Construction and Building Materials最新文献_第5页

Preparation and performance evaluation of epoxy resin-based binders for rubber-aggregate pavements 橡胶集料路面用环氧树脂基粘结剂的制备及性能评价

IF 7.4 1区工程技术

Construction and Building Materials Pub Date : 2025-05-30 DOI: 10.1016/j.conbuildmat.2025.141870

Pinxue Zhao, Biao Ma, Jiayun Xu, Wei Si

{"title":"Preparation and performance evaluation of epoxy resin-based binders for rubber-aggregate pavements","authors":"Pinxue Zhao, Biao Ma, Jiayun Xu, Wei Si","doi":"10.1016/j.conbuildmat.2025.141870","DOIUrl":"10.1016/j.conbuildmat.2025.141870","url":null,"abstract":"<div><div>Rubber aggregate pavements consist of rubber particles and polymer binders, providing a solution for sustainable reuse of waste tires. The performance of polymer binder-rubber pavement is unsatisfactory owing to inadequate mechanical compatibility between the polymer binder and rubber. To address this issue, this study developed a high-performance epoxy resin-based binder. The binder comprises diglycidyl ether of bisphenol A as the matrix, polypropylene glycol diglycidyl ether as the diluent, trimethylolpropane tris (3-mercaptopropionate) as the curing agent, and 2,4,6-tris (dimethylaminomethyl) phenol as the catalyst. The resin composite (DTPP) with tailored rubbery state temperature ranges were synthesized by adjusting the diluent content. The compositions, curing behavior, thermal stability of the resin-binder, and the mechanical compatibility between the binder and rubber aggregates were comprehensively assessed using differential scanning calorimetry, Fourier transform infrared spectroscopy, thermogravimetric analyzer, and dynamic mechanical analyzer. The results showed that DTPP has a reaction activation energy below 40 kJ/mol, allowing sufficient curing at low temperatures. A negative linear correlation was identified between the diluent content and the glass transition temperature (<em>T</em>g) of DTPP. By adjusting the diluent content, DTPP with Tg values ranging from −24.1 °C to 16.1 °C can be precisely synthesized, thereby adjusting the temperature range of their high elastic mechanical states. Dynamic mechanical analysis demonstrated that at 20 °C higher than the glass transition temperature, both DTPP and rubber achieve stable elastic rubbery states, exhibiting similar compressive modulus and relaxation properties. The developed DTPP exhibited satisfactory mechanical compatibility with rubber aggregates across a broad temperature range, providing a novel solution to the durability challenges of rubber aggregate pavements.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"486 ","pages":"Article 141870"},"PeriodicalIF":7.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144166208","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

IF 7.4 1区工程技术

Construction and Building Materials Pub Date : 2025-05-30 DOI: 10.1016/j.conbuildmat.2025.142018

Guanghui Gao , Hui Xu , Jiuwen Bao , Yanru Wang , Yifei Cui , Qiang Song , Jianwei Sun

{"title":"Durability-related properties of alkali-activated recycled aggregate concrete: Effect of alkali equivalent, recycled coarse aggregate replacement rate and slag content","authors":"Guanghui Gao , Hui Xu , Jiuwen Bao , Yanru Wang , Yifei Cui , Qiang Song , Jianwei Sun","doi":"10.1016/j.conbuildmat.2025.142018","DOIUrl":"10.1016/j.conbuildmat.2025.142018","url":null,"abstract":"<div><div>This study investigated the durability-related properties of alkali-activated recycled aggregate concrete (AA-RAC) incorporating fly ash and slag. The chloride transport, capillary absorption and freeze-thaw cycles tests of AA-RAC with various dosages were further conducted. The compressive strength tests for a series of specimens and their microstructural observations were carried out. The optimizing proportions combination of the alkali equivalent, RCA replacement rate and slag content by comprehensively considering the tested indicators was finally determined. The results indicate that the specimen with 10 % alkali equivalent, no RCA and 40 % slag content (C10-R0) generally exhibited the excellent mechanical and durability properties, and on the contrary, the specimen with 8 % alkali equivalent and 100 % RCAs (A8-R100) showed the poorest performance. The addition of slag significantly promotes the hydration of fly ash, improving the mechanical and durability properties of AA-RAC. Increasing alkali equivalent and slag content effectively decreases the water absorption rate and improves frost resistance of AA-RAC, but chloride diffusion coefficient and its penetration depth increase with an increase of RCA replacement rate. It is preferable to set up compatibility with high slag content, high alkali equivalent, and low RCA replacement rate for achieving the optimized durability-related performance, providing scientific justification for its extensive application in the practical engineering.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"486 ","pages":"Article 142018"},"PeriodicalIF":7.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178704","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

