Cement & concrete composites最新文献_第3页

An innovative strategy for CO2 conversion and utilization: Semi-wet carbonation pretreatment of wollastonite to prepare carbon-fixing products and produce LC3

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-19 DOI: 10.1016/j.cemconcomp.2025.106050

Yi-Sheng Wang , Li-Yi Meng , Lei Chen , Xiao-Yong Wang

{"title":"An innovative strategy for CO2 conversion and utilization: Semi-wet carbonation pretreatment of wollastonite to prepare carbon-fixing products and produce LC3","authors":"Yi-Sheng Wang , Li-Yi Meng , Lei Chen , Xiao-Yong Wang","doi":"10.1016/j.cemconcomp.2025.106050","DOIUrl":"10.1016/j.cemconcomp.2025.106050","url":null,"abstract":"<div><div>Limestone calcined clay cement (LC<sup>3</sup>) is considered the most promising alternative to Portland cement. This research proposes an innovative carbon conversion and utilization strategy that provides greater flexibility in the production of LC<sup>3</sup>. In this study, a carbon-fixing product with a CO<sub>2</sub> uptake of 29.39% was prepared via semi-wet carbonation pretreatment of wollastonite. This product can be used to replace limestone in LC<sup>3</sup> and play an effective synergistic role. This study was conducted to investigate the morphology and phase change of carbonated wollastonite (CWS) before and after preparation. The effects of CWS and natural wollastonite on the hydration kinetics, workability, mechanical properties, and durability were investigated through comprehensive experiments. Furthermore, the composition, porosity, and microstructural changes were characterized and analyzed. The results show that CWS has multiple properties, such as carbonate properties, synergistic effects, and pozzolanic reactions. Using CWS as a carbonate source in LC<sup>3</sup> increased the compressive strength and resistivity by 11.1 % and 36 %, respectively. The mortar exhibited increased carbonation durability because of the densification effect on the microstructure of the amorphous silica gel. The superposition of the synergistic effect and pozzolanic reaction reduced the total porosity of the hardened paste from 28.32 % to 21.43 %. The results of this study highlight the potential value of carbon-fixing products in the development of LC<sup>3</sup> composites and additional CO<sub>2</sub> utilization opportunities. This study also explored the future development prospects of this strategy, which is expected to provide new ideas and a practical basis for promoting the sustainable development of the construction industry.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106050"},"PeriodicalIF":10.8,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653548","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

Experimental and Mechanical-based Analysis of Fatigue-Induced Pull-Out Degradation in Single Hooked-End Steel Fiber in Fiber-Reinforced Cementitious Composites

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-18 DOI: 10.1016/j.cemconcomp.2025.106054

Mohamed Adel , Wang Li , Yan Xiao , Tamon Ueda

{"title":"Experimental and Mechanical-based Analysis of Fatigue-Induced Pull-Out Degradation in Single Hooked-End Steel Fiber in Fiber-Reinforced Cementitious Composites","authors":"Mohamed Adel , Wang Li , Yan Xiao , Tamon Ueda","doi":"10.1016/j.cemconcomp.2025.106054","DOIUrl":"10.1016/j.cemconcomp.2025.106054","url":null,"abstract":"<div><div>Fatigue analysis of steel fiber-reinforced cementitious composites (SFRCC) is crucial for structural design and safety assessment under repeated loading cycles. Experimental studies have demonstrated cyclic degradation in SFRCC, attributed to the deterioration of fiber-bridging strength. However, a comprehensive analytical quantification of fatigue-dependent parameters for deformed fibers across multiple scales remains limited. This study aims to characterize the fatigue dependency of SFRCC at the fiber-scale through analytical models based on experimental investigations. Static and fatigue pull-out tests were conducted on single hooked-end steel fibers embedded with a 20 mm length. Fibers were initially pulled to varying displacement levels (0.125, 0.25, 0.50, 0.75, 1.00, 2.50, 4.00, and 5.00 mm) before cyclic loading. Fatigue tests at a frequency of 5 Hz continued up to two million loading cycles or until pull-out failure, during which the fiber hook was progressively straightened. X-ray Computed Tomography (CT) scans were employed to investigate the associated failure mechanisms. A novel mechanical model was proposed to capture the displacement evolution rate during fatigue pull-out loading and predict the fatigue life. This model demonstrates a satisfactory correlation with the experimental results, providing a valuable tool for understanding and predicting the fatigue behavior of SFRCC.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106054"},"PeriodicalIF":10.8,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653549","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

