Cement & concrete composites最新文献_第4页

Reaction kinetics of Na2CO3-activated blast furnace slag with organic ligands: Insights from electrical conductivity measurements

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-11 DOI: 10.1016/j.cemconcomp.2025.106021

Julson Aymard Tchio , Elijah Adesanya , Rafal Sliz , Brant Walkley , Juho Yliniemi

{"title":"Reaction kinetics of Na2CO3-activated blast furnace slag with organic ligands: Insights from electrical conductivity measurements","authors":"Julson Aymard Tchio , Elijah Adesanya , Rafal Sliz , Brant Walkley , Juho Yliniemi","doi":"10.1016/j.cemconcomp.2025.106021","DOIUrl":"10.1016/j.cemconcomp.2025.106021","url":null,"abstract":"<div><div>Electrical conductivity measurement using impedance spectroscopy could be a valuable technique for monitoring the various reaction processes of cementitious materials and predicting their long-term durability. In this study, alternating current impedance spectroscopy was employed to investigate the influence of two ligands, 2,3-dihydroxynaphthalene and 3,4-dihydroxybenzoic acid with a 0.1 wt% dosage, on the hardening process of four types of blast furnace slag (BFS) activated with sodium carbonate solution. The objectives of the study were to investigate whether impedance spectroscopy could be used for estimating the reactivity of BFS and monitoring the reaction kinetics of this type of binder as well as evaluating the correlation between electrical conductivity and reaction heat, pore solution chemistry, setting time, flowability and compressive strength. The results demonstrated that both ligands accelerated the hardening process and increased compressive strength, which was confirmed by the various techniques used. The measured electrical conductivities varied among BFS pastes due to differences in their pore solution composition and microstructure and correlated with compressive strength evolution. The results demonstrated that impedance spectroscopy is sensitive enough to detect differences in conductivity due to differences in the reactivity of BFS and the effect of low a dosage of ligands in the binder. However, because of the overall complexity of reactions in this type of binder, responses in electrical conductivity do not show systematic trends.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106021"},"PeriodicalIF":10.8,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143590060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation on the Cl− and heavy metals stabilization of MSWI fly ash by incorporating Portland cement and carbonation

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-11 DOI: 10.1016/j.cemconcomp.2025.106043

Dezhi Zhao , Hexiang Wang , Caihong Xue , Qingxin Zhao , Wenyue Qi , Yuyang Tian

{"title":"Investigation on the Cl− and heavy metals stabilization of MSWI fly ash by incorporating Portland cement and carbonation","authors":"Dezhi Zhao , Hexiang Wang , Caihong Xue , Qingxin Zhao , Wenyue Qi , Yuyang Tian","doi":"10.1016/j.cemconcomp.2025.106043","DOIUrl":"10.1016/j.cemconcomp.2025.106043","url":null,"abstract":"<div><div>To achieve CO<sub>2</sub> and municipal solid waste incineration fly ash (MSWI-FA) utilization in construction and building materials production, in this study a novel carbon mixing method was proposed to prepare cement-MSWI-FA pastes with improved properties. The effect of carbon mixing and curing on the compressive strength, Cl<sup>−</sup> as well as heavy metal solidification and pore structure was investigated. The reaction products were analyzed with XRD, SEM-EDS and TG to reveal the role of CO<sub>2</sub> mixing on the phase assemblage development. The results showed that a ‘1.5 min normal mixing followed by 1.5 min carbon mixing’ procedure allowed the cement paste with 60 % MSWI-FA to obtain a compressive strength reaching 20 MPa at 28d. Compared with carbon curing, carbon mixing allowed easier and homogenous CO<sub>2</sub> diffusion, and thus increased the CO<sub>3</sub><sup>2−</sup>/HCO<sub>3</sub><sup>−</sup> in the pore solution for the formation of CaCO<sub>3</sub> and Mc. The CaCO<sub>3</sub> functioned as filler to refine the pore structure and thus contributed to the compressive strength improvement, while the Mc was converted to the Fs and AFt with the presence of Cl<sup>−</sup> and SO<sub>4</sub><sup>2−</sup> at 28d, enhancing the Cl<sup>−</sup> and heavy metals solidification. The proposed method and the test results of this study can provide technique support for the utilization of CO<sub>2</sub> and MSWI-FA.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106043"},"PeriodicalIF":10.8,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143599059","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

On the subtilities of rebar corrosion behaviour in cracked concrete

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-11 DOI: 10.1016/j.cemconcomp.2025.106038

