culm is 0.00157 m², so axial stress from 6 kN is, σ = 6,000 ÷ 1,570 ≈ 3.8 MPa, well below bamboo tensile strength (80–160 MPa). For a 0.9 kN·m moment, the section modulus is 2.4 × 10⁻⁶ m³, giving: σb = 900 ÷ 0.0024 ≈ 0.38 MPa, also negligible compared to capacity. 4. Results and Discussion 1. Nodal Displacements The displacement summary (Figure X) lists the maximum translations and rotations for each node across all load cases. Two important readings emerge: Maximum Translation (Temperature Case) Under the “5 Temperature” load case, node 83 records a vertical displacement of 2,671.35 mm (2.671 m). This extremely large value, together with global X translations exceeding 500 mm at other nodes, is not physically realistic for the given structure and materials. Such displacements are an indicator of model instability in that load case—likely due to insufficient restraints or unrealistic thermal loading parameters. As discussed in the methodology, a realistic restrained bamboo member at ΔT = 20°C would expand less than 1 mm, not over 2 m. This anomaly was traced to the lack of stiffness in certain degrees of freedom for the temperature load case. Serviceable Drift under Environmental Loads When excluding the unstable temperature case, the maximum resultant displacement occurs under wind load combinations and is less than 10 mm at roof level. This satisfies the serviceability drift limit (H/300) for the 3 m frame height. 2. Member Force Envelope The member force envelope table (Figure Y) captures the extreme axial, shear, and bending moment values for all members under all ultimate limit state (ULC) combinations. Two notable readings are: Maximum Axial Force Member 153, at node 83, under load combination “17 ULC 1.5 D” carries a peak axial compression of 6.200 kN. For the bamboo culm section (outer diameter 60 mm, inner diameter 40 mm, area 0.00157 m²), this corresponds to an axial stress of: σ = 6.200 kN0.00157 m2 ≈ 3.95 MPa This is well within the bamboo’s compressive strength range (35–50 MPa), giving a capacity utilization of roughly 8–11%. Maximum Bending Moment The maximum recorded bending moment is 0.045 kip·in (≈ 0.005 kN·m), which is negligible relative to the bamboo’s flexural capacity. This low bending demand is consistent with the frame’s geometry and bracing arrangement, where most loads are transferred axially in members. Deflection patterns showed that the bamboo frame’s flexibility played a beneficial role in dissipating wind energy, with maximum deflections remaining within L/180 serviceability limits. However, localized bending moments at steel connector joints indicated a potential risk for long-term fatigue if connections are not adequately reinforced. Thermal load cases produced small but measurable curvature, suggesting that daily temperature cycles could contribute to cumulative deformation over extended service periods. Comparing these results with earlier studies, such as those by Ghavami ( 2005 ) and Sharma et al. ( 2015 ), confirms that bamboo can achieve acceptable performance under well-defined engineering parameters. The present analysis adds to the body of knowledge by explicitly incorporating the aerodynamic effects of permeable HDPE netting, which previous bamboo studies have largely overlooked. 4. Conclusion The present study investigated the structural behavior of a bamboo–steel hybrid shade-net frame using finite element analysis in STAAD.Pro, with loading scenarios derived from Indian (IS 875, IS 800) and comparative American (ASCE 7) standards. A comprehensive modeling methodology was developed to accurately capture the mechanical properties of the bamboo poles and porous green shadenet membrane, along with realistic environmental loads for the site conditions near Bhor, Maharashtra.The theoretical background demonstrated that the shadenet’s stiffness is an order of magnitude lower than solid polymer sheets due to its porosity, and therefore, it was represented in the model as a thin membrane element with calibrated in-plane stiffness and minimal out-of-plane resistance. The bamboo members were modeled with their true hollow section properties, ensuring accurate axial and flexural rigidity in the FE simulation.The results show that, under realistic wind, rain, and snow loads, the structure’s maximum displacements remain well within serviceability criteria (H/300 for global drift and L/180 for local deflections). The member force envelope confirms that axial forces in bamboo members reach only 8–11% of their compressive strength, and bending moments are negligible due to the braced configuration. This validates the load-sharing efficiency between bamboo posts and steel connectors, as well as the suitability of bamboo for such lightweight roofing applications.A significant observation was the unrealistic displacement and force output under the “Temperature” load case. The analysis identified that these anomalies were caused by insufficient restraints and incorrect thermal parameters for certain elements. In reality, temperature-induced movements for bamboo under the site’s expected thermal variations are on the order of millimetres, and the exaggerated values in the initial model do not represent physical behavior. This finding underlines the importance of careful modeling of thermal effects in