Construction and Building Materials最新文献

{"title":"Performance evaluation of glass powder as a partial precursor in alkali-activated slag (AAS) binder and recycled glass and steel fibers in AAS mortar","authors":"Peifeng Su ,&nbsp;Sunday Eniola ,&nbsp;Jiankai Xie ,&nbsp;Xiang Zhao ,&nbsp;Chigozirim Ugboaja ,&nbsp;Miaomiao Li ,&nbsp;Ruizhe Si ,&nbsp;Qingli Dai ,&nbsp;Yuhuan Fei ,&nbsp;Yun Hang Hu","doi":"10.1016/j.conbuildmat.2025.140757","DOIUrl":"10.1016/j.conbuildmat.2025.140757","url":null,"abstract":"<div><div>To reduce environmental impacts such as landfill waste from glass and tire fibers and to develop sustainable, low-carbon construction materials, this study explores the use of waste glass powder as a precursor in alkali-activated slag (AAS) binders and the recycling of glass particles and tire steel fibers in AAS mortar. The effects of glass powder (GP) as a precursor replacement were compared with those of a control and class F fly ash (FA)-modified AAS binder. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) revealed that GP and FA promote geopolymer formation due to the dissolution of quartz. Nitrogen absorption tests indicated a slight increase in geopolymerization phases with GP replacement, consistent with SEM results and the compressive strength of the AAS binder. In the binder tests, the control AAS binder exhibited the highest compressive strength, while GP-modified samples outperformed FA replacements. GP-modified binders also extended setting times and reduced alkali leaching by over 30 % compared to the control. In mortar systems, replacing natural sand with recycled glass sand (GS) increased 28-day compressive strength by approximately 5.1 %, while adding recycled tire steel fiber (RTSF) improved compressive strength by up to 9.1 %, splitting tensile strength by 30 %, and flexural strength by 2.5 % compared to non-reinforced mixes. Sustainability analysis indicated that using GP as a partial precursor in AAS binders can reduce CO₂ emissions by nearly 5 % compared to normal AAS samples. This study uniquely compares GP and FA as partial precursors and introduces an integrated approach by simultaneously incorporating recycled glass sand and RTSF in mortars, thereby enhancing the mechanical properties, durability, and sustainability of AAS materials.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"473 ","pages":"Article 140757"},"PeriodicalIF":7.4,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functionalizing lignin with introducing benzene rings and adjusting intramolecular polarity for improving bituminous photooxidative aging resistance","authors":"Bianyang He ,&nbsp;Shiheng Wan ,&nbsp;Xuemei Li ,&nbsp;Chuyue Xu ,&nbsp;Yixin Li ,&nbsp;Jianying Yu ,&nbsp;Bo Xiong ,&nbsp;Yafang Tang ,&nbsp;Lei Zhu","doi":"10.1016/j.conbuildmat.2025.141024","DOIUrl":"10.1016/j.conbuildmat.2025.141024","url":null,"abstract":"<div><div>Lignin (LG) is utilized to strengthen the photooxidative aging resistance of bitumen due to its ability to absorb ultraviolet (UV) radiation and scavenge free radicals. However, the anti-aging performance of LG is constrained by a dilemma: at low dosages, the functional structures are insufficient; while at high dosages, uneven dispersion occurs within the bituminous matrix. Herein, we demonstrate a strategy to functionalize LG for improving bituminous photooxidative aging resistance through synergistically introducing benzene rings and adjusting intramolecular polarity. Specifically, 4,4′-diphenylmethane diisocyanate (MDI) functionalized LG (MFLG) was synthesized via covalent bonding between hydroxyl and isocyanate groups, and its structural properties were analyzed using multiple characterization techniques. The results revealed that the introduction of benzene rings enhanced the particle size, hydrophobic, thermal stability, and UV absorption capacity of LG. Meanwhile, bitumen modified with MFLG (MFLG-MB) demonstrated superior resistance to photooxidative aging compared to LG modified bitumen (LG-MB) and pristine bitumen (PB). Furthermore, molecular simulations (MS) elucidated the anti-aging mechanism. The incorporation of MDI improved the dispersion of LG within the bituminous matrix, as evidenced by binding energy calculations, which was beneficial for anti-aging protection of bitumen. Snapshots, electrostatic potential, and dipole moment values further demonstrated that MFLG exhibited stronger intramolecular polarity and higher affinity for asphaltenes compared to LG. These properties underscored MFLG's critical role in inhibiting asphaltene gelation for enhancing the photooxidative aging resistance significantly. This finding highlights a novel strategy to improve the anti-aging effectiveness of LG in bitumen by increasing aromatic groups and optimizing intramolecular polarity.