Construction and Building Materials最新文献_第10页

Synthesis and evaluation of ethyl α-cyanoacrylate-based composites with alkaline solid waste additives as initiators for structural repair 以碱性固体废物添加剂为引发剂的乙基α-氰基丙烯酸酯基复合材料的合成与评价

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-03 DOI: 10.1016/j.conbuildmat.2025.145092

Haoyu Wang , Han Gao , Hongqi Yang , Huangqi Zhang , Xianhui Zhao

Concrete structural repair demands materials capable of rapid setting and high early strength, especially under emergency or low-temperature conditions. This study explores the novel use of industrial alkaline solid wastes—soda residue powder (SRP) and combusted ash powder (CAP)—as dual-functional initiators and fillers to accelerate the polymerization of ethyl α-cyanoacrylate (ECA) for rapid-hardening repair composites. The reaction kinetics, exothermic behavior, and hardening characteristics of ECA with SRP and/or CAP were systematically investigated under sub-zero (–5 °C to 0 °C) and ambient temperatures. Microstructural and compositional changes were analyzed using SEM-EDS, XRD, FTIR, and TG-DSC. The compressive strength and interfacial bonding performance of the composites within cement matrices were also evaluated. Results indicated that both SRP and CAP significantly accelerated ECA curing, reducing the hardening time to within 20 s even at sub-zero temperatures. The reaction was highly exothermic and involved acid-base neutralization, leading to reduced pH and electrical conductivity in the composites. ECA composites with SRP exhibited higher density, superior compressive strength, and improved adhesion to cement compared to those with CAP. This work provides a sustainable strategy for repurposing solid wastes into high-performance, rapid-curing repair materials, contributing to both waste valorization and the development of advanced construction composites.

混凝土结构修复要求材料能够快速凝结，早期强度高，特别是在紧急或低温条件下。本研究探索了利用工业碱性固体废弃物——碱渣粉（SRP）和燃烧灰粉（CAP）作为双功能引发剂和填料，加速α-氰基丙烯酸酯乙酯（ECA）在快速硬化修复复合材料中的聚合。在零下（-5°C至0°C）和环境温度下，系统研究了SRP和/或CAP对ECA的反应动力学、放热行为和硬化特性。采用SEM-EDS、XRD、FTIR和TG-DSC分析了样品的微观结构和成分变化。并对复合材料在水泥基体中的抗压强度和界面粘结性能进行了评价。结果表明，SRP和CAP均能显著加速ECA固化，即使在零下温度下也能将硬化时间缩短至20 s以内。该反应是高度放热的，涉及酸碱中和，导致复合材料的pH和电导率降低。与CAP相比，含有SRP的ECA复合材料具有更高的密度、优异的抗压强度和更好的水泥粘附性。这项工作为将固体废物重新利用为高性能、快速固化的修复材料提供了一种可持续的策略，有助于废物增值和先进建筑复合材料的发展。

{"title":"Synthesis and evaluation of ethyl α-cyanoacrylate-based composites with alkaline solid waste additives as initiators for structural repair","authors":"Haoyu Wang , Han Gao , Hongqi Yang , Huangqi Zhang , Xianhui Zhao","doi":"10.1016/j.conbuildmat.2025.145092","DOIUrl":"10.1016/j.conbuildmat.2025.145092","url":null,"abstract":"<div><div>Concrete structural repair demands materials capable of rapid setting and high early strength, especially under emergency or low-temperature conditions. This study explores the novel use of industrial alkaline solid wastes—soda residue powder (SRP) and combusted ash powder (CAP)—as dual-functional initiators and fillers to accelerate the polymerization of ethyl α-cyanoacrylate (ECA) for rapid-hardening repair composites. The reaction kinetics, exothermic behavior, and hardening characteristics of ECA with SRP and/or CAP were systematically investigated under sub-zero (–5 °C to 0 °C) and ambient temperatures. Microstructural and compositional changes were analyzed using SEM-EDS, XRD, FTIR, and TG-DSC. The compressive strength and interfacial bonding performance of the composites within cement matrices were also evaluated. Results indicated that both SRP and CAP significantly accelerated ECA curing, reducing the hardening time to within 20 s even at sub-zero temperatures. The reaction was highly exothermic and involved acid-base neutralization, leading to reduced pH and electrical conductivity in the composites. ECA composites with SRP exhibited higher density, superior compressive strength, and improved adhesion to cement compared to those with CAP. This work provides a sustainable strategy for repurposing solid wastes into high-performance, rapid-curing repair materials, contributing to both waste valorization and the development of advanced construction composites.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"507 ","pages":"Article 145092"},"PeriodicalIF":8.0,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145883269","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}

引用次数: 0

Degradation mechanism and life prediction of Q355NH weathering steel under corrosion-fatigue alternation 腐蚀-疲劳交替作用下Q355NH耐候钢的降解机理及寿命预测

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-03 DOI: 10.1016/j.conbuildmat.2025.144726

Qi Guo, Jingwei Lu, Ying Xing, Wenyu Zhang, Hongxiang Wang, Yi Peng

The application of uncoated weathering steel in bridges has increased due to its superior corrosion resistance. During service, these structures are commonly subjected to the combined effects of corrosion and fatigue. However, current experimental studies fail to accurately represent the actual performance degradation of weathering steel under coupled corrosion-fatigue conditions. To address this, this study proposes an accelerated corrosion-fatigue alternating test protocol and conducts a 135-day coupling test on Q355NH weathering steel and Q355 steel. The results show that under corrosion-fatigue coupling, the mass loss rate (η) increases linearly, rather than following a power-law growth pattern, with η under coupling being significantly higher. Macro- and micro-observations revealed periodic cracking and healing of the rust layer. X-ray diffraction (XRD) analysis clarified the evolution of the rust layer composition, and 3D morphological scanning established a power-law relationship between pit size and corrosion periods. Failure mechanisms under corrosion-fatigue coupling were also investigated. Two-stage linear S-N data were derived, with slopes of −5.00 and −0.91, respectively. In the second stage, the corrosion effect becomes more pronounced, resulting in a steeper slope, making conventional S-N data inadequate. Finally, life prediction was performed by integrating local strain-strain method (LSSM), continuous damage mechanics method (CDMM), and an iterative numerical pit evolution model. It was found that LSSM fails to capture life degradation in the second stage, while CDMM provides a reliable life prediction with an error margin within 50 %.