Study on the physical and mechanical properties of concrete interfacial transition zones (ITZ) with consideration of positional effects 考虑位置效应的混凝土界面过渡区物理力学性能研究

IF 7.4 1区工程技术

Construction and Building Materials Pub Date : 2025-05-30 DOI: 10.1016/j.conbuildmat.2025.141985

Desheng Yin , Manke Zhang , Bobo Xiong , Shuhua Zhang

{"title":"Study on the physical and mechanical properties of concrete interfacial transition zones (ITZ) with consideration of positional effects","authors":"Desheng Yin , Manke Zhang , Bobo Xiong , Shuhua Zhang","doi":"10.1016/j.conbuildmat.2025.141985","DOIUrl":"10.1016/j.conbuildmat.2025.141985","url":null,"abstract":"<div><div>In this study, the microstructure and mechanical properties of the interfacial transition zone (ITZ) at various locations were examined using electron microscopy, X-ray diffraction, nitrogen adsorption, optical microscopy, microhardness testing, and splitting tensile tests. The mechanisms underlying the differences in ITZ strength across different locations were elucidated, leading to the establishment of a predictive model for ITZ strength that considers pore structure, ITZ location, and water–cement ratio (W/C). Results indicate that an increased W/C corresponds to higher volume of macropores within the ITZ region. Notably, the thickness of the ITZ on the upper surface of aggregates is significantly smaller than that on their lower surfaces. Furthermore, the splitting tensile strength (STS) of the ITZ on the upper surface is considerably lower than that on the lower surface by up to 0.7 MPa. The model developed for predicting ITZ STS effectively incorporates W/Cs and positional factors related to ITZ. The test results demonstrate that position has a considerable impact on ITZ strength characteristics. These insights provide a more nuanced methodology for the subsequent analysis of specific concrete failure mechanisms, while simultaneously offering valuable references to enhance the accuracy and realism of concrete micro-modeling.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"486 ","pages":"Article 141985"},"PeriodicalIF":7.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144166209","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

Inclusive approach for mix proportioning of dry lean concrete based on the experimental study on the effect of cement and coarse aggregate content on strength and abrasion characteristics 基于水泥和粗骨料掺量对干贫混凝土强度和磨损特性影响试验研究的配合比包容性方法

IF 7.4 1区工程技术

Construction and Building Materials Pub Date : 2025-05-30 DOI: 10.1016/j.conbuildmat.2025.141935