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"473 ","pages":"Article 141024"},"PeriodicalIF":7.4,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recycling waste polyethylene foam into fired clay bricks: A sustainable solution for lightweight and thermally efficient building materials","authors":"Ahmet Yavaş ,&nbsp;Şevket Onur Kalkan ,&nbsp;Mücahit Sütçü ,&nbsp;Lütfullah Gündüz","doi":"10.1016/j.conbuildmat.2025.140967","DOIUrl":"10.1016/j.conbuildmat.2025.140967","url":null,"abstract":"<div><div>Recycling polymer waste by incorporating it into building materials offers a sustainable solution to pollution and environmental challenges. This pioneering study explores the use of waste polyethylene foam (WPEF) as an additive in fired clay bricks, examining its impact on physical, thermal, mechanical, and durability properties. Bricks with 0 %–10 % WPEF content were fired at 900°C and 1000°C to assess their performance. Results show that increasing WPEF reduces bulk density significantly—up to 23.3 % at 900°C and 27.5 % at 1000°C. At 10 % WPEF, the density difference between the two temperatures narrows to 2 %, indicating 900°C as a more energy-efficient option. Thermal conductivity improves by up to 69.63 % at 900°C and 75.84 % at 1000°C, achieving a minimum value of 0.190 W/mK. While water absorption stays within limits at WPEF levels up to 7.5 %, it slightly exceeds thresholds at 10 %. Compressive strength decreases with higher WPEF content due to increased porosity, with bricks containing up to 7.5 % WPEF classified as first-class. Higher WPEF levels also reduce freeze-thaw resistance, particularly at 1000°C, due to crack formation. This study highlights WPEF's potential to produce lightweight, thermally efficient, and eco-friendly bricks with optimized WPEF content and firing conditions.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"473 ","pages":"Article 140967"},"PeriodicalIF":7.4,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143715718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of talc on the microstructure and properties of zirconium-free microcrystalline opaque raw glazes for slabs","authors":"Jianfeng Wu,&nbsp;Jiajun Yuan,&nbsp;Xiaohong Xu,&nbsp;Deng Zhang,&nbsp;Yunliang Zhang,&nbsp;Xuyang Ding,&nbsp;Chenlong Yang","doi":"10.1016/j.conbuildmat.2025.141017","DOIUrl":"10.1016/j.conbuildmat.2025.141017","url":null,"abstract":"<div><div>Zirconium opaque glazes are the most widely used opacifier due to their stability and adaptability to sintering temperatures, and are highly used in building materials to meet both decorative and functional needs. The high cost of zirconium materials and the high-temperature melting required for frit glazes result in increased energy usage and production costs. There is an urgent need for a more affordable and efficient alternative in raw glazes. Zirconium-free microcrystalline opaque raw glazes, formulated from natural minerals, eliminate zirconium sand, reducing production costs by 15–20 % per tonne while lowering energy consumption and carbon emissions. And talc as raw materials, and investigated the influence of talc additions on both the microstructure and properties. The appropriate incorporation of talc can significantly lower the melting temperature, enhance the hardness and toughness, and promote a uniform distribution of small closed pores. The glaze yields magnesium-aluminum spinel and cordierite microcrystals, as well as a uniform distribution of small closed pores, which collectively contribute to improved opacity. The A3 sample, with a talc addition of 19.76 wt%, fired at 1240 ℃, had the best performance, exhibiting a high hardness of 7.35 GPa, a fracture toughness of 2.25 MPa·m^1/2, a roughness (Sa) of 0.3356 μm, a gloss of 67.67 GU, and chromaticity parameters of L* 87.38, a* −1.90, and b* 7.41. The Vickers microhardness of the glazes in this study was higher than that of commercial zirconium-based ceramic glazes, indicating that this type of raw glaze can replace the widely used zirconium-containing ceramic opaque glazes.