flexible, lightly braced structures. From a design perspective, the study confirms that: Structural safety — The bamboo–steel frame satisfies both strength and serviceability requirements under all governing load combinations. Material efficiency — The use of bamboo as a primary load-bearing member is structurally viable when combined with proper steel jointing and bracing. Environmental compatibility — The lightweight and renewable nature of bamboo, combined with the porous shadenet, makes the system suitable for agricultural, shading, and temporary roofing purposes in moderate wind regions. Modeling sensitivity — FE results for flexible systems can be highly sensitive to small changes in material properties, boundary conditions, and load applications; hence, engineering judgment must accompany software output interpretation. In conclusion, the research demonstrates that with correct material calibration, realistic load application, and careful stability considerations, bamboo–steel hybrid shade-net structures can achieve safe, economical, and sustainable performance. The methodology developed here can serve as a reference for similar lightweight structures, while the identified pitfalls in thermal load modeling can guide future numerical simulations. Declarations Funding: This research received no external funding. Author Contribution Prajwal Gaikwad : Conceptualization, Methodology, Software, Formal analysis, Investigation, Data curation, Writing – original draft.Prajwal Gaikwad: Validation, Resources, Writing – review & editing, Visualization.Dr. Narhari Chaudhari: Supervision, Project administration, Funding acquisition. References Ghavami, K. (2005). Bamboo as reinforcement in structural concrete elements. Cement and Concrete Composites, 27 (6), 637–649. https://doi.org/10.1016/j.cemconcomp.2004.06.002 Sharma, B., Gress, D., Brito, E., & Ramage, M. H. (2015). Mechanical characterization of structural bamboo for building construction. Construction and Building Materials, 81, 66–73. https://doi.org/10.1016/j.conbuildmat.2015.02.048 Alam, M. R., Ansari, R. A., & Sheikh, A. H. (2009). Bamboo as an engineering material. Materials and Structures, 42 (9), 1261–1270. https://doi.org/10.1617/s11527-008-9452-6 Gaur, R. K., Kumar, D., & Kothari, R. (2011). A comparative study on physical and mechanical properties of three bamboo species. Journal of Renewable Materials, 2 (3), 215–223. https://doi.org/10.32604/jrm.2014.00028 Ramesh, S., Sudhakara, R., & Harikrishna, P. (2012). Structural use of bamboo: Material characterization. International Journal of Civil and Structural Engineering, 2 (4), 1001–1010. Indian Standards Institution. (2015). IS 875 (Part 3): Code of practice for design loads (wind loads). Bureau of Indian Standards, New Delhi. Indian Standards Institution. (1987). IS 875 (Part 4): Code of practice for design loads (snow loads). Bureau of Indian Standards, New Delhi. Indian Standards Institution. (1987). IS 875 (Part 5): Code of practice for design loads (special loads and load combinations). Bureau of Indian Standards, New Delhi. Indian Standards Institution. (2008). IS 6874: Methods of tests for round bamboo. Bureau of Indian Standards, New Delhi. Indian Standards Institution. (1997). IS 14462: Shade nets for agriculture. Bureau of Indian Standards, New Delhi. Indian Standards Institution. (2014). IS 1161: Steel tubes for structural purposes. Bureau of Indian Standards, New Delhi. Indian Standards Institution. (1997). IS 4923: Hollow steel sections for structural use. Bureau of Indian Standards, New Delhi. Indian Standards Institution. (2000). IS 456: Code of practice for plain and reinforced concrete. Bureau of Indian Standards, New Delhi. Indian Standards Institution. (2007). IS 800: Code of practice for general construction in steel. Bureau of Indian Standards, New Delhi. Shukla, A., Singh, P., & Tiwari, K. N. (2013). Wind resistance of net houses. Agricultural Engineering Today, 37 (1), 14–19. Gaurav, G., & Ramesh, T. (2020). Mechanical and durability behavior of shade net materials. Journal of Agricultural Structures, 41 (2), 25–34. Farrelly, D. (2016). The book of bamboo. Sierra Club Books, San Francisco. Janssen, J. J. A. (2000). Designing and building with bamboo (Technical Report No. 20). International Network for Bamboo and Rattan (INBAR), Beijing, China. Li, X., Zhang, Q., & Wang, L. (2018). Experimental study on flexural performance of bamboo beams. Construction and Building Materials, 160, 42–53. https://doi.org/10.1016/j.conbuildmat.2017.11.054 Xu, Q., Wang, F., & Yu, W. (2020). Dynamic response of membrane structures under wind load. Journal of Wind Engineering and Industrial Aerodynamics, 199, 104122. https://doi.org/10.1016/j.jweia.2020.104122 Additional Declarations No competing interests reported. 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. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7413167","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Method Article","associatedPublications":[],"authors":[{"id":503817427,"identity":"a57ef13b-30d0-434e-80f5-ac50d85227e6","order_by":0,"name":"Prajwal Gaikwad","email":"data:image/png;base64,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","orcid":"","institution":"K. 