Filament stitching: An architected printing strategy to mitigate anisotropy in 3D-Printed engineered cementitious composites (ECC)

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-18 DOI: 10.1016/j.cemconcomp.2025.106044

Wen Zhou, Yading Xu, Zhaozheng Meng, Jinbao Xie, Yubao Zhou, Erik Schlangen, Branko Šavija

{"title":"Filament stitching: An architected printing strategy to mitigate anisotropy in 3D-Printed engineered cementitious composites (ECC)","authors":"Wen Zhou, Yading Xu, Zhaozheng Meng, Jinbao Xie, Yubao Zhou, Erik Schlangen, Branko Šavija","doi":"10.1016/j.cemconcomp.2025.106044","DOIUrl":"10.1016/j.cemconcomp.2025.106044","url":null,"abstract":"<div><div>Anisotropy in 3D-printed concrete structures has persistently raised concerns regarding structural integrity and safety. In this study, an architected 3D printing strategy, “stitching”, was proposed to mitigate anisotropy in 3D-printed Engineered Cementitious Composites (ECC). This approach integrates the direction-dependent tensile resistance of extruded ECC, the mechanical interlocking between three-dimensional layers, and a deliberately engineered interwoven interface system. As a result, the out-of-plane direction of the printed structure can be self-reinforced without external reinforcements. Four-point bending tests demonstrated that the “stitching” pattern induced multi-cracking and flexural-hardening behavior in the out-of-plane direction, boosting its energy dissipation to 343 % of the reference “parallel” printing and achieving 48.6 % of cast ECC. Additionally, micro-CT scanning and acoustic emission tests further validated the controlled crack propagation enabled by the engineered interface architecture. The proposed strategy has been proven to substantially alleviate anisotropy and enhance structural integrity.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106044"},"PeriodicalIF":10.8,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642851","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

Early hydration and microstructure formation of ultra-rapid hardening alkali-activated slag cement (URHA) at presence of MgO

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-18 DOI: 10.1016/j.cemconcomp.2025.106057

Ziye Huang , Zuhua Zhang , Cheng Shi , Yingcan Zhu , Zhengning Zhou , Xiaolong Jia , Qiang Ren , Zhengwu Jiang

{"title":"Early hydration and microstructure formation of ultra-rapid hardening alkali-activated slag cement (URHA) at presence of MgO","authors":"Ziye Huang , Zuhua Zhang , Cheng Shi , Yingcan Zhu , Zhengning Zhou , Xiaolong Jia , Qiang Ren , Zhengwu Jiang","doi":"10.1016/j.cemconcomp.2025.106057","DOIUrl":"10.1016/j.cemconcomp.2025.106057","url":null,"abstract":"<div><div>The fundamentals of hydration process of an ultra-rapid hardening alkali-activated slag cement (URHA) was studied for understanding the link between mechanical properties and microstructure development. By employing combined application of Raman spectroscopy, thermogravimetry (TG), X-ray diffractometry (XRD) and hydrogen low field <sup>1</sup>H nuclear magnetic resonance (LF <sup>1</sup>H NMR), it revealed that the mixing MgO into the URHA led to the formation of magnesium silicate hydrates (M-S-H), followed by the rapid development of calcium-alumino-silicate hydrates (C-A-S-H) and hydrotalcite (Ht). This not only altered the composition of the hydration products but also increased the reaction extent of early slag reactions, resulting in the formation of a more compact microstructure. The presence of MgO was proven to reduce chemical shrinkage (by 57.6 % when 12 % MgO was used), and increased compressive strength at 1 h. The formation and spacial distribution of Mg-containing phases were found to have positive effect on sustaining strength development in the later stages of 1 day and 3 days. This study provides an insight of the hydration mechanism of MgO-modified URHA, which can help predict hydration kinetics and performance for real applications.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106057"},"PeriodicalIF":10.8,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653550","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

