Comparative Study of Self-Curing Concrete Using Lightweight Aggregates and Hydrogel (SAP) as Internal Curing Agents

Comparative Study of Self-Curing Concrete Using Lightweight Aggregates and Hydrogel (SAP) as Internal Curing Agents | 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 Comparative Study of Self-Curing Concrete Using Lightweight Aggregates and Hydrogel (SAP) as Internal Curing Agents Parul Mangal, Jayesh Juremalani This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9186403/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 4 You are reading this latest preprint version Abstract Self-curing concrete, also known as internal curing concrete, has been developed to overcome the limitations of conventional external curing, particularly in situations involving water scarcity and inadequate curing conditions. In this study, M45 grade concrete incorporating two internal curing systems—(i) 50% lightweight aggregate (LWA) replacement combined with 2.5% polyethylene glycol (PEG-400), and (ii) 0.2% superabsorbent polymer (SAP) by weight of cement—was experimentally investigated. The performance of these mixes was evaluated through workability, compressive strength, split tensile strength, and scanning electron microscopy (SEM) tests conducted at curing ages of 7, 14, and 28 days. The results indicated that although both self-curing systems exhibited reduced workability compared to conventional concrete, they achieved a significant improvement in compressive strength of approximately 15–20% at 28 days. SAP-based concrete showed enhanced split tensile strength, while the LWA + PEG system exhibited a marginal reduction. SEM analysis further confirmed improved hydration and microstructural densification due to the sustained internal moisture supply. Overall, the findings demonstrate that self-curing concrete, particularly when incorporating SAP, offers a viable and effective solution for improving strength and durability in conditions where conventional curing practices are difficult to implement. Self-curing Light weight aggregates Hydrogel Cement SAP Compressive strength Workability Split tensile strength Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Introduction As we all know concrete is the most widely used construction material out of other materials, its all because of its great strength, durability and versatility of being moulded into various shapes. However, it has been noticed that the performance and longevity of concrete structures depends highly on the proper curing of the hardened concrete, which ensures the development of different mechanical properties by proper hydration of cement. Normally traditional curing methods such as water ponding, membrane curing, heat application etc. have been adopted in almost all places. But it is not feasible to use traditional curing of concrete in places like vertical structures or where there is scarcity of water. However, if insufficient curing can lead to incomplete hydration process which will result in reduction in strength and increasing permeability of concrete which in turn results in early-age cracking. Therefore, proper curing is very essential for complete hydration of concrete. Concrete durability and performance strongly depend on proper curing. Inadequate curing results in incomplete hydration, reduced strength, and higher permeability. Internal curing using lightweight aggregates and superabsorbent polymers has been proven effective in enhancing hydration and reducing shrinkage [ 1 – 6 ]. This study evaluates the comparative performance of LWA + PEG and SAP-based self-curing systems in high-strength concrete. To address the challenges faced during traditional curing of concrete, the concept of self-curing or internal curing has been developed as an innovative solution. Self-curing concrete is the one which has the capability to retains moisture within and releases it whenever required for hydration process, which reduces the usage of traditional curing methods. This mechanism of retaining moisture internal can be achieved by adding certain internal curing agents such as Light Weight Aggregates, Super Absorbent Polymers, Polyethylene Glycol, Wat er Soluble Polymers, Natural or Synthetic Fibers etc. These agents can absorb a lot of water within and enhance the hydration process by releasing water whenever required. They can absorb the moisture either from concrete or from the atmosphere. This method of internal curing is one of the best practices for sustainable concrete which saves a lot of water. Among the various approaches for self-curing concrete, usage of Light Weight Aggregates (LWA) and Super Absorbent Polymers (SAP) have gained an attention in the present research due to its effectiveness in improving hydration, reducing shrinkage and enhancing overall performance of concrete. Poly Ethylene Glycol (PEG-400) also played an important role as a self-curing agent in the present research as it is a water-soluble polymer which has an ability to retain moisture. The present research aims to investigate the comparative performance of M45 grade self-curing concrete using two internal curing systems: a combination of 50% LWA and 2.5% PEG-400, and 0.2% SAP (hydrogel), each dosed by the weight of cement. The study evaluates key mechanical properties, including workability, compressive strength, and split tensile strength at 7, 14, and 28 days, and compares the results with those of conventionally cured concrete. This research provides insights into the effectiveness of different self-curing agents in enhancing the mechanical performance of high-strength concrete, with implications for sustainable and durable construction practices [ 3 , 4 , 6 ]. Materials & Methods Ordinary Portland Cement (OPC 53 grade), natural river sand, crushed coarse aggregates, lightweight aggregates, PEG-400, and hydrogel (SAP) were used. Material properties are summarized in Table 1 . Mix proportions are given in Table 2 , and test methods are listed in Table 3 . The materials used in the present investigations are as follows: 1. Cement – OPC 53 grade cement has been used with 3.15 specific gravity. Various physical and chemical tests have been conducted as per Indian Standard codes. The various physical properties have been shown in Table 1 below: 2. Aggregates - The fine aggregate used was natural river sand as per IS:383. The