Rishikesh Duarah , J. Leon Raj , Amongnaro , Sanjay Deori , Dipak Basumatari

{"title":"Inclusive approach for mix proportioning of dry lean concrete based on the experimental study on the effect of cement and coarse aggregate content on strength and abrasion characteristics","authors":"Rishikesh Duarah , J. Leon Raj , Amongnaro , Sanjay Deori , Dipak Basumatari","doi":"10.1016/j.conbuildmat.2025.141935","DOIUrl":"10.1016/j.conbuildmat.2025.141935","url":null,"abstract":"<div><div>This paper reported the effect of cement and coarse aggregate content on the mechanical and abrasion properties of dry lean concrete (DLC) and proposed design curves for its mix proportioning. DLC has a wide application as a sub-base layer for rigid pavement. 12 DLC mixes were prepared by varying cement content as 150, 180, 210 and 240 kg/m³ and by varying ratio of coarse aggregate-to-total aggregate (CA/TA) ratios as 0.50, 0.60 and 0.70. The strength results such as 7- and 28-day cube and 7-day cylinder compressive strength, 7-day splitting tensile strength and 7-day and 28-day flexural strength increased with increasing cement content and increasing ratio of coarse aggregate-to-total aggregate. The abrasion test showed that mixes with higher cement content and higher coarse aggregate-to-total aggregate ratio exhibited the highest abrasion resistance index. This study has proposed design curves for mix proportioning of DLC based on the correlations between 7- and 28-days cube compressive and flexural strengths for estimating cement, aggregate and water content. The proposed design curves were verified with experimental results and showed a reasonably good prediction.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"486 ","pages":"Article 141935"},"PeriodicalIF":7.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144166206","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

Characterization of interfacial transition zone in compression-cast concrete 压浇筑混凝土界面过渡区的表征

IF 7.4 1区工程技术

Construction and Building Materials Pub Date : 2025-05-30 DOI: 10.1016/j.conbuildmat.2025.141980

Yanshuai Wang, Rou Gang, Rongxin Peng, Yu-Fei Wu

{"title":"Characterization of interfacial transition zone in compression-cast concrete","authors":"Yanshuai Wang, Rou Gang, Rongxin Peng, Yu-Fei Wu","doi":"10.1016/j.conbuildmat.2025.141980","DOIUrl":"10.1016/j.conbuildmat.2025.141980","url":null,"abstract":"<div><div>The interfacial transition zones (ITZs), typically considered as a weak region, significantly impact stress transmission and moisture migration in concrete. To enhance these characteristics, the compression-casting method was employed, and a series of tests were conducted to investigate the microstructural characteristics of ITZs in compression-cast concrete (CCC). Energy dispersive spectroscopy (EDS) and backscattered electron (BSE) image analyses revealed that, compared to normal concrete (NC), CCC exhibits a denser microstructure with fewer pores at the ITZs. Higher compression-casting pressures further densify ITZs and increase the presence of un-hydrated cement particles. Higher w/c ratios were found to increase porosity in ITZs, but the increasing rate gradually diminishes under higher compression-casting pressure. Additionally, nanoindentation tests indicate a 68 % increase in ITZ's elastic modulus of CCC, with its ITZ region being one-tenth size of that in NC. The mortar matrix's elastic modulus rose by 177 %, demonstrating the effectiveness of compression-casting method, and the aggregate's elastic modulus in CCC decreased only 6 % due to compaction-induced microcracks. Moreover, the compressive strength of CCC specimen is 1.07 times that of NC specimen. The compression-casting method effectively improves the mechanical properties of ITZs and mortar matrix, which significantly improves the mechanical properties of concrete from the microscale to the macroscale.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"486 ","pages":"Article 141980"},"PeriodicalIF":7.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178619","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

Sustainable utilization of tailings in permeable material fabrication for sponge city: Synergistic enhancement of mechanical strength and pore structure 海绵城市透水材料制造中尾矿的可持续利用：机械强度与孔隙结构的协同增强

IF 7.4 1区工程技术

Construction and Building Materials Pub Date : 2025-05-30 DOI: 10.1016/j.conbuildmat.2025.142010

Yong Li , Qingchao Zhao , Weiguang Li , Yangge Zhu , Xueliang Li , Peiyao Tang , Yaguang Wang