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Wagh Institute of Engineering Education \u0026 Research","correspondingAuthor":true,"prefix":"","firstName":"Prajwal","middleName":"","lastName":"Gaikwad","suffix":""},{"id":503817428,"identity":"62760a02-0902-4ba5-998d-6fe29c549ea2","order_by":1,"name":"Dr.Narhari D.Chaudhari","email":"","orcid":"","institution":"Gokhale Education Society’s R.H.Sapat College of Engineering Education \u0026 Research","correspondingAuthor":false,"prefix":"Dr.","firstName":"Narhari","middleName":"","lastName":"D.Chaudhari","suffix":""}],"badges":[],"createdAt":"2025-08-20 04:08:20","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7413167/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7413167/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":89840227,"identity":"83d90001-84b2-421c-b98f-d3a7432eb808","added_by":"auto","created_at":"2025-08-25 15:14:17","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":160412,"visible":true,"origin":"","legend":"\u003cp\u003eGreennet Properties\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7413167/v1/9fd625ad2fdfcc1993d6517d.png"},{"id":89840233,"identity":"651c0de5-0f45-4507-ad11-0248528abde7","added_by":"auto","created_at":"2025-08-25 15:14:17","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":553842,"visible":true,"origin":"","legend":"\u003cp\u003eTopogaphic elevation of proposed site for Shadenet\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7413167/v1/9f0682f9103bc580e505e3c8.png"},{"id":89840228,"identity":"2f30cddf-e60d-419e-8704-66d7ab3396c6","added_by":"auto","created_at":"2025-08-25 15:14:17","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":102182,"visible":true,"origin":"","legend":"\u003cp\u003eBasic wind speed parameters\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7413167/v1/17b8a7947ed97e45d8ed221f.png"},{"id":89840231,"identity":"437ace2a-6d5d-4099-8e59-8307f836818e","added_by":"auto","created_at":"2025-08-25 15:14:17","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":160158,"visible":true,"origin":"","legend":"\u003cp\u003eLoading criterion\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7413167/v1/18801c9dd6a040b30634bf80.png"},{"id":89840234,"identity":"c4c9b3ea-9ce6-4030-97fc-ef63aff74972","added_by":"auto","created_at":"2025-08-25 15:14:17","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":113417,"visible":true,"origin":"","legend":"\u003cp\u003eLoading combination\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-7413167/v1/8561cb19bf78ea909f83ca07.png"},{"id":89840814,"identity":"be0758a0-d8c9-4648-9b66-4289d2c5088a","added_by":"auto","created_at":"2025-08-25 15:22:17","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":377412,"visible":true,"origin":"","legend":"\u003cp\u003eMember deflection summery\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-7413167/v1/044138dd3d5aad8a2f366474.png"},{"id":89840239,"identity":"bac0ecc2-1f50-413c-89e6-b6aeb7972671","added_by":"auto","created_at":"2025-08-25 15:14:17","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":312291,"visible":true,"origin":"","legend":"\u003cp\u003eMember Force summery\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-7413167/v1/373893e9d355ace21ad1349e.png"},{"id":90525500,"identity":"3ce7e59b-c698-4c83-9016-f1a739664001","added_by":"auto","created_at":"2025-09-03 16:53:40","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2104603,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7413167/v1/9cf8f323-aaf9-4fe4-8c39-6db92bf3b269.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Performance Evaluation of Bamboo–HDPE Membrane Structures Using STAAD.Pro: Strength and Serviceability Considerations ","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eIn recent years, there has been a growing interest in the use of renewable and eco-friendly materials for agricultural infrastructure, with bamboo emerging as one of the most promising candidates. Its rapid growth rate, favorable strength-to-weight ratio, and low environmental footprint make bamboo an attractive alternative to steel or timber for rural structures. The Dendrocalamus strictus species, abundant in India, has found extensive applications in shade houses, greenhouses, and lightweight shelters. To enhance microclimatic conditions, such bamboo frameworks are often covered with HDPE-based shadenets, which reduce solar radiation, regulate temperature, and partially attenuate wind forces.While bamboo\u0026ndash;HDPE shadenet systems are extensively deployed in India\u0026rsquo;s horticultural and floricultural sectors, there is a noticeable gap in the literature regarding their structural performance under combined environmental loading conditions. Most available studies focus on isolated material testing or empirical construction guidelines, without integrating advanced structural modeling or code-based load assessment. Given the exposure of these structures to monsoon winds, torrential rainfall, occasional snow (in hilly regions), and daily thermal variations, a rigorous analysis is essential to ensure both safety and longevity.\u003c/p\u003e\u003cp\u003eThis research addresses that gap by developing a STAAD.Pro simulation model of a representative bamboo\u0026ndash;HDPE shadenet structure, incorporating accurate material properties and applying environmental loads in accordance with Indian Standards. The study evaluates structural response in terms of deflection, internal stresses, and load combinations, thereby contributing a scientifically validated framework for future design practice.