specific gravity of sand is found to be 2.626 and fineness modulus obtained is 3.11. The coarse aggregate used in the present research was having 20 mm nominal size. The grain size analysis has been shown in Fig. 1 & Fig. 2 below. Table 1 Physical properties of Cement [ 21 , 22 , 23 , 24 , 25 ] Sr. No. Type of Test Method of Test Test Result Limits as per IS: 269: 2020 OPC 53 Grade 1 Consistency (%) IS: 4031 Part 4: 1988 RA 2019 28.50 - 2 Setting Time IS: 4031 Part 5: 1988 RA 2019 a Initial Setting Time, min Clause 5.2 135 Shall not be 600 Minutes 3 Soundness, Le'chatelier, mm IS: 4031 Part 3: 1988 RA 2019 1.06 Expansion Shall be < 10mm 4 Fineness by Blain Air Permeability, M 2 /kg IS: 4031 Part 2: 1988 RA 2019 284.72 Shall not be less than 225 m 2 /kg 5 Compressive Strength, N/mm 2 a 72 ± 1 h, Strength IS: 4031 Part 6: 1988 RA 2019 30.90 Shall not be < 27 N/mm 2 b 168 ± 2 h, Strength 42.10 Shall not be < 37 N/mm 2 c 672 ± 4 h, Strength 56.18 Shall not be < 53 N/mm 2 3. Water – Normal tap water has been used for the present research. 4. Light Weight Aggregates – LWA used in this present research has been purchased from Shri Goverdhan Quarry Works, Pavagadh, Vadodara of nominal size 20 mm with proportion of 50% as a replacement of coarse aggregates having specific gravity 2.838. The grain size analysis has been shown in Fig. 3 below. 5. Poly Ethylene Glycol – In the present research Polyethylene Glycol-400 (PEG-400) with a proportion of 2.5% by the weight of cement has been used which is a water-soluble polymer widely used as an internal curing (self-curing) agent in concrete. Its primary function is to retain moisture within the concrete matrix, ensuring continuous hydration of cement, especially where external curing is challenging or water resources are limited. 6. Super Absorbent Polymers – Hydrogel has been used as SAP − 0.2% by the weight of cement. They are synthetic hydrogels used as internal curing agents in concrete to retain moisture, improve hydration, and mitigate shrinkage. Their water-absorbing capacity (up to 500 times their weight) makes them effective for enhancing durability and mechanical performance in low water-to-cement (w/c) ratio concretes. Mix Proportions In this study three mix proportions have been casted which has been shown below: Control Mix : Conventional concrete with water curing LWA Mix : 50% replacement of coarse aggregate with LWA SAP Mix : 0.2% SAP by weight of cement Table 2 Mix ID S.No. Mix Mix ID 1 Control Mix M1 2 LWA Mix M2–50% LWA + 2.5% weight of cement (PEG) 3 SAP Mix M3–0.2% Hydrogel by weight of cement Tests Performed Various tests performed have been performed as per specified IS Code and has been tabulated below in Table 3 : Table 3 Tests Performed Sr. No. Property Tests IS Code 1 Fresh Workability IS: 1199–2018 (2) 2 Hardened Compressive strength test IS: 456–2000 Split tensile strength test IS :5816 − 1959 Scanning electron microscope - Results & Discussions Workability The workability is the fresh concrete property which has been done by using Slump cone test. It has been done for all mix proportions of concrete i.e. conventional concrete, concrete with replacement of aggregates with light weight aggregates and concrete with hydrogel as an addition by the weight of cement. It has been observed that workability decreases for both mixes M2 and M3 as compared to conventional concrete. Workability results obtained using the slump cone test are presented in Table 4 and illustrated in Fig. 6 . Table 4 Workability S.No. Mix Workability 1 M1 140 mm 2 M2 30 mm 3 M3 130 mm Compressive Strength It is one of the hardened concrete properties to check the strength of concrete for specific grade by using Compression Testing Machine (CTM). Cube specimen of size 150 x 150 x 150 mm has been casted and cured for 7, 14 and 28 days and tested for compressive strength. Three specimens have been casted out of which one has been cured conventionally and other two has been self-curing by using self-curing agents i.e. LWA with PEG-400 and Hydrogel. Results showed that self-cured concrete shows better strength as compared to conventional concrete. It has been observed that after 28 days of self-curing there is approximately 15% increase in compressive strength. Compressive strength results for all mixes are shown in Table 5 and Fig. 7 . Table 5 Compressive Strength S.No. Mix Compressive Strength, N/mm 2 7 days 14 days 28 days 1 M1 41.22 44.62 46.69 2 M2 39.36 44.54 54 3 M3 43.61 51 53.78 Split Tensile Strength This test measures the tensile strength of concrete which has the ability to withstand tensile stress of concrete to check the hardened property of concrete. In this test cylindrical specimen of size 150 mm x 300 mm has been used to check the tensile property of self-cured concrete after curing of 7, 14 and 28 days. In the present research, it has been observed that split tensile strength has been decreased for self-cured concrete with LWA + PEG but increases for SAP cured concrete as compared to conventionally cured concrete. Results showed that tensile strength for LWA + PEG self-curing agent has been decreased by 28% approximately, whereas for SAP as self-curing agent tensile strength has been increased by approximately 24%. Split tensile strength results are summarized in Table 6 and Fig. 8 . Table 6 Split Tensile Strength S.No. Mix Split Tensile Strength, N/mm 2 7 days 14 days 28 days 1 M1 1.95 3.79 4.66 2 M2 2.08 3.16 3.31 3 M3 2.51 4.99 5.20 Discussions The reduction in workability observed in self-curing mixes is attributed to water absorption by LWA and SAP. The improved compressive strength is due to continuous internal water supply, enhancing hydration. SAP showed superior tensile performance due to better pore refinement, as supported by SEM observations (Figs. 9 and 10). Conclusion This research effectively compares the different mechanical properties i.e. workability, compressive strength and split tensile strength of M45 grade for conventional concrete, light weight aggregate concrete with PEG-400 and hydrogel enhanced concrete. Also, comparative analysis of microstructure has been done by using Scanning Electron Microscope test. The results so obtained by conducting different tests have been summarized below: Workability for conventional concrete was found to be 140 mm which is approximately 78% higher than the workability obtained for