Repetitive water replenishment in CO2 curing: Enhancement in carbon uptake, reactivity, crystal development, and mechanical properties of low calcium binder composites 二氧化碳固化过程中的重复补水：提高低钙粘结剂复合材料的碳吸收、反应性、晶体发育和机械性能

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-17 DOI: 10.1016/j.cemconcomp.2025.106053

Seongmin Cho, Heongwon Suh, Jaeyeon Park, Seonghoon Jeong, Jin Park, Sungchul Bae

{"title":"Repetitive water replenishment in CO2 curing: Enhancement in carbon uptake, reactivity, crystal development, and mechanical properties of low calcium binder composites","authors":"Seongmin Cho, Heongwon Suh, Jaeyeon Park, Seonghoon Jeong, Jin Park, Sungchul Bae","doi":"10.1016/j.cemconcomp.2025.106053","DOIUrl":"10.1016/j.cemconcomp.2025.106053","url":null,"abstract":"<div><div>Water plays a crucial role in the carbonation and phase evolution of low-calcium binders (LCBs) under a CO<sub>2</sub> curing environment. This study aimed to improve the mechanical properties of LCB composites through repetitive water replenishment during curing and investigate their impact on microstructural phase evolution and strength development. To assess the effect of the amount of water replenished, distilled water containing 5, 10, and 15 wt% of cement paste was introduced into the samples at 1, 3, 6, and 12 h during CO<sub>2</sub> curing. Water replenishment significantly improved the reaction degree of the LCB, resulting in a characteristic microstructure due to the distinctive CaCO<sub>3</sub> growth. Notably, the samples with water replenishment exhibited a substantial increase in compressive strength, up to two times higher than those without water supplementation, after 24 h of curing. Therefore, the addition of water to LCB composites during CO<sub>2</sub> curing enhances the chemical reactions and refines the microstructure.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106053"},"PeriodicalIF":10.8,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143640567","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

Carbonation of natural fibers reinforced MgO-SiO2 (NFs-MS) composites

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-17 DOI: 10.1016/j.cemconcomp.2025.106052

Bo Wu, Jishen Qiu

{"title":"Carbonation of natural fibers reinforced MgO-SiO2 (NFs-MS) composites","authors":"Bo Wu, Jishen Qiu","doi":"10.1016/j.cemconcomp.2025.106052","DOIUrl":"10.1016/j.cemconcomp.2025.106052","url":null,"abstract":"<div><div>The heavy reliance of reactive magnesia cement (RMC) on CO<sub>2</sub> sources to gain sufficient mechanical strength limits its productivity. The present work developed natural fibers reinforced MgO-SiO<sub>2</sub> (NFs-MS) composites, in which the formation of magnesium-silicate-hydrate (M-S-H) yielded sufficient early strength (e.g., >30 MPa), and subsequent carbonation of residual brucite enabled continuous strength development (e.g., >70 MPa). The presence of NFs in MS composites not only accelerates the strength gain under moisture curing and subsequent carbonation curing, but also effectively improves the volume stability and CO<sub>2</sub> sequestration. Moreover, carbonation curing densified the fiber-matrix interface zone, leading to improved fiber-matrix interfacial properties and tensile performance. The results from aqueous carbonation test show that the synthetic M-S-H has greater chemical stability compared to MgO/brucite. However, partial leaching of Mg<sup>2+</sup> from M-S-H was also observed, implying the carbonation potential of M-S-H phase. These findings suggest that NFs-MS composites hold great potential to be directly applied in load-bearing structures without requirement for special CO<sub>2</sub> pre-curing.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106052"},"PeriodicalIF":10.8,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143640566","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

Investigation of mechanical properties and damage characterization of cement pastes prepared by coupled carbonation-hydration curing 碳化-水化耦合固化法制备的水泥浆的力学性能和损伤特征研究

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-17 DOI: 10.1016/j.cemconcomp.2025.106049

Qinglong Qin , Boyang Su , Zihan Ma , Rui Sun , Peiliang Shen , Jiangshan Li , Chi Sun Poon