{"title":"Sustainable utilization of tailings in permeable material fabrication for sponge city: Synergistic enhancement of mechanical strength and pore structure","authors":"Yong Li , Qingchao Zhao , Weiguang Li , Yangge Zhu , Xueliang Li , Peiyao Tang , Yaguang Wang","doi":"10.1016/j.conbuildmat.2025.142010","DOIUrl":"10.1016/j.conbuildmat.2025.142010","url":null,"abstract":"<div><div>Gold tailings (GT) and diamond tailings (DT), which are bulk industrial solid wastes in dire need of disposal, were converted into permeable materials through an eco-efficient method to address the dual challenges of waste management and urban stormwater infrastructure. By integrating GT, DT and kaolin through granulation-sintering optimization, the formulation with a Si/Al ratio of 6.00 (GT/DT = 70:30) achieved a peak flexural strength of 4.11 MPa and a permeability coefficient of 1.77 × 10<sup>−2</sup> cm/s, complying with GB/T 25993–2010. The multiscale microstructural analysis showed that the high temperature induced a phase transition to form a dense aluminumsilicate matrix that provided structural stability. Enhanced crystalline bridges at aggregate contact points formed a skeletal structure with a total porosity of 16.38 %, of which 89.9 % were connected pores. The pore throat characteristics, on the other hand, showed efficient permeability (average pore throat radius: 397.4 μm; coordination number: 2.69). Leaching test confirmed the environmental safety, achieving efficient solidification / stabilization of heavy metals such as As, Ni, Ba, Zn, etc., with a solidification / stabilization rate of more than 90 %, and the complete elimination of cyanide, which complies with Chinese drinking water standards. By substituting 70 %-100 % of conventional natural aggregates with gold/diamond tailings in the permeable material formulation, this approach aligns with circular economy principles while addressing tailings disposal challenges.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"486 ","pages":"Article 142010"},"PeriodicalIF":7.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178703","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

A comparative study of utilizing silica powder and nano-based silica to enhance the properties of MSWIFA-cement based composites 二氧化硅粉与纳米二氧化硅增强mswifa -水泥基复合材料性能的对比研究

IF 7.4 1区工程技术

Construction and Building Materials Pub Date : 2025-05-30 DOI: 10.1016/j.conbuildmat.2025.141987

Kai Lyu , Xinyu Chen , Xiaoyan Liu , Xian Xie , Jinna Shi , Qian Xia , Surendra P. Shah

{"title":"A comparative study of utilizing silica powder and nano-based silica to enhance the properties of MSWIFA-cement based composites","authors":"Kai Lyu , Xinyu Chen , Xiaoyan Liu , Xian Xie , Jinna Shi , Qian Xia , Surendra P. Shah","doi":"10.1016/j.conbuildmat.2025.141987","DOIUrl":"10.1016/j.conbuildmat.2025.141987","url":null,"abstract":"<div><div>In previous studies, municipal solid waste incineration fly ash (MSWIFA) demonstrated low compressive strength when incorporated into cement-based materials, primarily due to the lack of active silicon. Thus, nano-based silica (NS) has been partially introduced to mitigate the performance degradation caused by MSWIFA; while it also led to additional challenges. Consequently, silica powder (SP) with larger particle sizes was considered as an alternative. The introduction of SP prepared from waste silica gel desiccants not only supplements MSWIFA with active silicon, but also reduces the cost and embodied carbon emissions. In this study, the enhancing effect of NS and SP were compared based on the evaluation of the MSWIFA-cement composites from the aspects of macro performance, microstructure, leaching of toxic heavy metals, and embodied carbon emissions. The results indicate that the introduction of SP significantly enhances the mechanical properties of the composite by supplementing active silicon and promoting the formation of C-S-H gels. The 5 wt% SP-modified composite demonstrated optimal performance, generating 6.5 % more C-S-H gel compared to the 1.0 wt% NS formulation. Its 28-d compressive strength reached 39.34 MPa, representing a 3.53 % enhancement. Notably, the composite reduces embodied carbon by 56 kg CO₂e/m³ and 38 kg CO₂e/m³ compared to the control group (named as CON) and the 1.0 wt% NS formulation, respectively. Moreover, it exhibits effective heavy metal stabilization/solidification performance, achieving immobilization efficiencies exceeding 95 % for Cr, Ni, Cu, Zn, and Cd ions, thereby complying with the regulatory limits specified in GB 5085.3–2007. This research provides a comprehensive solution for the effective utilization of MSWIFA and SP in cement-based materials.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"486 ","pages":"Article 141987"},"PeriodicalIF":7.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178616","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