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"473 ","pages":"Article 141017"},"PeriodicalIF":7.4,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pull-out behavior of inorganic-bonded bamboo composite connections with glued-in rod","authors":"Ernian Zhao ,&nbsp;Shaohua Yu ,&nbsp;Fei Wang ,&nbsp;Xin Zhang ,&nbsp;Chao Yang","doi":"10.1016/j.conbuildmat.2025.140998","DOIUrl":"10.1016/j.conbuildmat.2025.140998","url":null,"abstract":"<div><div>Inorganic-bonded bamboo composite (<em>InorgBam</em>) is a new engineered bamboo composite material made of bamboo fiber strips and magnesium oxysulfide (MOS) inorganic adhesive. With advantages of high strength, high stiffness, and excellent fire resistance, glued-in rod (GiR) connections serve as the primary connection form in modern engineered bamboo and wood structures. To study pull-out behavior of GiR in <em>InorgBam</em>, pull-out tests were conducted in two grain orientations: parallel- and perpendicular-to-grain. Effects of threaded rod grade, anchorage length, and edge distance on failure mode, pull-out load-carrying capacity, and ductility of GiR connections were analyzed. Results revealed that specimens exhibited four failure modes: shear failure of <em>InorgBam</em> around adhesive, bonding failure at <em>InorgBam</em>-adhesive interface, splitting failure and threaded rod yield. GiR specimens with insufficient edge distance exhibited characteristics of splitting failure parallel-to-grain. Therefore, it is recommended that the edge distance of the GiR connections in <em>InorgBam</em> be no less than six times the rod diameter (6<em>d</em>). GiR specimens perpendicular-to-grain demonstrated higher load-carrying capacity than those parallel-to-grain. For specimens without rod yield failure, load-carrying capacity increases linearly with increasing slenderness ratio of rod. The average bond strength of GiR specimens parallel- and perpendicular-to-grain is 6.55 MPa and 8.63 MPa, respectively. Finally, the bond stress-slip relationships of GiR connections in <em>InorgBam</em> were derived from test results according to existing bond stress-slip models, and a calculation formula for pull-out load-carrying capacity was then proposed for GiR connections in <em>InorgBam</em>.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"473 ","pages":"Article 140998"},"PeriodicalIF":7.4,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143715719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A universal formula for calculating the penetration depth in concrete structures at projectile velocity below 1000 m/s","authors":"Chenglong Huang ,&nbsp;Zhenqing Wang ,&nbsp;Yeqing Chen ,&nbsp;Shutao Li ,&nbsp;Mengnan Dai ,&nbsp;Shouji Zhao ,&nbsp;Xihan Shao ,&nbsp;Lumeng Li ,&nbsp;Tianchun Ai","doi":"10.1016/j.conbuildmat.2025.141042","DOIUrl":"10.1016/j.conbuildmat.2025.141042","url":null,"abstract":"<div><div>In recent years, with the increasing use of reinforcement and widespread use of ultra-high performance concrete (UHPC) materials in concrete structures, it is difficult to accurately calculate the penetration depth of these concrete structures by existing formulas. To develop a universal formula applicable to all types of concrete structures, this paper investigates and evaluates existing formulas for calculating the penetration depth of concrete structures. Based on these formulas, we derive a new expression considering the volume reinforcement ratio and a preliminary form of the universal formula. Two penetration tests were conducted on a normal concrete structure and an UHPC structure, followed by the establishment and validation of two numerical models based on the test results. According to regression analysis and linear interpolation methods, we determine the reinforcement ratio impact factor (<em>α</em>) in the new expression, yielding the final form of the universal formula. Finally, validation with 26 sets of test data and comparison with existing formulas demonstrate that the proposed formula in this paper offers higher calculation accuracy and better universality. The calculation formula presented in this paper is applicable not only to normal concrete structures but also to UHPC structures. This formula holds significant reference value for the protective design of concrete structures, providing a basis for evaluating the anti-penetration performance of concrete structures.