{"title":"Investigation of mechanical properties and damage characterization of cement pastes prepared by coupled carbonation-hydration curing","authors":"Qinglong Qin , Boyang Su , Zihan Ma , Rui Sun , Peiliang Shen , Jiangshan Li , Chi Sun Poon","doi":"10.1016/j.cemconcomp.2025.106049","DOIUrl":"10.1016/j.cemconcomp.2025.106049","url":null,"abstract":"<div><div>To achieve carbon reduction, a coupled carbonation-hydration curing approach has been developed. This study employs the acoustic emission (AE) technique to analyze the mechanical properties and damage characterization of cement paste under this curing method. Microscopic techniques clarify the evolution of products, microstructures and micromechanical parameters, highlighting their impact on mechanical behavior. Results indicate that the carbonation-hydration equilibrium is achieved when the ratio of CaCO<sub>3</sub> to amorphous content is less than 2. In this system, C-S-H gels are predominantly formed, while the CaCO<sub>3</sub> content remains minimal. At the balance system, the compressive strength increases by 4.16 %–16.25 %, while the pore volume in the range of 1–200 nm decreases by 13.19 %–19.54 % compared to standard curing. Conversely, the ratio greater than 2 results in over-carbonation, with CaCO<sub>3</sub> as the dominant product and few C-S-H gels. In the over-carbonation system, the compressive strength and pore volume in the range of 1–200 nm decrease by 13.21 %–34.62 % and 21.55 %–40.85 %, respectively, compared to standard curing. Under coupled carbonation-hydration curing, cement pastes exhibit significant stress instability, with damage primarily from tensile cracks in the balanced systems and mixed shear-tensile or tensile cracks in the over-carbonated systems.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106049"},"PeriodicalIF":10.8,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143640572","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 role of water during the middle or later periods of Class F fly ash-based geopolymerization 水在 F 级粉煤灰基土工聚合中后期的作用

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-15 DOI: 10.1016/j.cemconcomp.2025.106045

Xiaonan Ge , Yiming Zhang , Xiang Hu , Minjie Wen , Caijun Shi

{"title":"The role of water during the middle or later periods of Class F fly ash-based geopolymerization","authors":"Xiaonan Ge , Yiming Zhang , Xiang Hu , Minjie Wen , Caijun Shi","doi":"10.1016/j.cemconcomp.2025.106045","DOIUrl":"10.1016/j.cemconcomp.2025.106045","url":null,"abstract":"<div><div>The free water in the interconnected pores plays a significant role in supporting the development of fly ash-based geopolymerization reactions during the middle and later periods of the process. In this paper, the free water loss and mechanical properties of geopolymers within the different curing methods were tested. Through the analysis of X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), energy disperse spectroscopy (EDS), and low-field nuclear magnetic resonance (NMR) results, the differential tendencies of micro-characteristics were observed. In the period of 28–56 days, the main reactive modes probably evolved into the continuous generation of oligomers that increase the amorphous phase content (APC) and the polycondensation between formed geopolymer binders and oligomers that promotes the optimization of Si/Al molar ratio and porosity. The varied free water content led to the change in the alkalinity of the pore solution that acted on the geopolymerizaiton, and the physical actions of water, including softening, lubrication, and drying shrinkage, also affected the mechanical performance of specimens. The research found that the remaining water content composed of the trapped and free water showed a threshold of at least 6.40 %, lower than which the geopolymerization would be suspended. In general, the phenomenon of differentiation and regression of mechanics indicates that the variation of water content with limits can only impact the geopolymerization in a relatively short period.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106045"},"PeriodicalIF":10.8,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143631262","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

Synthesis of geopolymer composites utilizing PVA-modified basalt fibers and foundry waste: Fundamental properties, cracking resistance and fracture toughness

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-15 DOI: 10.1016/j.cemconcomp.2025.106046

Yuwei Zhang, Chengliang Zhou, Yafeng Gong, Fei Wu, Yuheng Liu, Jiaxiang Song, Fuyu Wang