Stabilization/solidification of composite heavy metal contaminated soil using a novel red mud-slag based geopolymer (RM-SGP): Performance and mechanisms 新型红泥-矿渣基地聚合物（RM-SGP）稳定/固化复合重金属污染土壤的性能与机理

IF 7.4 1区工程技术

Construction and Building Materials Pub Date : 2025-05-30 DOI: 10.1016/j.conbuildmat.2025.141996

Lu Zhou , Xin Xu , Qing Wang , Junboum Park , Yongming Han , Lisheng Guo , Yuchen Guo , Bing Song

{"title":"Stabilization/solidification of composite heavy metal contaminated soil using a novel red mud-slag based geopolymer (RM-SGP): Performance and mechanisms","authors":"Lu Zhou , Xin Xu , Qing Wang , Junboum Park , Yongming Han , Lisheng Guo , Yuchen Guo , Bing Song","doi":"10.1016/j.conbuildmat.2025.141996","DOIUrl":"10.1016/j.conbuildmat.2025.141996","url":null,"abstract":"<div><div>This study developed a novel geopolymer (RM-SGP) using industrial solid wastes red mud and slag activated by sodium silicate, aiming to remediate composite heavy metal contaminated soil. The effects of aluminosilicate component dosage, alkali equivalent, and heavy metal concentration on the unconfined compressive strength (UCS), toxicity leaching characteristics, resistivity, pH, and electrical conductivity (EC) of RM-SGP solidified composite heavy metal contaminated soil were systematically investigated. Additionally, the chemical composition and microstructural characteristics of solidified soil were analyzed using XRD, FTIR, SEM, and NMR tests to elucidate the solidification mechanisms. The results demonstrated that RM-SGP exhibited excellent solidification efficacy for composite heavy metal contaminated soil. Optimal performance occurred at 15 % aluminosilicate component dosage and 16 % alkali equivalent, achieving UCS > 350 kPa and compliant heavy metal leaching (excluding Cd in high-concentration groups). Acid/alkaline leaching tests revealed distinct metal behaviors: Cu/Cd decreased progressively, while Pb initially declined then rebounded. Microstructural analysis indicated that RM-SGP generated abundant hydration products (e.g., C-A-S-H, N-A-S-H gels), which acted as cementitious substances wrapping soil particles and filling and connecting pores, thereby increasing the soil’s compactness and improving the solidification effect. Furthermore, heavy metal ions were solidified through adsorption, encapsulation, precipitation, ion exchange, and covalent bond et al., transforming their active states into less bioavailable forms, proving novel insights into the remediation of composite heavy metal contaminated soils and the resource utilization of industrial solid wastes.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"486 ","pages":"Article 141996"},"PeriodicalIF":7.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178705","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

Study of macro-/micro-properties and in-situ mineralization mechanism of CO2 foam concrete based on solid waste-derived SAC-gypsum composite 固废源sac -石膏复合材料CO2泡沫混凝土宏微观性能及矿化机理研究

IF 7.4 1区工程技术

Construction and Building Materials Pub Date : 2025-05-30 DOI: 10.1016/j.conbuildmat.2025.141911

Chuanqi Wen , Jingwei Li , Qingke Meng , Shizhao Yang , Zhiliang Chen , Xujiang Wang , Yuzhong Li , Xinyu Wang , Xun Sun , Lichun Mu , Linxia Shi , Wenlong Wang