无涂层耐候钢由于其优异的耐腐蚀性，在桥梁中的应用越来越多。在使用过程中，这些结构通常受到腐蚀和疲劳的综合影响。然而，目前的实验研究并不能准确反映耐候钢在腐蚀-疲劳耦合条件下的实际性能退化情况。为了解决这一问题，本研究提出了一种加速腐蚀-疲劳交替试验方案，并对Q355NH耐候钢和Q355钢进行了135天的耦合试验。结果表明：在腐蚀-疲劳耦合作用下，试样的质量损失率（η）呈线性增长，而不是幂律增长，其中η显著增大；宏观和微观观察显示锈层有周期性的开裂和愈合。x射线衍射（XRD）分析明确了锈层成分的演变，三维形态扫描建立了坑尺寸与腐蚀周期之间的幂律关系。研究了腐蚀-疲劳耦合作用下的失效机理。得到两阶段线性S-N数据，斜率分别为- 5.00和- 0.91。在第二阶段，腐蚀效应变得更加明显，导致坡度更陡，使得常规的S-N数据不充分。最后，结合局部应变-应变法（LSSM）、连续损伤力学方法（CDMM）和迭代数值坑演化模型进行寿命预测。发现LSSM无法捕捉第二阶段的寿命退化，而CDMM提供了可靠的寿命预测，误差范围在50% %以内。

{"title":"Degradation mechanism and life prediction of Q355NH weathering steel under corrosion-fatigue alternation","authors":"Qi Guo, Jingwei Lu, Ying Xing, Wenyu Zhang, Hongxiang Wang, Yi Peng","doi":"10.1016/j.conbuildmat.2025.144726","DOIUrl":"10.1016/j.conbuildmat.2025.144726","url":null,"abstract":"<div><div>The application of uncoated weathering steel in bridges has increased due to its superior corrosion resistance. During service, these structures are commonly subjected to the combined effects of corrosion and fatigue. However, current experimental studies fail to accurately represent the actual performance degradation of weathering steel under coupled corrosion-fatigue conditions. To address this, this study proposes an accelerated corrosion-fatigue alternating test protocol and conducts a 135-day coupling test on Q355NH weathering steel and Q355 steel. The results show that under corrosion-fatigue coupling, the mass loss rate (<em>η</em>) increases linearly, rather than following a power-law growth pattern, with <em>η</em> under coupling being significantly higher. Macro- and micro-observations revealed periodic cracking and healing of the rust layer. X-ray diffraction (XRD) analysis clarified the evolution of the rust layer composition, and 3D morphological scanning established a power-law relationship between pit size and corrosion periods. Failure mechanisms under corrosion-fatigue coupling were also investigated. Two-stage linear S-N data were derived, with slopes of −5.00 and −0.91, respectively. In the second stage, the corrosion effect becomes more pronounced, resulting in a steeper slope, making conventional S-N data inadequate. Finally, life prediction was performed by integrating local strain-strain method (LSSM), continuous damage mechanics method (CDMM), and an iterative numerical pit evolution model. It was found that LSSM fails to capture life degradation in the second stage, while CDMM provides a reliable life prediction with an error margin within 50 %.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"507 ","pages":"Article 144726"},"PeriodicalIF":8.0,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145883212","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}

引用次数: 0

Cracking resistance and fatigue behavior of cold-mixed semi-flexible pavements incorporating emulsified asphalt and cementitious materials 含乳化沥青和胶凝材料的冷拌半柔性路面的抗裂性和疲劳性能

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-03 DOI: 10.1016/j.conbuildmat.2025.144897

Xiaoyu Liu , Xianhua Wang , Kuanghuai Wu , Fengming Ren , Yunpeng Yue , Chen Li , Xu Cai , Shengyu Wang

Semi-flexible pavement (SFP) is a composite of asphalt mixture and cementitious grout, offering high strength and rutting resistance. However, traditional grouted semi-flexible pavement (G-SFP) requires a complex process, involving the formation of a large-void asphalt mixture matrix followed by the infusion of a cementitious grout. To address this, this paper proposes a cold-mixed semi-flexible pavement (C-SFP) prepared by sequentially mixing emulsified asphalt, a non-stick wheel additive, and cementitious materials. This direct mixing approach increases pavement compactness, reduces internal voids, and significantly improves construction efficiency compared to conventional methods. Six mixtures with different emulsified asphalt and cementitious materials dosages were prepared to examine the cracking resistance of C-SFP. Fatigue and cracking resistance of C-SFP were assessed using dynamic modulus, four-point bending, and semicircular bending (SCB) tests, with G-SFP serving as a reference, respectively. Results indicated that the dynamic modulus rose with frequency but declined with temperature, reflecting the characteristic viscoelasticity of SFP mixtures. C-SFPs exhibit higher modulus and lower phase angles than G-SFPs, indicating stronger interfacial bonding and better load transfer, with the 30 % mortar content achieving the optimal balance between stiffness and flexibility. C-SFP with 30 % grout content and 4.5 % effect asphalt content demonstrated the best fatigue performance, reflecting an optimal trade-off between stiffness and flexibility, while SCB results indicate that increasing cementitious materials content to 40 % can improve both strength and ductility. Overall, these findings present a new and effective approach for designing and constructing semi-flexible pavements with enhanced mechanical integrity and construction efficiency.

半柔性路面（SFP）是一种由沥青混合料和胶凝浆料组成的复合材料，具有高强度和抗车辙性。然而，传统的注浆半柔性路面（G-SFP）需要一个复杂的过程，包括形成大空隙沥青混合料基质，然后注入胶凝浆液。为了解决这个问题，本文提出了一种冷拌半柔性路面（C-SFP），该路面由乳化沥青、不粘车轮添加剂和胶凝材料依次混合而成。与传统方法相比，这种直接混合方法增加了路面密实度，减少了内部空隙，显著提高了施工效率。制备了6种不同乳化沥青和胶凝材料掺量的混合料，考察了C-SFP的抗裂性能。以G-SFP为参照，分别采用动模量、四点弯曲和半圆弯曲（SCB）试验对C-SFP的疲劳和抗裂性进行了评估。结果表明，动模量随频率升高而升高，但随温度升高而降低，反映了SFP混合料的粘弹性特性。与G-SFPs相比，C-SFPs具有更高的模量和更低的相位角，表明界面结合更强，载荷传递更好，30% %砂浆含量达到了刚度和柔韧性的最佳平衡。C-SFP砂浆掺量为30% %和4.5 %的效果沥青掺量表现出最佳的疲劳性能，反映了刚度和柔韧性之间的最佳权衡，而SCB结果表明，将胶凝材料掺量增加到40% %可以同时提高强度和延性。总的来说，这些研究结果为设计和施工提高机械完整性和施工效率的半柔性路面提供了一种新的有效方法。