light weight aggregate concrete in which LWA and PEG was used as self-curing agents, whereas for hydrogel enhanced concrete was approximately 7% lower than the workability obtained for conventional concrete. Compressive strength test revealed that all the three mixes i.e. M1, M2 & M3 were meeting all the requirements required for compressive strength as for M45 grade concrete compressive strength should be 45 N/mm 2 at 28 days. The results thus obtained shows that there was increase in strength of 3.7%, 20% and 19.5% for M1, M2 & M3 respectively. Split tensile strength results shows that for concrete mix containing hydrogel as self-curing agent has maximum tensile strength but for concrete mix having light weight aggregates with PEG-400 does not meet the requirements of minimum tensile strength which is 29% lower than nominal strength after 28 days of curing. Finally, SEM analysis shows the valuable information in which different microstructural properties of concrete mixes have been identified, which demonstrates how different self-curing agents influences the internal structure of concrete mixes. The SEM photographs show the variation in particles count and arrangement in different samples. The study concludes that self-curing concrete significantly enhances compressive strength and microstructural quality. SAP-based self-curing exhibited balanced performance in both compressive and tensile strength, making it a promising solution for sustainable construction. Overall, it has been concluded that by adding different self-curing agents in different concrete mixes of M45 grade, there was optimal increase in the different mechanical properties of concrete but certain aspects can be found in future for increasing the workability of concrete. Further research can be done for the selection and evaluation of the different curing agents which are necessary to achieve performance enhancement. Declarations Author Contribution Parul Mangal: Conceptualization, methodology, investigation, experimental work, Data curation, Formal analysis, visualization, and Writing – original draft preparation.Dr. Jayesh Juremalani: Supervision, validation, methodology refinement, resources, review & editing, project administration, and guidance in interpretation of results and manuscript improvement.All authors have read and approved the final manuscript and agree to be accountable for all aspects of the work. Acknowledgement I want to express my sincere gratitude to everyone who helped me in conducting this research which involves lightweight aggregates, PEG-400 and hydrogel as self-curing agents. I particularly thank my guide Dr. Jayesh Juremalani under his guidance and expertise research was conducted in proper manner and sequentially. I would also like to appreciate my faculty members and laboratory staff for their help in collecting data and conducting experimental work. I am also grateful for the Micro-Nano R&D Center at Parul University for conducting the Scanning Electron Microscope analysis for the different concrete samples after 28 days of self-curing. Furthermore, I want to express my gratitude for utilizing the resources and facilities provided by the GES Lab, Khodiyar Nagar, Vadodara as they helped a lot in completing the research successfully. Lastly, I am truly thankful to my family and friends for their constant encouragement and understanding during this journey. Their support has been crucial in helping me achieve my goals. References Hamzah N, Saman M, Baghban H, Sam MHM, Faridmehr AR, Muhd Sidek I, Huseien MN, G. F. A review on the use of self-curing agents and its mechanism in high-performance cementitious materials. Buildings. 2022;12(2):152. Nduka DO, Ameh JO, Joshua O, Ojelabi R. Awareness and benefits of self-curing concrete in construction projects: builders and civil engineers’ perceptions. Buildings. 2018;8(8):109. 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Evaluation of Calotropis gigantea as a promising raw material for fiber-reinforced composite. J Compos Mater. 2009;43(11):1297–304. IS. 4031 (2) – 1999 Determination of Fineness by Blaine Air Permeability Method. IS. 4031 (3) – 1988 Determination of Soundness of Cement. IS. 4031 (4) – 1988 Determination of Consistency of Standard Cement Paste. IS. 4031 (5) – 1988 Determination of Initial and Final Setting Times of Cement. IS. 4031 (6) – 1988 Determination of Compressive Strength of Cement. IS. 4031 (11) – 1988 Determination of Density. IS. 2720 (3) – 1980 Methods of Test for Soils - Determination of Specific Gravity. IS 269. 2015 – Ordinary Portland Cement – Specification. IS. 383:1970 – Specification for Coarse and Fine Aggregates from Natural Sources for Concrete. IS. 2386 (1) – 1963 Methods of Test for Aggregates for Concrete - Particle Size and Shape. IS. 2386 (3) – 1963 Methods of Test for Aggregates for Concrete - Specific Gravity, Density, Voids ‘, Absorption and Bulking. IS. 2386 (4) – 1963 Methods of Test for Aggregates for Concrete - Mechanical Properties. IS 3025. (11) – 1983 Methods of Sampling and Test (Physical and Chemical) For Water and Waste Water - pH Value. IS 3025. (17) – 1984 Methods of Sampling and Test (Physical and Chemical) For Water and Waste Water - Non-filterable Residue (Total Suspended Solids). IS 3025. (18) – 1984 Methods of Sampling and Test (Physical and Chemical) For Water and Wastewater - Volatile and Fixed Residue (Total, Filterable and Non-filterable). IS 3025. (32) – 1988 Methods of Sampling and Test (Physical and Chemical) For Water and Wastewater - Chloride. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 28 Mar, 2026 Editor assigned by journal 24 Mar, 2026 Submission checks completed at journal 24 Mar, 2026 First submitted to journal 21 Mar, 2026 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-9186403","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":610764524,"identity":"c134304f-01cb-4970-b22d-2713f0a5c652","order_by":0,"name":"Parul 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7","display":"","copyAsset":false,"role":"figure","size":33296,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eCompressive Strength\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-9186403/v1/2602707df0ff28d7f30c4b61.png"},{"id":105267024,"identity":"1ded2872-083b-4274-bf7b-a6fa89cf750a","added_by":"auto","created_at":"2026-03-24 07:44:58","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":35700,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSplit Tensile Strength\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-9186403/v1/443928b6fd7da74b6aabbefc.png"},{"id":105564486,"identity":"7bf29a2e-d2de-41e1-a3d4-ba8098b73777","added_by":"auto","created_at":"2026-03-27 12:49:44","extension":"jpg","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":92182,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSEM image 0.2% Hydrogel\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"9.jpg","url":"https://assets-eu.researchsquare.com/files/rs-9186403/v1/dfabfdaf0446c858f3b325a2.jpg"},{"id":105564538,"identity":"709a8917-0d3c-484c-a257-d3b169b82e9a","added_by":"auto","created_at":"2026-03-27 12:49:55","extension":"png","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":389107,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSEM image LWA + PEG-400\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"10.png","url":"https://assets-eu.researchsquare.com/files/rs-9186403/v1/f4b250b931f5dc3e6bc2db9f.png"},{"id":105568852,"identity":"5999bee3-69d3-4db7-861c-3c1c99455c33","added_by":"auto","created_at":"2026-03-27 13:10:33","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1415579,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9186403/v1/94e42d5a-65db-4264-aac1-565e7416172a.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Comparative Study of Self-Curing Concrete Using Lightweight Aggregates and Hydrogel (SAP) as Internal Curing Agents","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAs we all know concrete is the most widely used construction material out of other materials, its all because of its great strength, durability and versatility of being moulded into various shapes. However, it has been noticed that the performance and longevity of concrete structures depends highly on the proper curing of the hardened concrete, which ensures the development of different mechanical properties by proper hydration of cement. Normally traditional curing methods such as water ponding, membrane curing, heat application etc. have been adopted in almost all places. But it is not feasible to use traditional curing of concrete in places like vertical structures or where there is scarcity of water. However, if insufficient curing can lead to incomplete hydration process which will result in reduction in strength and increasing permeability of concrete which in turn results in early-age cracking. Therefore, proper curing is very essential for complete hydration of concrete.\u003c/p\u003e \u003cp\u003eConcrete durability and performance strongly depend on proper curing. Inadequate curing results in incomplete hydration, reduced strength, and higher permeability. Internal curing using lightweight aggregates and superabsorbent polymers has been proven effective in enhancing hydration and reducing shrinkage [\u003cspan additionalcitationids=\"CR2 CR3 CR4 CR5\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. This study evaluates the comparative performance of LWA\u0026thinsp;+\u0026thinsp;PEG and SAP-based self-curing systems in high-strength concrete.\u003c/p\u003e \u003cp\u003eTo address the challenges faced during traditional curing of concrete, the concept of self-curing or internal curing has been developed as an innovative solution. Self-curing concrete is the one which has the capability to retains moisture within and releases it whenever required for hydration process, which reduces the usage of traditional curing methods. This mechanism of retaining moisture internal can be achieved by adding certain internal curing agents such as Light Weight Aggregates, Super Absorbent Polymers, Polyethylene Glycol, Wat er Soluble Polymers, Natural or Synthetic Fibers etc. These agents can absorb a lot of water within and enhance the hydration process by releasing water whenever required. They can absorb the moisture either from concrete or from the atmosphere. This method of internal curing is one of the best practices for sustainable concrete which saves a lot of water.\u003c/p\u003e \u003cp\u003eAmong the various approaches for self-curing concrete, usage of Light Weight Aggregates (LWA) and Super Absorbent Polymers (SAP) have gained an attention in the present research due to its effectiveness in improving hydration, reducing shrinkage and enhancing overall performance of concrete. Poly Ethylene Glycol (PEG-400) also played an important role as a self-curing agent in the present research as it is a water-soluble polymer which has an ability to retain moisture.\u003c/p\u003e \u003cp\u003eThe present research aims to investigate the comparative performance of M45 grade self-curing concrete using two internal curing systems: a combination of 50% LWA and 2.5% PEG-400, and 0.2% SAP (hydrogel), each dosed by the weight of cement. The study evaluates key mechanical properties, including workability, compressive strength, and split tensile strength at 7, 14, and 28 days, and compares the results with those of conventionally cured concrete. This research provides insights into the effectiveness of different self-curing agents in enhancing the mechanical performance of high-strength concrete, with implications for sustainable and durable construction practices [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e"},{"header":"Materials \u0026 Methods","content":"\u003cp\u003eOrdinary Portland Cement (OPC 53 grade), natural river sand, crushed coarse aggregates, lightweight aggregates, PEG-400, and hydrogel (SAP) were used. Material properties are summarized in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e. Mix proportions are given in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e, and test methods are listed in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e\n\u003cp\u003eThe materials used in the present investigations are as follows:\u003c/p\u003e\n\u003cp\u003e1. Cement \u0026ndash; OPC 53 grade cement has been used with 3.15 specific gravity. Various physical and chemical tests have been conducted as per Indian Standard codes. The various physical properties have been shown in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e below:\u003c/p\u003e\n\u003cp\u003e2. Aggregates - The fine aggregate used was natural river sand as per IS:383. The specific gravity of sand is found to be 2.626 and fineness modulus obtained is 3.11. The coarse aggregate used in the present research was having 20 mm nominal size. The grain size analysis has been shown in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e \u0026amp; Fig.