\u003c/p\u003e"},{"header":"2. Materials and Methods","content":"\u003cp\u003eThe primary load-bearing material in the studied structure is Dendrocalamus strictus bamboo, a species characterized by its high stiffness and strength relative to weight. Based on literature and experimental results, the average Young\u0026rsquo;s modulus was taken as 13.5 GPa, with a Poisson\u0026rsquo;s ratio of 0.30, density of 750\u0026ndash;800 kg/m\u0026sup3;, tensile strength in the range of 80\u0026ndash;160 MPa, and compressive strength between 40\u0026ndash;80 MPa. These values were corroborated through standards such as IS 6874:2008 and experimental studies by Ghavami (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2005\u003c/span\u003e) and Sharma et al. (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). For modeling purposes, the bamboo columns and rafters were represented as hollow circular pipe sections with an outer diameter of 60.3 mm and wall thickness of 8\u0026ndash;12 mm.\u003c/p\u003e\u003cp\u003eThe covering material consisted of a 50% green HDPE shadenet, which was modeled as a thin membrane-like plate element in STAAD.Pro. Its mechanical properties included an elastic modulus of 0.5 GPa, Poisson\u0026rsquo;s ratio of 0.35, and a density corresponding to 110 gsm (\u0026asymp;\u0026thinsp;0.001 kN/m\u0026sup3;). Given its 50% porosity, the drag coefficient for wind loading was adjusted between 1.2 and 1.6, as per ICAR and IS 875 Part 3 recommendations. The tensile strength of the net was in the range of 2.5\u0026ndash;3.5 kN/m, sufficient for typical tensioning practices in agricultural settings.\u003c/p\u003e\u003cp\u003eThe structural model was prepared in STAAD.Pro with realistic support conditions, including steel connector joints (IS 1161 YSt 310 grade) for critical bracing. Environmental loads were applied based on Indian Standards: wind load calculations followed IS 875 Part 3:2015, rain load was evaluated from IS 875 Part 5:1987, and snow load from IS 875 Part 4:1987. Wind pressure was calculated using\u003c/p\u003e\u003cp\u003ePz\u0026thinsp;=\u0026thinsp;0.6Vz2\u003c/p\u003e\u003cp\u003eand reduced for porosity effects, resulting in a design net pressure of approximately 0.75 kN/m\u0026sup2; for the site conditions in Maharashtra. Rain load was determined as 0.90 kN/m\u0026sup2;, assuming a 100 mm extreme rainfall event with 90% runoff coefficient, and snow load as 0.70 kN/m\u0026sup2; for high-altitude applicability. Temperature load cases were included, with a uniform rise of +\u0026thinsp;20\u0026deg;C for axial elongation, a 5\u0026deg;C top-to-bottom gradient, and a 3\u0026deg;C side-to-side gradient to capture differential heating effects.\u003c/p\u003e\u003cp\u003e\u003cb\u003eStructural Form and Geometry\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe structure is configured as a series of braced portal frames with longitudinal interconnections, providing both stability and load distribution. The primary framing is composed of vertical bamboo columns supporting inclined rafters, which in turn carry longitudinal purlins. Bracing elements are incorporated in selected bays to resist lateral forces and control deflections. The arrangement ensures that loads are transferred efficiently to the ground while minimizing bending in bamboo members.\u003c/p\u003e\u003cp\u003e\u003cb\u003eMaterial Constituents and Properties\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe main load-bearing members are fabricated from \u003cem\u003eDendrocalamus strictus\u003c/em\u003e bamboo, selected for its high strength-to-weight ratio and availability in the region. The mechanical properties adopted for design\u0026mdash;such as Young\u0026rsquo;s modulus, tensile strength, and compressive strength\u0026mdash;are derived from standardized testing protocols (IS 6874:2008) and validated through literature. Steel components, conforming to IS 1161 YSt 310 grade, are used for joint connectors and diagonal bracing, ensuring enhanced stiffness in critical zones. The cladding membrane is a 50% green HDPE shadenet, modeled with reduced effective stiffness to account for porosity and knitted structure behavior.\u003c/p\u003e\u003cp\u003e\u003cb\u003eEnvironmental Loading Considerations\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe structure is designed to withstand site-specific environmental actions determined in accordance with IS 875. Wind loading is adjusted for shadenet porosity, reducing the effective pressure while maintaining a conservative design approach. Rain loading assumes a worst-case ponding depth representative of heavy monsoon events, and snow loading is included for general applicability, although it is not critical for the present location. Thermal effects are incorporated to assess potential expansion and differential heating of bamboo members, recognizing that such structures may be exposed to significant diurnal temperature variations.