{"title":"Cracking resistance and fatigue behavior of cold-mixed semi-flexible pavements incorporating emulsified asphalt and cementitious materials","authors":"Xiaoyu Liu , Xianhua Wang , Kuanghuai Wu , Fengming Ren , Yunpeng Yue , Chen Li , Xu Cai , Shengyu Wang","doi":"10.1016/j.conbuildmat.2025.144897","DOIUrl":"10.1016/j.conbuildmat.2025.144897","url":null,"abstract":"<div><div>Semi-flexible pavement (SFP) is a composite of asphalt mixture and cementitious grout, offering high strength and rutting resistance. However, traditional grouted semi-flexible pavement (G-SFP) requires a complex process, involving the formation of a large-void asphalt mixture matrix followed by the infusion of a cementitious grout. To address this, this paper proposes a cold-mixed semi-flexible pavement (C-SFP) prepared by sequentially mixing emulsified asphalt, a non-stick wheel additive, and cementitious materials. This direct mixing approach increases pavement compactness, reduces internal voids, and significantly improves construction efficiency compared to conventional methods. Six mixtures with different emulsified asphalt and cementitious materials dosages were prepared to examine the cracking resistance of C-SFP. Fatigue and cracking resistance of C-SFP were assessed using dynamic modulus, four-point bending, and semicircular bending (SCB) tests, with G-SFP serving as a reference, respectively. Results indicated that the dynamic modulus rose with frequency but declined with temperature, reflecting the characteristic viscoelasticity of SFP mixtures. C-SFPs exhibit higher modulus and lower phase angles than G-SFPs, indicating stronger interfacial bonding and better load transfer, with the 30 % mortar content achieving the optimal balance between stiffness and flexibility. C-SFP with 30 % grout content and 4.5 % effect asphalt content demonstrated the best fatigue performance, reflecting an optimal trade-off between stiffness and flexibility, while SCB results indicate that increasing cementitious materials content to 40 % can improve both strength and ductility. Overall, these findings present a new and effective approach for designing and constructing semi-flexible pavements with enhanced mechanical integrity and construction efficiency.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"507 ","pages":"Article 144897"},"PeriodicalIF":8.0,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145883177","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}

引用次数: 0

Low-carbon fire-resistant masonry mortar incorporating decoration waste recycled aggregates for sustainable building envelopes 低碳耐火砌体砂浆结合装饰废料再生骨料可持续建筑围护结构

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-03 DOI: 10.1016/j.conbuildmat.2025.145065

Pinghua Zhu , Tianqi Tao , Hongyun Chen , Chunhong Chen , Feifei Jiang , Hui Liu , Xiancui Yan , Lei Yang

The construction industry is one of the largest energy consumers and a significant source of carbon emissions. Energy-efficient building envelopes are essential, but conventional insulation materials like expanded polystyrene (EPS) pose serious fire risks and emit CO₂ when burned. This study addresses fire safety and carbon reduction by using decoration waste as recycled aggregates (DWRA) and incorporating silica aerogel to formulate a low-carbon, aerogel-enhanced masonry mortar, and, to the best of our knowledge, provides the first systematic evaluation of DWRA–aerogel fire-resistant masonry mortar. Mixtures with 0–30 % aerogel were subjected to fire-simulation experiments at 200 °C, 400 °C, 600 °C, and 800 °C, followed by testing at ambient temperature. The incorporation of aerogel improved thermal insulation, reducing thermal conductivity from 0.64 W/(m·K) to 0.39 W/(m·K). At 800 °C, the 30 % aerogel mix retained about 40 % of compressive strength (compared with 35 % for the control), reduced mass loss by up to 11.1 %, and exhibited suppressed cracking, indicating improved thermal stability. A cradle-to-gate economic and environmental assessment shows that the material cost of DWAMM increases from 70 to 671 USD/m³ but remains below that of commercial aerogel mortar (≈795.3 USD/m³), while its CO₂ emissions of 734.6–811.3 kg CO₂/m³ are 8.8–17.5 % lower than those of commercial aerogel insulating mortar (890 kg CO₂-eq/m³). Comprehensive characterization, including mass loss, thermal conductivity (GB/T 10294–2008), compressive strength (JGJ/T 70–2009), flexural strength (GB/T 17671–2021), ultrasonic pulse velocity (ASTM C597–16), and scanning electron microscopy, confirms that the 20–30 % aerogel mixes achieve a favorable balance among fire resistance, thermal insulation, economic performance, and embodied-carbon reduction, supporting the development of low-carbon fire-resistant building envelopes.

建筑行业是最大的能源消费者之一，也是碳排放的重要来源。节能建筑围护结构是必不可少的，但像发泡聚苯乙烯（EPS）这样的传统保温材料存在严重的火灾风险，燃烧时会排放二氧化碳。本研究通过将装饰垃圾作为再生骨料（DWRA）并加入二氧化硅气凝胶来配制低碳、气凝胶增强的砌体砂浆来解决消防安全和碳减排问题，并且据我们所知，首次对DWRA气凝胶耐火砌体砂浆进行了系统评估。0-30 %气凝胶的混合物分别在200°C、400°C、600°C和800°C下进行火灾模拟实验，然后在环境温度下进行测试。气凝胶的加入改善了隔热性能，将导热系数从0.64 W/（m·K）降低到0.39 W/（m·K）。在800℃时，30% %的气凝胶混合物保持了约40% %的抗压强度（对照组为35% %），减少了高达11.1 %的质量损失，并表现出抑制开裂，表明热稳定性得到了改善。经济环境评价表明，DWAMM的材料成本从70 ~ 671美元/m³ ，但仍低于商用气凝胶砂浆（≈795.3美元/m³），其二氧化碳排放量为734.6 ~ 811.3 kg CO₂/m³ ，比商用气凝胶保温砂浆（890 kg CO₂-eq/m³）低8.8 ~ 17.5 %。综合表征，包括质量损失、导热系数（GB/T 10294-2008）、抗压强度（JGJ/T 70-2009）、抗折强度（GB/T 17671-2021）、超声脉冲速度（ASTM C597-16）和扫描电镜，证实了20 - 30% %气凝胶混合物在耐火、隔热、经济性能和减碳之间取得了良好的平衡，支持低碳耐火建筑围护结构的发展。