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"473 ","pages":"Article 141042"},"PeriodicalIF":7.4,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Swelling behavior and microscopic characteristics of a hydrophilic seal in composite geomembrane cutoff walls exposed to various metal-rich solutions","authors":"Min Wang ,&nbsp;Wei-Yi Xia ,&nbsp;Xian-Lei Fu ,&nbsp;Ji-Ying Fan ,&nbsp;Zi-Han Lu ,&nbsp;Yan-Jun Du","doi":"10.1016/j.conbuildmat.2025.140972","DOIUrl":"10.1016/j.conbuildmat.2025.140972","url":null,"abstract":"<div><div>This study aimed to investigate swelling behavior, organic composition elution, and microscopic characteristics of a hydrophilic seal exposed to various metal-rich solutions. Results indicated swelling ratios of hydrophilic seal in the monovalent cation (sodium) solutions increased over time until reaching equilibrium; whereas it initially peaked, then gradually decreased and finally stabilized in the multivalent cation solutions. The cation valence was identified as the most significant factor influencing the swelling ratio of weight at equilibrium (<em>S</em>_we), as compared to the other influencing factors (e.g., cation and anion concentrations). The <em>S</em>_we in the 100 mM sodium salt solutions ranged from 328 % to 428 %, which was approximately 10–40 times higher than that in the 100 mM multivalent cation solutions (11–38 %)<em>.</em> Based on the microscopic test results, the interaction mechanisms between the seal and metals were interpreted as follows: (1) cations in the testing liquids migrated into the hydrophobic matrix, which in turn reduced osmotic pressure and swelling ability of the seal; and (2) multivalent cations in the testing liquids exchanged with ionized sodium released from the sodium polyacrylate hydrogels, which resulted in chain aggregation or collapse. Therefore, the hydrophilic seal exhibited different swelling behavior in the multivalent cation solution from that in the monovalent cation solution.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"473 ","pages":"Article 140972"},"PeriodicalIF":7.4,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synergistic effects of carbonated magnesium slag and calcined coal gangue on composite cement properties","authors":"Ziqi Tang ,&nbsp;Genshen Li ,&nbsp;Songhui Liu ,&nbsp;Haibo Zhang ,&nbsp;Shuqiong Luo ,&nbsp;Hao Xiang ,&nbsp;Shuai Zhao ,&nbsp;Xuemao Guan","doi":"10.1016/j.conbuildmat.2025.140794","DOIUrl":"10.1016/j.conbuildmat.2025.140794","url":null,"abstract":"<div><div>This study investigates the synergistic effects of carbonated magnesium slag (C-MS) and calcined coal gangue (T-CG) on the properties of composite cement. Various blends of C-MS and T-CG were used to substitute 50 % of ordinary Portland cement, with ratios ranging from 0:100–100:0. A combination of multiple techniques, namely compressive strength testing, isothermal calorimetry, X-ray diffraction (XRD), thermogravimetric analysis-derivative thermogravimetric analysis (TG-DTG), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), and low-field nuclear magnetic resonance (NMR), was systematically employed to examine the mechanical properties, hydration kinetics, microstructure, and phase composition of the composite cements. Results demonstrated that the optimal C-MS: T-CG ratio for mechanical performance is approximately 4:1. While early-age strength was initially lower than the control group, most composite blends achieved comparable or superior strength by 60 d. Hydration kinetics revealed a synergistic effect between C-MS and T-CG, with C50 + TCG50 exhibiting the highest cumulative heat release. Microstructural analysis showed enhanced formation of needle-like AFt and C-S-H gel in the composite cements. XRD and TG-DTG analyses further confirmed the formation of carboaluminate phases (including Hc, Mc) and a lower of content Ca(OH)₂ in composite cements, especially those with a relatively higher content of T-CG. FTIR indicated the formation of more Si-rich C-S-H gel in the blended systems. This research provides valuable insights into the complex interactions between C-MS and T-CG in composite cements, which could potentially contribute to the further development and optimization of such composite cements in the field of civil engineering.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"473 ","pages":"Article 140794"},"PeriodicalIF":7.4,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical behavior of ultra-high toughness engineered cementitious composite using seawater coral sand exposed to elevated temperature","authors":"Peng Yu,&nbsp;Cun Yu,&nbsp;Zheng Chen,&nbsp;Zhaoyong Ren","doi":"10.1016/j.conbuildmat.2025.141016","DOIUrl":"10.1016/j.conbuildmat.2025.141016","url":null,"abstract":"<div><div>Island construction poses new challenges to material development. High-performance Seawater Coral Sand Engineered Cementitious Composite (SC-ECC) with high toughness can achieve by using polyethylene (PE) fibers. However, when suffering from high temperature, PE fibers tend to melt and plug the pores, blocking vapors from escaping