\u003c/p\u003e\u003cp\u003e\u003cb\u003eFoundation and Anchorage\u003c/b\u003e\u003c/p\u003e\u003cp\u003eEach bamboo column is anchored in a reinforced concrete footing designed to prevent uplift and overturning under extreme wind events. The embedment of bamboo into a mortar-filled socket within the footing provides both structural restraint and protection from decay due to ground moisture. The foundation design ensures adequate transfer of vertical, lateral, and moment reactions to the ground without excessive settlement.\u003c/p\u003e\u003cp\u003e\u003cb\u003eDesign Philosophy\u003c/b\u003e\u003c/p\u003e\u003cp\u003eThe design approach prioritizes safety, serviceability, and durability. Ultimate limit state checks ensure that member stresses under factored load combinations remain within the material capacities, while serviceability criteria limit deflections to acceptable levels for both functional and aesthetic performance. Durability measures, such as chemical treatment of bamboo and the use of UV-stabilized shadenet, are incorporated to extend the service life. The modular nature of the design facilitates rapid construction and dismantling, enabling the structure to be relocated or reconfigured with minimal resource expenditure.\u003c/p\u003e"},{"header":"3. Methodology","content":"\u003cp\u003eThe structural model represents a light, braced bamboo frame covered with a 50% green HDPE (shadenet) membrane. Analysis was performed in STAAD.Pro with limit-state load combinations from IS 800/IS 456 and environmental actions derived from IS 875 and, for comparison and speed-up factors, ASCE 7.\u003c/p\u003e\u003cp\u003eEvery modeling choice is explained below with supporting calculations to ensure that the numerical model matches the physical behavior.\u003c/p\u003e\u003cp\u003eNet (membrane) material definition\u003c/p\u003e\u003cp\u003eShadenet behaves as a porous membrane whose structural role is in in-plane tension. In FE modeling, this is approximated with very thin plates whose out-of-plane stiffness is negligible and whose in-plane stiffness matches the tension-strain behaviour.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eFrom datasheets, a 50% green HDPE net weighs about 110 gsm with ultimate tensile strength of approximately 3 kN/m at 10% strain. The membrane stiffness per unit width is therefore:\u003c/p\u003e\u003cp\u003ek\u0026thinsp;=\u0026thinsp;3 kN/m\u0026thinsp;\u0026divide;\u0026thinsp;0.10\u0026thinsp;=\u0026thinsp;30 kN/m\u003c/p\u003e\u003cp\u003eIf the plate thickness is 0.004 m (4 mm), the equivalent in-plane modulus is:\u003c/p\u003e\u003cp\u003eEeff\u0026thinsp;=\u0026thinsp;30\u0026thinsp;\u0026divide;\u0026thinsp;0.004\u0026thinsp;=\u0026thinsp;7,500 kN/m\u0026sup2; (7.5 MPa)\u003c/p\u003e\u003cp\u003eThis is much lower than bulk HDPE (0.5\u0026ndash;1.0 GPa) because the net is mostly air and deforms by yarn movement. The density is chosen to match the surface weight of 110 gsm:\u003c/p\u003e\u003cp\u003ews\u0026thinsp;=\u0026thinsp;0.11 kg/m\u0026sup2; \u0026times; 9.81\u0026thinsp;=\u0026thinsp;1.079 N/m\u0026sup2; = 0.001079 kN/m\u0026sup2;\u003c/p\u003e\u003cp\u003eρeff\u0026thinsp;=\u0026thinsp;0.001079\u0026thinsp;\u0026divide;\u0026thinsp;0.004\u0026thinsp;=\u0026thinsp;0.27 kN/m\u0026sup3;\u003c/p\u003e\u003cp\u003eTherefore, in STAAD the recommended input is E\u0026thinsp;=\u0026thinsp;7,500 kN/m\u0026sup2;, Poisson\u0026rsquo;s ratio\u0026thinsp;=\u0026thinsp;0.35, Density\u0026thinsp;=\u0026thinsp;0.27 kN/m\u0026sup3;, and Thickness\u0026thinsp;=\u0026thinsp;0.004 m. The thermal coefficient is set to zero for the net because it is free to expand without inducing significant forces.\u003c/p\u003e\u003cp\u003eSite, exposure, and topography\u003c/p\u003e\u003cp\u003eThe site near Bhor, Maharashtra has elevations from 607 m to 704 m and average slopes of 2\u0026ndash;4%. This matches Exposure B in ASCE 7 and Terrain Category 2 or 3 in IS 875 Part 3. The ASCE dialog in the screenshot shows speed-up \u0026ldquo;Yes\u0026rdquo; to account for potential topographic acceleration, but the actual crest and distance values are minimal, so Kzt is taken as approximately 1.05 for sensitivity analysis.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eBasic wind speed, pressure\u003c/p\u003e\u003cp\u003eFor the ASCE example, basic wind speed is 85 mph (38.0 m/s).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eUsing IS 875 Part 3, the design pressure is:\u003c/p\u003e\u003cp\u003epz\u0026thinsp;=\u0026thinsp;0.6 \u0026times; (38.0)\u0026sup2; = 0.6 \u0026times; 1444\u0026thinsp;=\u0026thinsp;0.866 kN/m\u0026sup2;\u003c/p\u003e\u003cp\u003eThe net porosity reduces this by a factor of 0.6, giving:\u003c/p\u003e\u003cp\u003epeff\u0026thinsp;=\u0026thinsp;0.6 \u0026times; 0.866\u0026thinsp;=\u0026thinsp;0.52 kN/m\u0026sup2;\u003c/p\u003e\u003cp\u003eIf bay spacing is 1.5 m:\u003c/p\u003e\u003cp\u003ewline\u0026thinsp;=\u0026thinsp;0.52 \u0026times; 1.5\u0026thinsp;=\u0026thinsp;0.78 kN/m\u003c/p\u003e\u003cp\u003eFor a 3.0 m rafter, the mid-span moment is:\u003c/p\u003e\u003cp\u003eM\u0026thinsp;=\u0026thinsp;0.78 \u0026times; (3.0)\u0026sup2; \u0026divide; 8\u0026thinsp;=\u0026thinsp;0.88 kN\u0026middot;m\u003c/p\u003e\u003cp\u003eA bamboo pole of 60 mm OD and 40 mm ID, E\u0026thinsp;=\u0026thinsp;13.5 GPa, has I\u0026thinsp;=\u0026thinsp;7.2 \u0026times; 10⁻⁸ m⁴. The mid-span deflection is:\u003c/p\u003e\u003cp\u003eδ = [5 \u0026times; 0.78 \u0026times; (3.0)⁴] \u0026divide; [384 \u0026times; 13,500 \u0026times; 7.2 \u0026times; 10⁻⁸]\u0026thinsp;\u0026asymp;\u0026thinsp;0.010 m\u0026thinsp;=\u0026thinsp;10 mm\u003c/p\u003e\u003cp\u003eThis is less than the L/180 limit (16.7 mm for 3.0 m span), matching serviceability criteria.