{"title":"Low-carbon fire-resistant masonry mortar incorporating decoration waste recycled aggregates for sustainable building envelopes","authors":"Pinghua Zhu , Tianqi Tao , Hongyun Chen , Chunhong Chen , Feifei Jiang , Hui Liu , Xiancui Yan , Lei Yang","doi":"10.1016/j.conbuildmat.2025.145065","DOIUrl":"10.1016/j.conbuildmat.2025.145065","url":null,"abstract":"<div><div>The construction industry is one of the largest energy consumers and a significant source of carbon emissions. Energy-efficient building envelopes are essential, but conventional insulation materials like expanded polystyrene (EPS) pose serious fire risks and emit CO₂ when burned. This study addresses fire safety and carbon reduction by using decoration waste as recycled aggregates (DWRA) and incorporating silica aerogel to formulate a low-carbon, aerogel-enhanced masonry mortar, and, to the best of our knowledge, provides the first systematic evaluation of DWRA–aerogel fire-resistant masonry mortar. Mixtures with 0–30 % aerogel were subjected to fire-simulation experiments at 200 °C, 400 °C, 600 °C, and 800 °C, followed by testing at ambient temperature. The incorporation of aerogel improved thermal insulation, reducing thermal conductivity from 0.64 W/(m·K) to 0.39 W/(m·K). At 800 °C, the 30 % aerogel mix retained about 40 % of compressive strength (compared with 35 % for the control), reduced mass loss by up to 11.1 %, and exhibited suppressed cracking, indicating improved thermal stability. A cradle-to-gate economic and environmental assessment shows that the material cost of DWAMM increases from 70 to 671 USD/m³ but remains below that of commercial aerogel mortar (≈795.3 USD/m³), while its CO₂ emissions of 734.6–811.3 kg CO₂/m³ are 8.8–17.5 % lower than those of commercial aerogel insulating mortar (890 kg CO₂-eq/m³). Comprehensive characterization, including mass loss, thermal conductivity (GB/T 10294–2008), compressive strength (JGJ/T 70–2009), flexural strength (GB/T 17671–2021), ultrasonic pulse velocity (ASTM C597–16), and scanning electron microscopy, confirms that the 20–30 % aerogel mixes achieve a favorable balance among fire resistance, thermal insulation, economic performance, and embodied-carbon reduction, supporting the development of low-carbon fire-resistant building envelopes.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"507 ","pages":"Article 145065"},"PeriodicalIF":8.0,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145883271","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}

引用次数: 0

Design and optimization of eco-friendly cement grout modified with bagasse ash and nano-silica for semi-flexible pavements using RSM 半柔性路面采用RSM改性蔗渣灰和纳米二氧化硅环保型水泥浆料的设计与优化

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-03 DOI: 10.1016/j.conbuildmat.2025.144988

Muhammad Ahmad Sajid , Muhammad Imran Khan , Inamullah Khan , Omar Eid Almutairi

This study explores sustainable cementitious grouts for semi-flexible pavements by replacing Ordinary Portland Cement (OPC) with Sugarcane Bagasse Ash (SBA) (0–20 %) and 1 % Nano-Silica (NS). The flow and compressive strength of cementitious grouts were assessed using the ASTM flow cone and compression testing machine (CTM), while the microstructural properties were examined using SEM and EDX. Results showed that optimized grouts with 10 % SBA and 1 % NS, along with 1 % superplasticizer (SP), improved strength, flow, and shrinkage resistance. The reference grout (0.35 w/c, 1 % SP) met ASTM flow requirements, while SBA-NS-modified grouts improved compressive strength by 18 % after 28 days of curing. Higher w/c ratios reduced strength and flow-out time. Microstructural analysis confirmed densification, reduced porosity, and enhanced phase formation due to SBA-NS interactions. Response Surface Methodology (RSM) and ANOVA validated results strongly agree with predictive models. This study establishes SBA as a viable supplementary material, enhancing grout durability while promoting sustainable construction by reducing cement usage, utilizing waste, and contributing to eco-friendly infrastructure development.

本研究通过用蔗渣灰（SBA）（0 - 20% %）和1 %纳米二氧化硅（NS）取代普通波特兰水泥（OPC）来探索半柔性路面的可持续胶凝注浆。采用ASTM流动锥和压缩试验机（CTM）对胶凝注浆的流动强度和抗压强度进行了评估，并用SEM和EDX对其微观结构特性进行了检测。结果表明：添加 % SBA、 % NS、 %高效减水剂（SP）后，浆液的强度、流动性和抗缩性均有所提高。参考浆液（0.35 w/c, 1 % SP）满足ASTM流动要求，而sba - ns改性浆液在养护28天后抗压强度提高了18 %。较高的w/c比降低了强度和流出时间。显微结构分析证实了SBA-NS相互作用导致的致密化、孔隙率降低和相形成增强。响应面法（RSM）和方差分析验证的结果与预测模型非常吻合。本研究将SBA作为一种可行的补充材料，通过减少水泥使用量、利用废物和促进生态友好型基础设施发展，提高浆液耐久性，同时促进可持续建筑。

{"title":"Design and optimization of eco-friendly cement grout modified with bagasse ash and nano-silica for semi-flexible pavements using RSM","authors":"Muhammad Ahmad Sajid , Muhammad Imran Khan , Inamullah Khan , Omar Eid Almutairi","doi":"10.1016/j.conbuildmat.2025.144988","DOIUrl":"10.1016/j.conbuildmat.2025.144988","url":null,"abstract":"<div><div>This study explores sustainable cementitious grouts for semi-flexible pavements by replacing Ordinary Portland Cement (OPC) with Sugarcane Bagasse Ash (SBA) (0–20 %) and 1 % Nano-Silica (NS). The flow and compressive strength of cementitious grouts were assessed using the ASTM flow cone and compression testing machine (CTM), while the microstructural properties were examined using SEM and EDX. Results showed that optimized grouts with 10 % SBA and 1 % NS, along with 1 % superplasticizer (SP), improved strength, flow, and shrinkage resistance. The reference grout (0.35 w/c, 1 % SP) met ASTM flow requirements, while SBA-NS-modified grouts improved compressive strength by 18 % after 28 days of curing. Higher w/c ratios reduced strength and flow-out time. Microstructural analysis confirmed densification, reduced porosity, and enhanced phase formation due to SBA-NS interactions. Response Surface Methodology (RSM) and ANOVA validated results strongly agree with predictive models. This study establishes SBA as a viable supplementary material, enhancing grout durability while promoting sustainable construction by reducing cement usage, utilizing waste, and contributing to eco-friendly infrastructure development.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"507 ","pages":"Article 144988"},"PeriodicalIF":8.0,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145923004","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}

引用次数: 0

The effect of high temperature, freeze-thaw cycles, and chloride attack on the smart properties of CNTs modified cement-based composites 高温、冻融循环和氯化物侵蚀对CNTs改性水泥基复合材料智能性能的影响

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-03 DOI: 10.1016/j.conbuildmat.2025.145098

Yangchen Xu , Shuting Du , Yi Zhao , Lei Zhang , Kai Li , Shufeng Li , Guohua Xing