the matrix and causing it to crack. To address this problem, in this paper, polyoxymethylene (POM) fibers with good thermo-mechanical property are explored to replace the PE fibers in the SC-ECC to remain a good mechanical feature exposed to elevated temperature. The high-temperature tests were conducted to obtain the cracking temperature variations of SC-ECC with different fiber content. The bursting resistance mechanism of POM fiber was revealed by means of thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and mercury intrusion porosity (MIP) microstructural analyses, and the bursting probability was discussed from the perspective of pore structure. The mechanical performance tests of SC-ECC with various fiber replacement rates at different temperatures were carried out, and a tensile constitutive model was proposed. The results indicated that the specimens with POM fibers did not experience spalling or fracture within the temperature range of 20–700°C, while those with only PE fibers exhibited fracture at 300℃. After melting, POM fibers easily volatilize without agglomeration and blockage of pores, leaving behind larger diameter voids. This facilitates the alleviation of high vapor pressure generated from water loss between 200 and 300℃. The tensile properties of POM-incorporated specimens slightly decrease with increasing POM content, while the compressive strength gradually increases. Regardless of the fiber type, strain hardening behavior of SC-ECC was lost at 200℃. Beyond 300℃, ECC with pure PE completely lost its mechanical performance due to bursting, while that with POM fibers consistently maintained good compressive and tensile strength up to 400°C. The addition of POM significantly enhances the compressive strength of SC-ECC at any temperature (20–400℃). A comprehensive evaluation demonstrated an excellent mechanical performance and high temperature spalling resistance of SC-ECC with 1.5 vol% PE and 0.5 vol% POM.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"473 ","pages":"Article 141016"},"PeriodicalIF":7.4,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143715717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical properties of metakaolin and granulated blast-furnace slag-based roller-compacted geopolymer concrete containing 100 % reclaimed asphalt pavement: Optimization and prediction via response surface methodology","authors":"Ali Bashash ,&nbsp;Reza Saleh Ahari ,&nbsp;Gholam Hossein Shahverdizadeh","doi":"10.1016/j.conbuildmat.2025.140956","DOIUrl":"10.1016/j.conbuildmat.2025.140956","url":null,"abstract":"<div><div>The growing volume of Reclaimed Asphalt Pavement (RAP) waste, combined with the environmental impact of high cement production, highlights the urgent need for sustainable solutions. Alternative binders and efficient waste utilization offer promising ways to address these challenges. Unlike traditional concrete, which relies on supplementary cementing materials (SCM) to enhance strength, geopolymer concrete uses aluminosilicate sources (AS) to drive the geopolymerization process. This study explores the mechanical properties of roller-compacted geopolymer concrete (RCGC), focusing on the role of metakaolin (MK), both with and without granulated blast furnace slag (GBFS) as an additive AS. Hydrated lime (HL) was chosen as an alkali activator due to its affordability, availability, and its known effect on accelerating the setting process in geopolymer mixtures. The research examines how variations in sodium hydroxide molarity, HL content, and GBFS ratio influence the strength of RCGC. The results showed that increasing HL content had a negative impact on the mechanical properties, while higher concentrations of GBFS and sodium hydroxide (SH) significantly improved compressive, tensile, and flexural strengths. The optimal mix design, identified using response surface methodology (RSM) with a score of 0.96, consisted of 10 M SH, no HL, and 40 % GBFS, achieving a maximum 28-day compressive strength of 15.9 MPa. Distinct failure modes were observed: MK-based RCGC exhibited mortar failure, while mixes containing 100 % GBFS showed aggregate failure, indicating better structural integrity. These findings suggest that RCGC can serve as a sustainable and practical solution for low-volume road applications, offering both enhanced performance and environmental benefits.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"473 ","pages":"Article 140956"},"PeriodicalIF":7.4,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143715722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}