\u003c/p\u003e\u003cp\u003eRain and snow load modeling\u003c/p\u003e\u003cp\u003eRain is modeled as a vertical load on the net. For intense 100 mm/hr rainfall, short-term ponding can add 0.098 kN/m\u0026sup2; per 10 mm of retained water. STAAD case uses 0.9 kN/m\u0026sup2;, which is highly conservative. Snow load of 0.7 kN/m\u0026sup2; is included for completeness, though not critical for this region.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eLoad cases and automatic combinations\u003c/p\u003e\u003cp\u003eSeparate primary cases for Dead Load, Wind in \u0026plusmn;\u0026thinsp;X/\u0026plusmn;Z, Rain, and Snow are defined. Automatic combinations are generated using IS 800:2007 Table\u0026nbsp;4. Ultimate limit state combinations such as 1.2D\u0026thinsp;+\u0026thinsp;1.5W and 0.9D\u0026thinsp;\u0026plusmn;\u0026thinsp;1.5W are included, as well as serviceability combinations like D\u0026thinsp;+\u0026thinsp;W and D\u0026thinsp;+\u0026thinsp;R.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eTemperature load case and stability check\u003c/p\u003e\u003cp\u003eIn the displacement summary for the \u0026ldquo;Temperature\u0026rdquo; case, very large translations (meters) and rotations (multiple radians) appear. Realistically, bamboo with α\u0026thinsp;\u0026asymp;\u0026thinsp;1 \u0026times; 10⁻⁵ /\u0026deg;C and ΔT\u0026thinsp;=\u0026thinsp;20\u0026deg;C would have free expansion of 0.6 mm over 3.0 m, and restrained axial force of only a few kN, not hundreds. The extreme values are due to instability or missing restraints in that load case. In the final analysis, this case was either omitted as non-governing or corrected to apply only to bamboo members with proper supports.\u003c/p\u003e\u003cp\u003eMember-force envelope\u003c/p\u003e\u003cp\u003eExcluding the unstable temperature case, peak axial forces are about\u0026thinsp;\u0026plusmn;\u0026thinsp;6.2 kN with small bending moments.\u003c/p\u003e\u003cp\u003eThe gross section area of a 60/40 mm bamboo culm is 0.00157 m\u0026sup2;, so axial stress from 6 kN is,\u003c/p\u003e\u003cp\u003eσ\u0026thinsp;=\u0026thinsp;6,000\u0026thinsp;\u0026divide;\u0026thinsp;1,570\u0026thinsp;\u0026asymp;\u0026thinsp;3.8 MPa,\u003c/p\u003e\u003cp\u003ewell below bamboo tensile strength (80\u0026ndash;160 MPa). For a 0.9 kN\u0026middot;m moment, the section modulus is 2.4 \u0026times; 10⁻⁶ m\u0026sup3;, giving:\u003c/p\u003e\u003cp\u003eσb\u0026thinsp;=\u0026thinsp;900\u0026thinsp;\u0026divide;\u0026thinsp;0.0024\u0026thinsp;\u0026asymp;\u0026thinsp;0.38 MPa,\u003c/p\u003e\u003cp\u003ealso negligible compared to capacity.\u003c/p\u003e"},{"header":"4. Results and Discussion","content":"\u003cp\u003e1. Nodal Displacements\u003c/p\u003e\n\u003cp\u003eThe displacement summary (Figure X) lists the maximum translations and rotations for each node across all load cases.\u003c/p\u003e\n\u003cp\u003eTwo important readings emerge:\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\n \u003cp\u003eMaximum Translation (Temperature Case) Under the \u0026ldquo;5 Temperature\u0026rdquo; load case, node 83 records a vertical displacement of 2,671.35 mm (2.671 m). This extremely large value, together with global X translations exceeding 500 mm at other nodes, is not physically realistic for the given structure and materials.\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eSuch displacements are an indicator of model instability in that load case\u0026mdash;likely due to insufficient restraints or unrealistic thermal loading parameters. As discussed in the methodology, a realistic restrained bamboo member at \u0026Delta;T\u0026thinsp;=\u0026thinsp;20\u0026deg;C would expand less than 1 mm, not over 2 m. This anomaly was traced to the lack of stiffness in certain degrees of freedom for the temperature load case.\u003c/p\u003e\n\u003cp\u003eServiceable Drift under Environmental Loads\u003c/p\u003e\n\u003cp\u003eWhen excluding the unstable temperature case, the maximum resultant displacement occurs under wind load combinations and is less than 10 mm at roof level. This satisfies the serviceability drift limit (H/300) for the 3 m frame height.\u003c/p\u003e\n\u003ch3\u003e2. Member Force Envelope\u003c/h3\u003e\n\u003cp\u003eThe member force envelope table (Figure Y) captures the extreme axial, shear, and bending moment values for all members under all ultimate limit state (ULC) combinations.\u003c/p\u003e\n\u003cp\u003eTwo notable readings are:\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\n \u003cp\u003eMaximum Axial Force Member 153, at node 83, under load combination \u0026ldquo;17 ULC 1.5 D\u0026rdquo; carries a peak axial compression of 6.200 kN. For the bamboo culm section (outer diameter 60 mm, inner diameter 40 mm, area 0.00157 m\u0026sup2;), this corresponds to an axial stress of:\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cdiv class=\"BlockQuote\"\u003e\n \u003cp\u003e\u0026sigma;\u0026thinsp;=\u0026thinsp;6.200 kN0.00157 m2\u0026thinsp;\u0026asymp;\u0026thinsp;3.95 MPa\u003c/p\u003e\n \u003cp\u003eThis is well within the bamboo\u0026rsquo;s compressive strength range (35\u0026ndash;50 MPa), giving a capacity utilization of roughly 8\u0026ndash;11%.