CNTs modified cement-based composites (CNTs/CC) have shown great potential in the field of concrete structure health monitoring due to their excellent mechanical and smart (piezoresistive, tensile sensitive, and flexural sensitive) properties. However, there are significant challenges to the performance stability and reliability of CNTs/CC under special environments such as high temperature, freeze-thaw, and chloride attack. Therefore, the conductivity and smart properties of CNTs/CC were studied under high temperature (200℃, 400℃, and 600℃), freeze-thaw cycles (50 times, 100 times, and 150 times), and chloride attack (30 d, 90 d, and 180 d) treatments. The results showed that the mechanical properties of CNTs/CC deteriorated after high temperature and freeze-thaw cycles, but the smart properties were improved. After the high temperature of 600°C, the frictional change in resistivity (FCR) and strain sensitivity of CNTs/CC increased significantly, with the FCR increasing from 22.37 % to 44.89 % at room temperature (25°C) under 10 MPa cyclic compressive loading, and the strain sensitivity also increasing from 829.9 to 1994.62. With the increase of freeze-thaw cycles, the FCR of CNTs/CC significantly increases under compressive, tensile, and flexural loads. Compared to the uneroded composites, the microstructure of CNTs/CC was denser and the pore size distribution was more refined after 180 d of chloride attack, which led to an improvement in the mechanical properties, but had less effect on the smart properties. The related outcomes fundamentally reveal the performance adaptability of CNTs/CC in special environments and promote the practical application of CNTs/CC in the health monitoring of concrete structures.

CNTs改性水泥基复合材料（CNTs/CC）由于其优异的力学和智能（压阻、拉伸敏感和弯曲敏感）性能，在混凝土结构健康监测领域显示出巨大的潜力。然而，在高温、冻融和氯化物侵蚀等特殊环境下，CNTs/CC的性能稳定性和可靠性面临重大挑战。因此，研究了高温（200℃、400℃和600℃）、冻融循环（50次、100次和150次）和氯化物侵蚀（30 d、90 d和180 d）处理下CNTs/CC的电导率和智能性能。结果表明：高温和冻融循环后，CNTs/CC的力学性能下降，但智能性能得到改善；高温600℃后，CNTs/CC的摩擦电阻率变化（FCR）和应变灵敏度显著增加，10 MPa循环压缩载荷下，室温（25℃）下的FCR从22.37 %增加到44.89 %，应变灵敏度也从829.9增加到1994.62。随着冻融循环次数的增加，CNTs/CC在压缩、拉伸和弯曲载荷下的FCR显著增加。与未受侵蚀的复合材料相比，经过氯侵蚀180 d后，CNTs/CC的微观结构更加致密，孔径分布更加细化，力学性能得到改善，但对智能性能的影响较小。相关结果从根本上揭示了CNTs/CC在特殊环境下的性能适应性，促进了CNTs/CC在混凝土结构健康监测中的实际应用。

{"title":"The effect of high temperature, freeze-thaw cycles, and chloride attack on the smart properties of CNTs modified cement-based composites","authors":"Yangchen Xu , Shuting Du , Yi Zhao , Lei Zhang , Kai Li , Shufeng Li , Guohua Xing","doi":"10.1016/j.conbuildmat.2025.145098","DOIUrl":"10.1016/j.conbuildmat.2025.145098","url":null,"abstract":"<div><div>CNTs modified cement-based composites (CNTs/CC) have shown great potential in the field of concrete structure health monitoring due to their excellent mechanical and smart (piezoresistive, tensile sensitive, and flexural sensitive) properties. However, there are significant challenges to the performance stability and reliability of CNTs/CC under special environments such as high temperature, freeze-thaw, and chloride attack. Therefore, the conductivity and smart properties of CNTs/CC were studied under high temperature (200℃, 400℃, and 600℃), freeze-thaw cycles (50 times, 100 times, and 150 times), and chloride attack (30 d, 90 d, and 180 d) treatments. The results showed that the mechanical properties of CNTs/CC deteriorated after high temperature and freeze-thaw cycles, but the smart properties were improved. After the high temperature of 600°C, the frictional change in resistivity (FCR) and strain sensitivity of CNTs/CC increased significantly, with the FCR increasing from 22.37 % to 44.89 % at room temperature (25°C) under 10 MPa cyclic compressive loading, and the strain sensitivity also increasing from 829.9 to 1994.62. With the increase of freeze-thaw cycles, the FCR of CNTs/CC significantly increases under compressive, tensile, and flexural loads. Compared to the uneroded composites, the microstructure of CNTs/CC was denser and the pore size distribution was more refined after 180 d of chloride attack, which led to an improvement in the mechanical properties, but had less effect on the smart properties. The related outcomes fundamentally reveal the performance adaptability of CNTs/CC in special environments and promote the practical application of CNTs/CC in the health monitoring of concrete structures.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"507 ","pages":"Article 145098"},"PeriodicalIF":8.0,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145923003","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}

引用次数: 0

Mesoscale THMS coupling analysis of early-age concrete cracking: Role of heterogeneity and interfacial transition zone 早期混凝土开裂的中尺度THMS耦合分析：非均质性和界面过渡区的作用

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-03 DOI: 10.1016/j.conbuildmat.2025.145084

Renlong Wang , Zheng Si , Lingzhi Huang , Jiaxin Wang , Penglong Zhao , Yulong Zhang , Xiaorui Liu , An Yang

Early-age concrete cracking, driven by the complex interplay of thermal, hydration, moisture, and stress (THMS) fields, significantly compromises the durability of concrete structures. Conventional models often oversimplify concrete as a homogeneous material and fail to capture this complexity. To address this limitation, this study develops a mesoscopic-scale THMS coupling model that explicitly accounts for the heterogeneity of aggregates, mortar, and the interfacial transition zone (ITZ), each possessing distinct constitutive properties. The governing equations are discretized and solved using the finite element method (FEM), enabling high-precision simulation of multiphysics interactions. The model is rigorously validated against macroscopic experiments, with simulations demonstrating close agreement with measured data—accurately replicating the internal temperature increase (peaking at 27.2–27.6 °C between 72 and 96 h) and the humidity decrease (from 0.98 to 0.71–0.80 after 672 h). Combined with microhardness testing and scanning electron microscopy (SEM) analysis of the microstructural evolution of the ITZ, a mechanistic explanation for the simulation results is provided: within 3–6 days, the internal stress exceeds the tensile strength, with the cracking risk index surpassing 0.7. Microhardness tests indicate that the mechanical properties of the ITZ are significantly weaker than those of the mortar matrix at this stage. Further analysis demonstrates that a higher aggregate content intensifies restraint stress, thereby accelerating the cracking process. The proposed model offers a powerful tool for predicting cracking risk and optimizing curing strategies, contributing to the enhancement of structural durability.