\u0026nbsp;2 below.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003ePhysical properties of Cement [\u003cspan class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eSr.\u003c/p\u003e\n \u003cp\u003eNo.\u003c/p\u003e\n \u003c/th\u003e\n \u003cth rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eType of Test\u003c/p\u003e\n \u003c/th\u003e\n \u003cth rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eMethod of Test\u003c/p\u003e\n \u003c/th\u003e\n \u003cth rowspan=\"2\" align=\"left\"\u003e\n \u003cp\u003eTest Result\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eLimits as per IS: 269: 2020\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOPC 53 Grade\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eConsistency (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eIS: 4031 Part 4: 1988\u003c/p\u003e\n \u003cp\u003eRA 2019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e28.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSetting Time\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" align=\"left\"\u003e\n \u003cp\u003eIS: 4031 Part 5: 1988 RA 2019\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ea\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eInitial Setting Time, min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eClause 5.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e135\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eShall not be \u0026lt;\u0026thinsp;30 Minutes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eb\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFinal Setting Time, min\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eClause 5.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e255\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eShall not be \u0026gt;\u0026thinsp;600 Minutes\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSoundness, Le\u0026apos;chatelier,\u003c/p\u003e\n \u003cp\u003emm\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eIS: 4031 Part 3: 1988\u003c/p\u003e\n \u003cp\u003eRA 2019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eExpansion Shall be \u0026lt;\u0026thinsp;10mm\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFineness by Blain Air\u003c/p\u003e\n \u003cp\u003ePermeability, M\u003csup\u003e2\u003c/sup\u003e/kg\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eIS: 4031 Part 2: 1988\u003c/p\u003e\n \u003cp\u003eRA 2019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e284.72\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eShall not be less than 225 m\u003csup\u003e2\u003c/sup\u003e/kg\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"4\" align=\"left\"\u003e\n \u003cp\u003eCompressive Strength, N/mm\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ea\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e72\u0026thinsp;\u0026plusmn;\u0026thinsp;1 h, Strength\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" align=\"left\"\u003e\n \u003cp\u003eIS: 4031 Part 6: 1988\u003c/p\u003e\n \u003cp\u003eRA 2019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eShall not be \u0026lt;\u0026thinsp;27 N/mm\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eb\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e168\u0026thinsp;\u0026plusmn;\u0026thinsp;2 h, Strength\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e42.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eShall not be \u0026lt;\u0026thinsp;37 N/mm\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e672\u0026thinsp;\u0026plusmn;\u0026thinsp;4 h, Strength\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e56.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eShall not be \u0026lt;\u0026thinsp;53 N/mm\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3. Water \u0026ndash; Normal tap water has been used for the present research.\u003c/p\u003e\n\u003cp\u003e4. Light Weight Aggregates \u0026ndash; LWA used in this present research has been purchased from Shri Goverdhan Quarry Works, Pavagadh, Vadodara of nominal size 20 mm with proportion of 50% as a replacement of coarse aggregates having specific gravity 2.838. The grain size analysis has been shown in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e below.\u003c/p\u003e\n\u003cp\u003e5. Poly Ethylene Glycol \u0026ndash; In the present research Polyethylene Glycol-400 (PEG-400) with a proportion of 2.5% by the weight of cement has been used which is a water-soluble polymer widely used as an internal curing (self-curing) agent in concrete. Its primary function is to retain moisture within the concrete matrix, ensuring continuous hydration of cement, especially where external curing is challenging or water resources are limited.\u003c/p\u003e\n\u003cp\u003e6. Super Absorbent Polymers \u0026ndash; Hydrogel has been used as SAP\u0026thinsp;\u0026minus;\u0026thinsp;0.2% by the weight of cement. They are synthetic hydrogels used as internal curing agents in concrete to retain moisture, improve hydration, and mitigate shrinkage. Their water-absorbing capacity (up to 500 times their weight) makes them effective for enhancing durability and mechanical performance in low water-to-cement (w/c) ratio concretes.\u003c/p\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\n \u003ch2\u003eMix Proportions\u003c/h2\u003e\n \u003cp\u003eIn this study three mix proportions have been casted which has been shown below:\u0026nbsp;\u003c/p\u003e\n \u003col\u003e\n \u003cli\u003e\n \u003cp\u003e\u003cstrong\u003eControl Mix\u003c/strong\u003e: Conventional concrete with water curing\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003e\u003cstrong\u003eLWA Mix\u003c/strong\u003e: 50% replacement of coarse aggregate with LWA\u003c/p\u003e\n \u003c/li\u003e\n \u003cli\u003e\n \u003cp\u003e\u003cstrong\u003eSAP Mix\u003c/strong\u003e: 0.2% SAP by weight of cement\u003c/p\u003e\n \u003c/li\u003e\n \u003c/ol\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eMix ID\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eS.No.