{"title":"Study of macro-/micro-properties and in-situ mineralization mechanism of CO2 foam concrete based on solid waste-derived SAC-gypsum composite","authors":"Chuanqi Wen , Jingwei Li , Qingke Meng , Shizhao Yang , Zhiliang Chen , Xujiang Wang , Yuzhong Li , Xinyu Wang , Xun Sun , Lichun Mu , Linxia Shi , Wenlong Wang","doi":"10.1016/j.conbuildmat.2025.141911","DOIUrl":"10.1016/j.conbuildmat.2025.141911","url":null,"abstract":"<div><div>CO<sub>2</sub> foam concrete (CFC) has a promising application in the field of building energy conservation and carbon reduction. The cement-based composite is critical to the mechanical performance, microstructure, and CO<sub>2</sub> sequestration of CFC. In this paper, a solid waste-derived sulphoaluminate cement (SAC)-gypsum composite with high strength and water resistance properties was explored using solid waste-based SAC, hemihydrate desulfurization gypsum and supplementary cementitious materials. Then, the SAC-gypsum composite and CO<sub>2</sub> foam were used to prepare CFC with high strength, steam-free curing and low thermal conductivity, and the influence of different CO<sub>2</sub> concentrations, CO<sub>2</sub> gas flow rates and CO<sub>2</sub> foam dosages on CFC preparation was investigated. The prepared CFC showed properties of high strength, steam-free curing and low thermal conductivity. The compressive strengths of CFC were 6.55–9.45 MPa (1.54–1.96 times of air foam concrete). Meanwhile, CFC achieved CO<sub>2</sub> sequestration of 2.05 wt% of the raw material, and the comprehensive carbon emissions was 90.90–115.27 kg CO<sub>2</sub>/ton. It was found that the in-situ CO<sub>2</sub> mineralization reaction in CFC had completed in early-age, and the mineralization products i.e., CaCO<sub>3</sub> and amorphous gel on the foam wall enhanced the early-age and later-age performance of CFC. This study provides a promising approach towards green, low-carbon and high-performance foam concrete, as well as sustainable construction.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"486 ","pages":"Article 141911"},"PeriodicalIF":7.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144166200","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 mechanical properties, shrinkage mitigation, and bond performance of recycled powder based alkali-activated paste for surface enhancement of recycled concrete aggregate 再生混凝土集料表面增强用粉基碱活化膏体的机械性能、收缩减缓性能和粘结性能

IF 7.4 1区工程技术

Construction and Building Materials Pub Date : 2025-05-30 DOI: 10.1016/j.conbuildmat.2025.141993

Feng Xie , Lei Bao , Yu Zheng , Liang Chen , Ruipan Wang , Gui Li , Jifei Cui

{"title":"The mechanical properties, shrinkage mitigation, and bond performance of recycled powder based alkali-activated paste for surface enhancement of recycled concrete aggregate","authors":"Feng Xie , Lei Bao , Yu Zheng , Liang Chen , Ruipan Wang , Gui Li , Jifei Cui","doi":"10.1016/j.conbuildmat.2025.141993","DOIUrl":"10.1016/j.conbuildmat.2025.141993","url":null,"abstract":"<div><div>This study explored a potential recycled powder-based alkali-activated slag/fly ash material (AASFRP) for the modification of recycled concrete aggregates (RCA). The workability, mechanical properties, drying shrinkage, and microstructure of the AASFRP paste, as well as the interfacial bonding performance of RCA, were investigated. To mitigate the high shrinkage inherent in alkali-activated materials, polypropylene glycol-based shrinkage-reducing admixtures (SRAs) were incorporated into the AASFRP. The results indicated that replacing up to 30 % of the recycled concrete powder (RP) enhanced workability, reduced drying shrinkage, and achieved compressive strengths exceeding 60 MPa. Micro-analytical assessments revealed that RP facilitated the formation of C-(A)-S-H gel, thereby increasing the proportion of harmless or less harmful pores. Specifically, at 30 % RP replacement, harmful and more harmful pores decreased by 36.8 % and 17.5 %, respectively. SRAs further promoted the formation of expansive hydrotalcite, reducing drying shrinkage by 32.1 % at a 3 % dosage. BSE imaging and microhardness testing demonstrated that 30 % RP in AASFRP refined the new interfacial transition zone (NITZ), confirming its efficacy in RCA surface treatment.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"486 ","pages":"Article 141993"},"PeriodicalIF":7.4,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144178620","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