早期混凝土开裂是由热、水化、水分和应力（THMS）场的复杂相互作用驱动的，严重损害了混凝土结构的耐久性。传统的模型往往将混凝土简单化，认为它是一种同质材料，无法捕捉到这种复杂性。为了解决这一限制，本研究开发了一种介观尺度的THMS耦合模型，该模型明确考虑了骨料、砂浆和界面过渡区（ITZ）的非均质性，每种都具有不同的本构性质。采用有限元法对控制方程进行离散化求解，实现了多物理场相互作用的高精度模拟。该模型通过宏观实验进行了严格验证，模拟结果与测量数据非常吻合，准确地复制了内部温度升高（在72至96 h之间达到27.2-27.6°C的峰值）和湿度降低（在672 h之后从0.98降至0.71-0.80）。结合显微硬度测试和扫描电镜（SEM）对ITZ微观组织演变的分析，对模拟结果提供了机理解释：在3-6天内，内应力超过抗拉强度，开裂风险指数超过0.7。显微硬度测试表明，在这一阶段，ITZ的力学性能明显弱于砂浆基体。进一步分析表明，较高的骨料含量会加剧约束应力，从而加速开裂过程。该模型为预测裂缝风险和优化养护策略提供了有力的工具，有助于提高结构的耐久性。

{"title":"Mesoscale THMS coupling analysis of early-age concrete cracking: Role of heterogeneity and interfacial transition zone","authors":"Renlong Wang , Zheng Si , Lingzhi Huang , Jiaxin Wang , Penglong Zhao , Yulong Zhang , Xiaorui Liu , An Yang","doi":"10.1016/j.conbuildmat.2025.145084","DOIUrl":"10.1016/j.conbuildmat.2025.145084","url":null,"abstract":"<div><div>Early-age concrete cracking, driven by the complex interplay of thermal, hydration, moisture, and stress (THMS) fields, significantly compromises the durability of concrete structures. Conventional models often oversimplify concrete as a homogeneous material and fail to capture this complexity. To address this limitation, this study develops a mesoscopic-scale THMS coupling model that explicitly accounts for the heterogeneity of aggregates, mortar, and the interfacial transition zone (ITZ), each possessing distinct constitutive properties. The governing equations are discretized and solved using the finite element method (FEM), enabling high-precision simulation of multiphysics interactions. The model is rigorously validated against macroscopic experiments, with simulations demonstrating close agreement with measured data—accurately replicating the internal temperature increase (peaking at 27.2–27.6 °C between 72 and 96 h) and the humidity decrease (from 0.98 to 0.71–0.80 after 672 h). Combined with microhardness testing and scanning electron microscopy (SEM) analysis of the microstructural evolution of the ITZ, a mechanistic explanation for the simulation results is provided: within 3–6 days, the internal stress exceeds the tensile strength, with the cracking risk index surpassing 0.7. Microhardness tests indicate that the mechanical properties of the ITZ are significantly weaker than those of the mortar matrix at this stage. Further analysis demonstrates that a higher aggregate content intensifies restraint stress, thereby accelerating the cracking process. The proposed model offers a powerful tool for predicting cracking risk and optimizing curing strategies, contributing to the enhancement of structural durability.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"507 ","pages":"Article 145084"},"PeriodicalIF":8.0,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145883268","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}

引用次数: 0

Spalling resistance of SUHPC based on PC-CAC-C$ at elevated temperatures: Role of whiskers and steel fibers 基于pc - c - c $的SUHPC高温抗剥落性能：晶须和钢纤维的作用

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-03 DOI: 10.1016/j.conbuildmat.2025.145100

Jia He , Yanshuo Liu , Xuan Ling , Huayi Wang , Zhiyi Tang , Zhengrui Chen , Qingliang Yu

Sprayed ultra-high-performance concrete (SUHPC) holds great promise for structural repair and complex construction due to its exceptional strength and durability. However, conventional Portland cement-based SUHPC is highly susceptible to explosive spalling at elevated temperatures. This study develops a spalling-resistant SUHPC by introducing a Portland cement–calcium aluminate cement–gypsum (PC–CAC–C$) ternary system, reinforced with calcium sulfate whiskers (CSW) and steel fibers. The results reveal that the ternary system retained thermally stable crystalline phases (Al₂O₃, C₁₂A₇, wollastonite, CA, CA₂) up to 1000 °C, conferring superior phase stability compared with the PC-based system. At the microstructural level, the ternary system increased the fraction of capillary porosity. The incorporation of CSW promoted the accumulation of hydration products within the interfacial transition zone (ITZ), which refined the CSW–matrix interface and led to improved flexural performance. Notably, benefiting from the synergistic effect of CSW and steel fibers, the ternary system facilitated the formation of continuous and uniformly distributed vapor-release channels, which effectively suppressed explosive spalling and enabled SUHPC to retain a high residual compressive strength of 45.8 MPa and a flexural strength of 7.4 MPa even after exposure to 1000 °C. This study provides an effective strategy for enhancing the high-temperature resistance of SUHPC, thereby broadening its potential for durable structural repair and fire-resilient applications.

喷射高性能混凝土（SUHPC）由于其优异的强度和耐久性，在结构修复和复杂建筑中具有很大的前景。然而，传统的波特兰水泥基SUHPC在高温下极易发生爆炸剥落。本研究通过引入波特兰水泥-铝酸钙水泥-石膏（pc - c - c - $）三元体系，用硫酸钙晶须（CSW）和钢纤维增强，开发了一种抗剥落的SUHPC。结果表明，该三元体系在1000℃下仍保持热稳定的晶相（Al₂O₃，C₁₂A₇，硅灰石，CA, CA₂），与基于pc的体系相比，具有更好的相稳定性。在微观结构水平上，三元体系增加了毛管孔隙率。CSW的加入促进了界面过渡区（ITZ）水化产物的积累，从而细化了CSW -基质界面，提高了抗弯性能。值得注意的是，得益于CSW和钢纤维的协同作用，该体系有利于形成连续且均匀分布的蒸汽释放通道，有效抑制了爆炸剥落，使SUHPC在1000℃下仍能保持45.8 MPa的残余抗压强度和7.4 MPa的残余抗折强度。该研究为提高SUHPC的耐高温性能提供了有效的策略，从而扩大了其在耐用结构修复和防火应用方面的潜力。