{"title":"Synthesis of geopolymer composites utilizing PVA-modified basalt fibers and foundry waste: Fundamental properties, cracking resistance and fracture toughness","authors":"Yuwei Zhang, Chengliang Zhou, Yafeng Gong, Fei Wu, Yuheng Liu, Jiaxiang Song, Fuyu Wang","doi":"10.1016/j.cemconcomp.2025.106046","DOIUrl":"10.1016/j.cemconcomp.2025.106046","url":null,"abstract":"<div><div>Coal gangue/slag-based geopolymer composites (CSGC) have garnered significant attention in sustainable construction due to their low-carbon footprint, but their high brittleness remains a critical limitation. This study addresses this challenge by modifying basalt fiber (BF) with polyvinyl alcohol (PVA) to enhance CSGC. A novel porosity detection program, with an average accuracy exceeding 98 % for pores larger than 10 pixels (0.4 mm), was developed to analyze pore evolution. Combined with a multi-scale testing approach, the study evaluates shrinkage, fracture toughness, compressive strength, and flexural strength of fiber-reinforced CSGC. Results revealed that PVA coating enhanced fiber-CSGC matrix bonding via chemical crosslinking, such as O-Al-O bonds, and mechanical interlocking, achieving 15.9 % and 19.1 % improvements in the 28-d flexural and compressive strength of modified basalt fibers (MBF)-reinforced CSGC, respectively. Acoustic emission (AE) analysis indicated that fibers shifted the dominant cracking mode from shear to a mixed tensile-shear mode (20.99 % tensile cracks), thereby enhancing CSGC toughness. Moreover, double-K fracture model analysis, based on digital image correlation (DIC) test results, confirmed that MBF outperforms unmodified fibers in toughening effects, with increases of 50.0 % and 32.4 % in initiation and unstable fracture toughness, respectively. This study presents an effective strategy for reducing brittleness in geopolymers through interface-engineered fiber reinforcement, which is expected to promote the development of high-performance, sustainable construction materials.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106046"},"PeriodicalIF":10.8,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143627651","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

Influence of surface carbonation on the electrochemical chloride extraction of recycled aggregate concrete and sensitivity analysis 表面碳化对再生骨料混凝土电化学提取氯化物的影响及敏感性分析

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-15 DOI: 10.1016/j.cemconcomp.2025.106041

Feng Qu , Yuhao He , Congtao Sun , Lin Chen , Gang Peng , Gongxun Wang , Hailong Hou

{"title":"Influence of surface carbonation on the electrochemical chloride extraction of recycled aggregate concrete and sensitivity analysis","authors":"Feng Qu , Yuhao He , Congtao Sun , Lin Chen , Gang Peng , Gongxun Wang , Hailong Hou","doi":"10.1016/j.cemconcomp.2025.106041","DOIUrl":"10.1016/j.cemconcomp.2025.106041","url":null,"abstract":"<div><div>At present, applying ECE technology to existing concrete structures to enhance durability and service life is feasible. However, the combined effects of chloride salts and carbonation in marine environments introduce complex influence mechanisms on concrete structures treated with ECE, especially for reinforced concrete projects incorporating RCA. This paper studies the effect of different factors on the ECE of carbonated RAC. The effects include RCA quality and replacement rate, FA admixture, electrochemical parameters, etc. The results indicate that optimal dechlorination efficiency is observed at FA content of 10 %. Overall, increased replacement of RCA improves the dechlorination efficiency with a 26.19 % increase recorded at 100 % replacement ratio compared to NAC. After carbonation, the decomposition of hydration products such as C-S-H reduced the mechanical properties of concrete, but the extended carbonation duration enhanced the ECE effectiveness. With the extension of carbonation time to 28d, the dechlorination efficiency increases by 14.27 %. Longer times and higher energizing currents can enhance for ECE. Dechlorination efficiency of carbonated RAC increased by 42.8 % after 28d of chloride extraction, compared to 7d.Sensitivity analysis highlighted that the electrochemical parameters had the most significant effect on ECE effectiveness. The sensitivity of current density to dechlorination efficiency and the sensitivity of chloride extraction time to the [Cl<sup>−</sup>]/[OH<sup>−</sup>] are 0.241 and 5.418, respectively. This will contribute to improving the durability of RAC structures in marine environments and advancing low-carbon engineering.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106041"},"PeriodicalIF":10.8,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143631263","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