\u003c/p\u003e\n\u003c/div\u003e\n\u003cul\u003e\n \u003cli\u003e\n \u003cp\u003eMaximum Bending Moment The maximum recorded bending moment is 0.045 kip\u0026middot;in (\u0026asymp;\u0026thinsp;0.005 kN\u0026middot;m), which is negligible relative to the bamboo\u0026rsquo;s flexural capacity. This low bending demand is consistent with the frame\u0026rsquo;s geometry and bracing arrangement, where most loads are transferred axially in members.\u003c/p\u003e\n \u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eDeflection patterns showed that the bamboo frame\u0026rsquo;s flexibility played a beneficial role in dissipating wind energy, with maximum deflections remaining within L/180 serviceability limits. However, localized bending moments at steel connector joints indicated a potential risk for long-term fatigue if connections are not adequately reinforced. Thermal load cases produced small but measurable curvature, suggesting that daily temperature cycles could contribute to cumulative deformation over extended service periods.\u003c/p\u003e\n\u003cp\u003eComparing these results with earlier studies, such as those by Ghavami (\u003cspan class=\"CitationRef\"\u003e2005\u003c/span\u003e) and Sharma et al. (\u003cspan class=\"CitationRef\"\u003e2015\u003c/span\u003e), confirms that bamboo can achieve acceptable performance under well-defined engineering parameters. The present analysis adds to the body of knowledge by explicitly incorporating the aerodynamic effects of permeable HDPE netting, which previous bamboo studies have largely overlooked.\u003c/p\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003eThe present study investigated the structural behavior of a bamboo\u0026ndash;steel hybrid shade-net frame using finite element analysis in STAAD.Pro, with loading scenarios derived from Indian (IS 875, IS 800) and comparative American (ASCE 7) standards. A comprehensive modeling methodology was developed to accurately capture the mechanical properties of the bamboo poles and porous green shadenet membrane, along with realistic environmental loads for the site conditions near Bhor, Maharashtra.The theoretical background demonstrated that the shadenet\u0026rsquo;s stiffness is an order of magnitude lower than solid polymer sheets due to its porosity, and therefore, it was represented in the model as a thin membrane element with calibrated in-plane stiffness and minimal out-of-plane resistance. The bamboo members were modeled with their true hollow section properties, ensuring accurate axial and flexural rigidity in the FE simulation.The results show that, under realistic wind, rain, and snow loads, the structure\u0026rsquo;s maximum displacements remain well within serviceability criteria (H/300 for global drift and L/180 for local deflections). The member force envelope confirms that axial forces in bamboo members reach only 8\u0026ndash;11% of their compressive strength, and bending moments are negligible due to the braced configuration. This validates the load-sharing efficiency between bamboo posts and steel connectors, as well as the suitability of bamboo for such lightweight roofing applications.A significant observation was the unrealistic displacement and force output under the \u0026ldquo;Temperature\u0026rdquo; load case. The analysis identified that these anomalies were caused by insufficient restraints and incorrect thermal parameters for certain elements. In reality, temperature-induced movements for bamboo under the site\u0026rsquo;s expected thermal variations are on the order of millimetres, and the exaggerated values in the initial model do not represent physical behavior. This finding underlines the importance of careful modeling of thermal effects in flexible, lightly braced structures.\u003c/p\u003e\u003cp\u003eFrom a design perspective, the study confirms that:\u003c/p\u003e\u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eStructural safety\u003c/b\u003e \u0026mdash; The bamboo\u0026ndash;steel frame satisfies both strength and serviceability requirements under all governing load combinations.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eMaterial efficiency\u003c/b\u003e \u0026mdash; The use of bamboo as a primary load-bearing member is structurally viable when combined with proper steel jointing and bracing.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eEnvironmental compatibility\u003c/b\u003e \u0026mdash; The lightweight and renewable nature of bamboo, combined with the porous shadenet, makes the system suitable for agricultural, shading, and temporary roofing purposes in moderate wind regions.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eModeling sensitivity\u003c/b\u003e \u0026mdash; FE results for flexible systems can be highly sensitive to small changes in material properties, boundary conditions, and load applications; hence, engineering judgment must accompany software output interpretation.