\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMix\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMix ID\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eControl Mix\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eLWA Mix\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM2\u0026ndash;50% LWA\u0026thinsp;+\u0026thinsp;2.5% weight of cement (PEG)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSAP Mix\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM3\u0026ndash;0.2% Hydrogel by weight of cement\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eTests Performed\u003c/h3\u003e\n\u003cdiv class=\"BlockQuote\"\u003e\n \u003cp\u003eVarious tests performed have been performed as per specified IS Code and has been tabulated below in Table \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e:\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab3\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eTests Performed\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSr. No.\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eProperty\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eTests\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eIS Code\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eFresh\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eWorkability\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eIS: 1199\u0026ndash;2018 (2)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"3\" align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"3\" align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eHardened\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCompressive strength test\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eIS: 456\u0026ndash;2000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSplit tensile strength test\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eIS :5816\u0026thinsp;\u0026minus;\u0026thinsp;1959\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eScanning electron microscope\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"Results \u0026 Discussions","content":"\u003cp\u003e\u003cstrong\u003eWorkability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe workability is the fresh concrete property which has been done by using Slump cone test. It has been done for all mix proportions of concrete i.e. conventional concrete, concrete with replacement of aggregates with light weight aggregates and concrete with hydrogel as an addition by the weight of cement. It has been observed that workability decreases for both mixes M2 and M3 as compared to conventional concrete. Workability results obtained using the slump cone test are presented in Table \u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e and illustrated in Fig. \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e. \u0026nbsp;\u003c/p\u003e\n\u003ctable id=\"Tab4\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eWorkability\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eS.No.\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMix\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eWorkability\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e140 mm\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30 mm\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e130 mm\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompressive Strength\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIt is one of the hardened concrete properties to check the strength of concrete for specific grade by using Compression Testing Machine (CTM). Cube specimen of size 150 x 150 x 150 mm has been casted and cured for 7, 14 and 28 days and tested for compressive strength. Three specimens have been casted out of which one has been cured conventionally and other two has been self-curing by using self-curing agents i.e. LWA with PEG-400 and Hydrogel. Results showed that self-cured concrete shows better strength as compared to conventional concrete. It has been observed that after 28 days of self-curing there is approximately 15% increase in compressive strength. Compressive strength results for all mixes are shown in Table \u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e and Fig. \u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u0026nbsp;\u003ctable id=\"Tab5\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eCompressive Strength\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eS.No.\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eMix\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eCompressive Strength, N/mm\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e7 days\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e14 days\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e28 days\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e41.22\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e44.62\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e46.69\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e39.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e44.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e54\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e43.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e53.78\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003ch2\u003e\u003cbr\u003e\u003c/h2\u003e\n\u003ch3\u003e\u003cstrong\u003eSplit Tensile Strength\u003c/strong\u003e\u003c/h3\u003e\n\u003cp\u003eThis test measures the tensile strength of concrete which has the ability to withstand tensile stress of concrete to check the hardened property of concrete. In this test cylindrical specimen of size 150 mm x 300 mm has been used to check the tensile property of self-cured concrete after curing of 7, 14 and 28 days. In the present research, it has been observed that split tensile strength has been decreased for self-cured concrete with LWA\u0026thinsp;+\u0026thinsp;PEG but increases for SAP cured concrete as compared to conventionally cured concrete. Results showed that tensile strength for LWA\u0026thinsp;+\u0026thinsp;PEG self-curing agent has been decreased by 28% approximately, whereas for SAP as self-curing agent tensile strength has been increased by approximately 24%. Split tensile strength results are summarized in Table \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e and Fig. \u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e.\u003c/p\u003e\n\u003ctable id=\"Tab6\" border=\"1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eSplit Tensile Strength\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eS.No.