{"title":"Spalling resistance of SUHPC based on PC-CAC-C$ at elevated temperatures: Role of whiskers and steel fibers","authors":"Jia He , Yanshuo Liu , Xuan Ling , Huayi Wang , Zhiyi Tang , Zhengrui Chen , Qingliang Yu","doi":"10.1016/j.conbuildmat.2025.145100","DOIUrl":"10.1016/j.conbuildmat.2025.145100","url":null,"abstract":"<div><div>Sprayed ultra-high-performance concrete (SUHPC) holds great promise for structural repair and complex construction due to its exceptional strength and durability. However, conventional Portland cement-based SUHPC is highly susceptible to explosive spalling at elevated temperatures. This study develops a spalling-resistant SUHPC by introducing a Portland cement–calcium aluminate cement–gypsum (PC–CAC–C$) ternary system, reinforced with calcium sulfate whiskers (CSW) and steel fibers. The results reveal that the ternary system retained thermally stable crystalline phases (Al₂O₃, C₁₂A₇, wollastonite, CA, CA₂) up to 1000 °C, conferring superior phase stability compared with the PC-based system. At the microstructural level, the ternary system increased the fraction of capillary porosity. The incorporation of CSW promoted the accumulation of hydration products within the interfacial transition zone (ITZ), which refined the CSW–matrix interface and led to improved flexural performance. Notably, benefiting from the synergistic effect of CSW and steel fibers, the ternary system facilitated the formation of continuous and uniformly distributed vapor-release channels, which effectively suppressed explosive spalling and enabled SUHPC to retain a high residual compressive strength of 45.8 MPa and a flexural strength of 7.4 MPa even after exposure to 1000 °C. This study provides an effective strategy for enhancing the high-temperature resistance of SUHPC, thereby broadening its potential for durable structural repair and fire-resilient applications.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"507 ","pages":"Article 145100"},"PeriodicalIF":8.0,"publicationDate":"2026-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145883204","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}

引用次数: 0

Durability of seawater and sea sand concrete under combined carbonation and chloride attack: A numerical study 海水和海砂混凝土在碳化和氯化物联合侵蚀下耐久性的数值研究

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-02 DOI: 10.1016/j.conbuildmat.2025.144519

Le-rong Wang , Liang-yu Tong , Jian-Guo Dai , Qing-xiang Xiong , Yi-fei Chen , Zhi-qi Wang , Qing-feng Liu

The utilization of seawater and sea sand concrete presents a promising alternative to address the shortage of freshwater and river sand. To date, however, limited research has been conducted on the long-term performance of seawater and sea sand concrete. This study establishes a novel model for predicting the degradation of seawater and sea sand concrete accounting for the interactions between premixed chlorides, external chloride ingress, and carbonation for the first time. This framework integrates the accelerated hydration induced by premixed chloride, the carbonation process affected by environmental factors, and the transport of chloride influenced by carbonation. Porosity serves as a critical intermediate variable, coupling the modelling framework together. Validation of this model against three experimental datasets demonstrates its prediction accuracy. After that, the comprehensive parametric analysis reveals that the detrimental impacts of incorporating seawater and sea sand significantly outweigh their potential benefits. The presence of 200

mol / m^{3}

initial chloride has been shown to increase the chloride accumulation rate at a depth of 30 mm of concrete by approximately 65 %. Carbonation accelerates chloride transport when porosity reduction is less than 10 %, an effect amplified by seawater and sea sand addition. Increasing relative humidity accelerates chloride transport but suppresses carbonation progression, necessitating context-dependent evaluation. The present study aims to establish a robust analytical framework for assessing the durability of seawater and sea sand concrete under combined carbonation and chloride attack.

利用海水和海砂混凝土是解决淡水和河砂短缺的一种有希望的替代方案。然而，迄今为止，对海水和海砂混凝土长期性能的研究还很有限。本研究首次建立了一种新的模型，用于预测海水和海砂混凝土的降解，该模型考虑了预混氯化物、外部氯化物进入和碳化之间的相互作用。该框架整合了预混合氯离子诱导的加速水化、受环境因素影响的碳化过程以及受碳化作用影响的氯离子转运。孔隙度作为一个关键的中间变量，将建模框架耦合在一起。在三个实验数据集上验证了该模型的预测精度。之后，综合参数分析表明，海水和海砂掺入的不利影响明显大于其潜在效益。200mol/m3初始氯化物的存在已被证明可使混凝土深度为30mm处的氯化物积累速率增加约65%。当孔隙度降低小于10%时，碳化作用加速了氯离子的输运，海水和海砂的加入放大了这一作用。增加相对湿度会加速氯离子的运输，但会抑制碳酸化进程，因此需要进行环境相关的评估。本研究旨在建立一个强大的分析框架，以评估海水和海砂混凝土在碳化和氯化物联合侵蚀下的耐久性。

{"title":"Durability of seawater and sea sand concrete under combined carbonation and chloride attack: A numerical study","authors":"Le-rong Wang , Liang-yu Tong , Jian-Guo Dai , Qing-xiang Xiong , Yi-fei Chen , Zhi-qi Wang , Qing-feng Liu","doi":"10.1016/j.conbuildmat.2025.144519","DOIUrl":"10.1016/j.conbuildmat.2025.144519","url":null,"abstract":"<div><div>The utilization of seawater and sea sand concrete presents a promising alternative to address the shortage of freshwater and river sand. To date, however, limited research has been conducted on the long-term performance of seawater and sea sand concrete. This study establishes a novel model for predicting the degradation of seawater and sea sand concrete accounting for the interactions between premixed chlorides, external chloride ingress, and carbonation for the first time. This framework integrates the accelerated hydration induced by premixed chloride, the carbonation process affected by environmental factors, and the transport of chloride influenced by carbonation. Porosity serves as a critical intermediate variable, coupling the modelling framework together. Validation of this model against three experimental datasets demonstrates its prediction accuracy. After that, the comprehensive parametric analysis reveals that the detrimental impacts of incorporating seawater and sea sand significantly outweigh their potential benefits. The presence of 200<span><math><mrow><mi>mol</mi><mo>/</mo><msup><mrow><mi>m</mi></mrow><mrow><mn>3</mn></mrow></msup></mrow></math></span> initial chloride has been shown to increase the chloride accumulation rate at a depth of 30 mm of concrete by approximately 65 %. Carbonation accelerates chloride transport when porosity reduction is less than 10 %, an effect amplified by seawater and sea sand addition. Increasing relative humidity accelerates chloride transport but suppresses carbonation progression, necessitating context-dependent evaluation. The present study aims to establish a robust analytical framework for assessing the durability of seawater and sea sand concrete under combined carbonation and chloride attack.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"507 ","pages":"Article 144519"},"PeriodicalIF":8.0,"publicationDate":"2026-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145882727","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}