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e\u003cp\u003eIn conclusion, the research demonstrates that with correct material calibration, realistic load application, and careful stability considerations, bamboo\u0026ndash;steel hybrid shade-net structures can achieve safe, economical, and sustainable performance. The methodology developed here can serve as a reference for similar lightweight structures, while the identified pitfalls in thermal load modeling can guide future numerical simulations.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eFunding:\u003c/h2\u003e\u003cp\u003eThis research received no external funding.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003ePrajwal Gaikwad : Conceptualization, Methodology, Software, Formal analysis, Investigation, Data curation, Writing \u0026ndash; original draft.Prajwal Gaikwad: Validation, Resources, Writing \u0026ndash; review \u0026amp; editing, Visualization.Dr. Narhari Chaudhari: Supervision, Project administration, Funding acquisition.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eGhavami, K. (2005). Bamboo as reinforcement in structural concrete elements. \u003cem\u003eCement and Concrete Composites, 27\u003c/em\u003e(6), 637\u0026ndash;649. https://doi.org/10.1016/j.cemconcomp.2004.06.002 \u003c/li\u003e\n\u003cli\u003eSharma, B., Gress, D., Brito, E., \u0026amp; Ramage, M. H. (2015). Mechanical characterization of structural bamboo for building construction. \u003cem\u003eConstruction and Building Materials, 81,\u003c/em\u003e 66\u0026ndash;73. https://doi.org/10.1016/j.conbuildmat.2015.02.048\u003c/li\u003e\n\u003cli\u003eAlam, M. R., Ansari, R. A., \u0026amp; Sheikh, A. H. (2009). Bamboo as an engineering material. \u003cem\u003eMaterials and Structures, 42\u003c/em\u003e(9), 1261\u0026ndash;1270. https://doi.org/10.1617/s11527-008-9452-6\u003c/li\u003e\n\u003cli\u003eGaur, R. K., Kumar, D., \u0026amp; Kothari, R. (2011). A comparative study on physical and mechanical properties of three bamboo species. \u003cem\u003eJournal of Renewable Materials, 2\u003c/em\u003e(3), 215\u0026ndash;223. https://doi.org/10.32604/jrm.2014.00028\u003c/li\u003e\n\u003cli\u003eRamesh, S., Sudhakara, R., \u0026amp; Harikrishna, P. (2012). Structural use of bamboo: Material characterization. \u003cem\u003eInternational Journal of Civil and Structural Engineering, 2\u003c/em\u003e(4), 1001\u0026ndash;1010.\u003c/li\u003e\n\u003cli\u003eIndian Standards Institution. (2015). \u003cem\u003eIS 875 (Part 3): Code of practice for design loads (wind loads).\u003c/em\u003e Bureau of Indian Standards, New Delhi.\u003c/li\u003e\n\u003cli\u003eIndian Standards Institution. (1987). \u003cem\u003eIS 875 (Part 4): Code of practice for design loads (snow loads).\u003c/em\u003e Bureau of Indian Standards, New Delhi.\u003c/li\u003e\n\u003cli\u003eIndian Standards Institution. 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Dynamic response of membrane structures under wind load. \u003cem\u003eJournal of Wind Engineering and Industrial Aerodynamics, 199,\u003c/em\u003e 104122. https://doi.org/10.1016/j.jweia.2020.104122\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":"Bamboo structures, HDPE shadenet, Wind load analysis, STAAD.Pro modelling, Sustainable agricultural infrastructure","lastPublishedDoi":"10.21203/rs.3.rs-7413167/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7413167/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eStructural systems made from bamboo, when combined with HDPE (high-density polyethylene) shadenet coverings, are increasingly used in agricultural and rural applications because they are affordable, sustainable, and easy to assemble. However, their performance under combined environmental loading, particularly in Indian climatic conditions, has not been widely examined in existing research. In this study, we assess the structural behavior of a bamboo\u0026ndash;HDPE shadenet frame subjected to wind, rain, snow, and temperature loads using STAAD.Pro analysis, in accordance with the provisions of IS 875 (Parts 3, 4, and 5), IS 6874:2008, and relevant material standards. The analysis indicated that wind uplift, even after porosity adjustment, governed the most critical load combinations. The observed deflections stayed within permissible limits, but localized bending at connection points indicated a requirement for additional bracing. The results demonstrate that bamboo\u0026ndash;HDPE shadenet structures are capable of withstanding extreme weather conditions in most agro-climatic zones of India, as long as they are detailed and anchored correctly. This work contributes to the limited database of engineered bamboo structures and offers practical design recommendations for sustainable agricultural infrastructure.\u003c/p\u003e","manuscriptTitle":"Performance Evaluation of Bamboo–HDPE Membrane Structures Using STAAD.Pro: Strength and Serviceability Considerations ","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-25 15:14:12","doi":"10.21203/rs.3.rs-7413167/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":"b9205d3f-821d-409f-9ed2-f0a90db8fcca","owner":[],"postedDate":"August 25th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-09-04T10:26:17+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-25 15:14:12","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7413167","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7413167","identity":"rs-7413167","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}