\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eMix\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"3\"\u003e\n \u003cp\u003eSplit Tensile Strength, N/mm\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e7 days\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e14 days\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e28 days\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.95\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.66\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.16\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.31\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5.20\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n\u003ch3\u003eDiscussions\u003c/h3\u003e\n\u003cp\u003eThe reduction in workability observed in self-curing mixes is attributed to water absorption by LWA and SAP. The improved compressive strength is due to continuous internal water supply, enhancing hydration. SAP showed superior tensile performance due to better pore refinement, as supported by SEM observations (Figs. \u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e9\u003c/span\u003e and 10).\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThis research effectively compares the different mechanical properties i.e. workability, compressive strength and split tensile strength of M45 grade for conventional concrete, light weight aggregate concrete with PEG-400 and hydrogel enhanced concrete. Also, comparative analysis of microstructure has been done by using Scanning Electron Microscope test. The results so obtained by conducting different tests have been summarized below:\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003col\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eWorkability for conventional concrete was found to be 140 mm which is approximately 78% higher than the workability obtained for light weight aggregate concrete in which LWA and PEG was used as self-curing agents, whereas for hydrogel enhanced concrete was approximately 7% lower than the workability obtained for conventional concrete.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eCompressive strength test revealed that all the three mixes i.e. M1, M2 \u0026amp; M3 were meeting all the requirements required for compressive strength as for M45 grade concrete compressive strength should be 45 N/mm\u003csup\u003e2\u003c/sup\u003e at 28 days. The results thus obtained shows that there was increase in strength of 3.7%, 20% and 19.5% for M1, M2 \u0026amp; M3 respectively.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eSplit tensile strength results shows that for concrete mix containing hydrogel as self-curing agent has maximum tensile strength but for concrete mix having light weight aggregates with PEG-400 does not meet the requirements of minimum tensile strength which is 29% lower than nominal strength after 28 days of curing.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003cspan\u003e \u003cli\u003e \u003cp\u003eFinally, SEM analysis shows the valuable information in which different microstructural properties of concrete mixes have been identified, which demonstrates how different self-curing agents influences the internal structure of concrete mixes. The SEM photographs show the variation in particles count and arrangement in different samples.\u003c/p\u003e \u003c/li\u003e \u003c/span\u003e \u003c/ol\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe study concludes that self-curing concrete significantly enhances compressive strength and microstructural quality. SAP-based self-curing exhibited balanced performance in both compressive and tensile strength, making it a promising solution for sustainable construction. Overall, it has been concluded that by adding different self-curing agents in different concrete mixes of M45 grade, there was optimal increase in the different mechanical properties of concrete but certain aspects can be found in future for increasing the workability of concrete. Further research can be done for the selection and evaluation of the different curing agents which are necessary to achieve performance enhancement.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eParul Mangal: Conceptualization, methodology, investigation, experimental work, Data curation, Formal analysis, visualization, and Writing \u0026ndash; original draft preparation.Dr. Jayesh Juremalani: Supervision, validation, methodology refinement, resources, review \u0026amp; editing, project administration, and guidance in interpretation of results and manuscript improvement.All authors have read and approved the final manuscript and agree to be accountable for all aspects of the work.\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eI want to express my sincere gratitude to everyone who helped me in conducting this research which involves lightweight aggregates, PEG-400 and hydrogel as self-curing agents. I particularly thank my guide Dr. Jayesh Juremalani under his guidance and expertise research was conducted in proper manner and sequentially. I would also like to appreciate my faculty members and laboratory staff for their help in collecting data and conducting experimental work. I am also grateful for the Micro-Nano R\u0026amp;D Center at Parul University for conducting the Scanning Electron Microscope analysis for the different concrete samples after 28 days of self-curing. Furthermore, I want to express my gratitude for utilizing the resources and facilities provided by the GES Lab, Khodiyar Nagar, Vadodara as they helped a lot in completing the research successfully. Lastly, I am truly thankful to my family and friends for their constant encouragement and understanding during this journey. Their support has been crucial in helping me achieve my goals.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eHamzah N, Saman M, Baghban H, Sam MHM, Faridmehr AR, Muhd Sidek I, Huseien MN, G. F. A review on the use of self-curing agents and its mechanism in high-performance cementitious materials. Buildings. 2022;12(2):152.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNduka DO, Ameh JO, Joshua O, Ojelabi R. Awareness and benefits of self-curing concrete in construction projects: builders and civil engineers\u0026rsquo; perceptions. Buildings. 2018;8(8):109.