引用次数: 0

Cl- transport characteristics within nano-marine concrete under bending load coupled with dry and wet cycles 干湿循环下弯曲荷载耦合作用下纳米海工混凝土中Cl-输运特性

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-02 DOI: 10.1016/j.conbuildmat.2025.145036

Maohua Zhang , Danan Ma , Daocheng Zhou

To reveal the evolution of the convection zone in nano-marine concrete under the coupling effect of drying-wetting cycles (DWC) and flexural loads (DWL), the indoor coupling experiment was conducted to analyze the Cl^- distribution within nano-marine concrete in this study. The mechanism of the influence of nanoparticle admixture (A), stress levels (σ), and the corrosive time (t) on the peak content of Cl^- (C_max) and the depth of the convection zone (∆x) within each concrete was investigated. Additionally, the deterioration mechanism of nano-maritime concrete properties was explored. Subsequently, the optimal ratios of nanoparticle admixture for marine concrete were proposed. Advanced techniques, including electron microprobe analysis (EMPA), backscattered electron microscopy (BSEM), mercury intrusion porosimetry (MIP), X-ray diffraction (XRD), and differential thermal gravimetry (DTG), were applied to characterise the microstructure of the interfacial transition zone (ITZ). Results showed that C_max, ∆x and Cl^- diffusion coefficient (D_f) in the compression zone (C) decrease and then increase with increasing load stress level (σ) and nanoparticle content (A), and C_max, ∆x and D_f in the tensile zone (T) increase with increasing σ. The optimal nano-particle content was 2 %. The mode of Cl^- transport is gradually changing from ‘convection-diffusion’ to ‘diffusion’. Furthermore, the Cl^- diffusion coefficient (D_f) was negatively correlated with t and positively correlated with σ, with a significant effect of nanoparticles. Microstructural analysis showed that the porosity and pore diameter of marine concrete initially decreased and then increased. Cl^- in concrete primarily travelled along microcracks, with distinct penetration traces. The admixture of nano-SiO₂ and nano-Fe₃O₄ refined the pores, promoted the formation of hydration products such as C-S-H and C-F-H, and improved the densification and adhesion of the concrete's ITZ, which significantly diminished the C_max and ∆x, hindering the development of convective zones.

为了揭示干湿循环（DWC）和弯曲荷载（DWL）耦合作用下纳米海工混凝土对流区演化规律，本研究采用室内耦合试验对纳米海工混凝土内部Cl-分布进行了分析。研究了纳米颗粒掺量(A)、应力水平（σ）和腐蚀时间(t)对各混凝土内部Cl-峰值含量（Cmax）和对流区深度（∆x）的影响机理。此外，还探讨了纳米海洋混凝土性能劣化机理。在此基础上，提出了海洋混凝土中纳米颗粒掺合料的最佳配比。采用电子探针分析（EMPA）、背散射电子显微镜（BSEM）、压汞法（MIP）、x射线衍射（XRD）和差热重法（DTG）等先进技术对界面过渡区（ITZ）的微观结构进行了表征。结果表明：压缩区(C)的Cmax、∆x和Cl-扩散系数（Df）随着载荷应力水平（σ）和纳米颗粒含量(A)的增大先减小后增大；拉伸区(T)的Cmax、∆x和Df随着σ的增大而增大；最佳纳米颗粒含量为2 %。Cl-输运模式正逐渐由“对流-扩散”向“扩散”转变。Cl-扩散系数Df与t呈负相关，与σ呈正相关，其中纳米颗粒的影响显著。微观结构分析表明，海相混凝土的孔隙率和孔径先减小后增大。混凝土中的Cl-主要沿着微裂缝传播，具有明显的渗透痕迹。纳米sio2和纳米fe3o4的掺入细化了孔隙，促进了C-S-H和C-F-H等水化产物的形成，提高了混凝土ITZ的密实性和附着力，显著降低了Cmax和∆x，阻碍了对流区的发展。

{"title":"Cl- transport characteristics within nano-marine concrete under bending load coupled with dry and wet cycles","authors":"Maohua Zhang , Danan Ma , Daocheng Zhou","doi":"10.1016/j.conbuildmat.2025.145036","DOIUrl":"10.1016/j.conbuildmat.2025.145036","url":null,"abstract":"<div><div>To reveal the evolution of the convection zone in nano-marine concrete under the coupling effect of drying-wetting cycles (DWC) and flexural loads (DWL), the indoor coupling experiment was conducted to analyze the Cl<sup>-</sup> distribution within nano-marine concrete in this study. The mechanism of the influence of nanoparticle admixture (<em>A</em>), stress levels (σ), and the corrosive time (t) on the peak content of Cl<sup>-</sup> (C<sub><em>max</em></sub>) and the depth of the convection zone (∆<em>x</em>) within each concrete was investigated. Additionally, the deterioration mechanism of nano-maritime concrete properties was explored. Subsequently, the optimal ratios of nanoparticle admixture for marine concrete were proposed. Advanced techniques, including electron microprobe analysis (EMPA), backscattered electron microscopy (BSEM), mercury intrusion porosimetry (MIP), X-ray diffraction (XRD), and differential thermal gravimetry (DTG), were applied to characterise the microstructure of the interfacial transition zone (ITZ). Results showed that C<sub><em>max</em></sub>, ∆<em>x</em> and Cl<sup>-</sup> diffusion coefficient (D<sub><em>f</em></sub>) in the compression zone (C) decrease and then increase with increasing load stress level (σ) and nanoparticle content (A), and C<sub>max</sub>, ∆<em>x</em> and D<sub><em>f</em></sub> in the tensile zone (T) increase with increasing σ. The optimal nano-particle content was 2 %. The mode of Cl<sup>-</sup> transport is gradually changing from ‘convection-diffusion’ to ‘diffusion’. Furthermore, the Cl<sup>-</sup> diffusion coefficient (D<sub><em>f</em></sub>) was negatively correlated with t and positively correlated with σ, with a significant effect of nanoparticles. Microstructural analysis showed that the porosity and pore diameter of marine concrete initially decreased and then increased. Cl<sup>-</sup> in concrete primarily travelled along microcracks, with distinct penetration traces. The admixture of nano-SiO<sub>2</sub> and nano-Fe<sub>3</sub>O<sub>4</sub> refined the pores, promoted the formation of hydration products such as C-S-H and C-F-H, and improved the densification and adhesion of the concrete's ITZ, which significantly diminished the C<sub><em>max</em></sub> and ∆<em>x,</em> hindering the development of convective zones.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"507 ","pages":"Article 145036"},"PeriodicalIF":8.0,"publicationDate":"2026-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145883183","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}

引用次数: 0