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSaravanan M, Gopi R, Harihanandh M. (2021). Durability properties of self-compacting self-curing concrete with presaturated light weight aggregates. Materials Today: Proceedings, 45, 7805\u0026ndash;7809.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAl Saffar DM, Saad A, A. J., Tayeh BA. 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J Compos Mater. 2009;43(11):1297\u0026ndash;304.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS. 4031 (2) \u0026ndash; 1999 Determination of Fineness by Blaine Air Permeability Method.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS. 4031 (3) \u0026ndash; 1988 Determination of Soundness of Cement.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS. 4031 (4) \u0026ndash; 1988 Determination of Consistency of Standard Cement Paste.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS. 4031 (5) \u0026ndash; 1988 Determination of Initial and Final Setting Times of Cement.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS. 4031 (6) \u0026ndash; 1988 Determination of Compressive Strength of Cement.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS. 4031 (11) \u0026ndash; 1988 Determination of Density.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS. 2720 (3) \u0026ndash; 1980 Methods of Test for Soils - Determination of Specific Gravity.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS 269. 2015 \u0026ndash; Ordinary Portland Cement \u0026ndash; Specification.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS. 383:1970 \u0026ndash; Specification for Coarse and Fine Aggregates from Natural Sources for Concrete.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS. 2386 (1) \u0026ndash; 1963 Methods of Test for Aggregates for Concrete - Particle Size and Shape.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS. 2386 (3) \u0026ndash; 1963 Methods of Test for Aggregates for Concrete - Specific Gravity, Density, Voids \u0026lsquo;, Absorption and Bulking.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS. 2386 (4) \u0026ndash; 1963 Methods of Test for Aggregates for Concrete - Mechanical Properties.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS 3025. (11) \u0026ndash; 1983 Methods of Sampling and Test (Physical and Chemical) For Water and Waste Water - pH Value.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS 3025. (17) \u0026ndash; 1984 Methods of Sampling and Test (Physical and Chemical) For Water and Waste Water - Non-filterable Residue (Total Suspended Solids).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS 3025. (18) \u0026ndash; 1984 Methods of Sampling and Test (Physical and Chemical) For Water and Wastewater - Volatile and Fixed Residue (Total, Filterable and Non-filterable).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIS 3025. (32) \u0026ndash; 1988 Methods of Sampling and Test (Physical and Chemical) For Water and Wastewater - Chloride.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"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":"discover-materials","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"dime","sideBox":"Learn more about [Discover Materials](https://www.springer.com/journal/43939)","snPcode":"","submissionUrl":"","title":"Discover Materials","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Self-curing, Light weight aggregates, Hydrogel, Cement, SAP, Compressive strength, Workability, Split tensile strength","lastPublishedDoi":"10.21203/rs.3.rs-9186403/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9186403/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eSelf-curing concrete, also known as internal curing concrete, has been developed to overcome the limitations of conventional external curing, particularly in situations involving water scarcity and inadequate curing conditions. In this study, M45 grade concrete incorporating two internal curing systems\u0026mdash;(i) 50% lightweight aggregate (LWA) replacement combined with 2.5% polyethylene glycol (PEG-400), and (ii) 0.2% superabsorbent polymer (SAP) by weight of cement\u0026mdash;was experimentally investigated. The performance of these mixes was evaluated through workability, compressive strength, split tensile strength, and scanning electron microscopy (SEM) tests conducted at curing ages of 7, 14, and 28 days. The results indicated that although both self-curing systems exhibited reduced workability compared to conventional concrete, they achieved a significant improvement in compressive strength of approximately 15\u0026ndash;20% at 28 days. SAP-based concrete showed enhanced split tensile strength, while the LWA\u0026thinsp;+\u0026thinsp;PEG system exhibited a marginal reduction. SEM analysis further confirmed improved hydration and microstructural densification due to the sustained internal moisture supply. Overall, the findings demonstrate that self-curing concrete, particularly when incorporating SAP, offers a viable and effective solution for improving strength and durability in conditions where conventional curing practices are difficult to implement.\u003c/p\u003e","manuscriptTitle":"Comparative Study of Self-Curing Concrete Using Lightweight Aggregates and Hydrogel (SAP) as Internal Curing Agents","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-24 07:44:53","doi":"10.21203/rs.3.rs-9186403/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-28T04:56:38+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-24T12:20:18+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-24T12:19:41+00:00","index":"","fulltext":""},{"type":"submitted","content":"Discover Materials","date":"2026-03-21T14:10:49+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"discover-materials","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"dime","sideBox":"Learn more about [Discover Materials](https://www.springer.com/journal/43939)","snPcode":"","submissionUrl":"","title":"Discover Materials","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"2b3f588d-705b-4f28-b5b5-36e4638493fa","owner":[],"postedDate":"March 24th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-11T08:54:16+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-24 07:44:53","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9186403","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9186403","identity":"rs-9186403","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}