Gang Li , Moh Boulfiza , Richard Evitts

{"title":"On the subtilities of rebar corrosion behaviour in cracked concrete","authors":"Gang Li , Moh Boulfiza , Richard Evitts","doi":"10.1016/j.cemconcomp.2025.106038","DOIUrl":"10.1016/j.cemconcomp.2025.106038","url":null,"abstract":"<div><div>This study presents a comprehensive mechanistic corrosion model to simulate rebar corrosion in non-uniform corrosive microenvironments caused by cracking and exposure conditions. The proposed model comprehensively investigates all possible corrosion mechanisms in cracked concrete, addressing an experimental phenomenon that has perplexed experts for decades. In particular, it aims to elucidate the marked difference in corrosion behaviour observed in the presence of thin versus wide cracks. This study demonstrates that self-healing is the sole mechanism differentiating the corrosion behavior of thin and wide cracks, a finding enabled by advanced numerical modeling and experimental validation. Achieving this required a sophisticated physics-based model capable of capturing the major features of reinforcement corrosion in cracked concrete. The ability to selectively activate or deactivate specific mechanisms in the model provides a unique lens to isolate their contributions, which is often impractical in experimental setups. The findings of this study provide valuable insights into the concept of a “critical crack width”, below which reinforcement corrosion is unlikely to pose a significant concern.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106038"},"PeriodicalIF":10.8,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143590057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of hematite in red mud on hydration characteristics and environmental performance of cementitious materials 赤泥中的赤铁矿对水泥基材料水化特性和环境性能的影响

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-08 DOI: 10.1016/j.cemconcomp.2025.106035

Pengfei Wu , Chao Wei , Xiaoming Liu , Zengqi Zhang , Yang Xue , Xinyue Liu

{"title":"Impact of hematite in red mud on hydration characteristics and environmental performance of cementitious materials","authors":"Pengfei Wu , Chao Wei , Xiaoming Liu , Zengqi Zhang , Yang Xue , Xinyue Liu","doi":"10.1016/j.cemconcomp.2025.106035","DOIUrl":"10.1016/j.cemconcomp.2025.106035","url":null,"abstract":"<div><div>Red mud (RM), a waste by-product of alumina production, is increasingly used in cementitious materials. However, the high iron content and alkaline substances in RM, in addition to heavy metal elements, hinder its utilisation in cementitious materials. To overcome these issues, a ternary system of RM, blast furnace slag (BFS), and cement was prepared to assess the effects of iron in RM on hydration and environmental performance. The results indicated that 97 % of the iron in RM exists in the form of Hematite. As the Hematite content in the system increases, the cumulative hydration heat, heavy metal immobilisation rate, hydration-product content, degree of polymerisation, initial and final setting times, as well as early compressive strength gradually decrease. However, the later strength of the matrix initially increases and then decreases. In addition, the soluble alkali in RM was utilised. When the Hematite content in the system is between 2.47 % and 7.82 % (corresponding to 9.68 %–31.28 % Hematite in RM), the mechanical properties of the matrix meet PO.42.5 standards, and the concentrations of hazardous elements such as Na in the leachate comply with China's drinking water standards (GB/T 5749-2022).</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106035"},"PeriodicalIF":10.8,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576158","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 characterization and constitutive modelling of the anisotropic dynamic compressive behavior of 3D printed engineered cementitious composites

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-08 DOI: 10.1016/j.cemconcomp.2025.105995

Meng Chen , Jianhua Cheng , Tong Zhang , Yuting Wang

{"title":"Experimental characterization and constitutive modelling of the anisotropic dynamic compressive behavior of 3D printed engineered cementitious composites","authors":"Meng Chen , Jianhua Cheng , Tong Zhang , Yuting Wang","doi":"10.1016/j.cemconcomp.2025.105995","DOIUrl":"10.1016/j.cemconcomp.2025.105995","url":null,"abstract":"<div><div>Engineered cementitious composites (ECC) offer a potential solution to the weak tensile strength and cracking issues of 3D printed concrete (3DPC), while their great performance under dynamic loading helps to broaden the application scope of 3D printing technology. This study systematically investigates the relationship between the dynamic compressive properties and the anisotropic behavior of 3DP-ECC under various strain rates through ultrasonic pulse velocity, quasi-static and dynamic compression, as well as novel sieving tests. The results indicate that the dynamic compressive behavior of 3DP-ECC shows a pronounced strain rate dependency especially in the Z-direction, while the mechanical anisotropy coefficient of the 3DP specimens decreased by 14.2% as the strain rate rose from 60 s<sup>−1</sup> to 120 s<sup>−1</sup>. In what follows, the fractal theory is applied to characterize the internal damage of 3DP-ECC in different orientations, indicating that the dynamic compressive strength and dissipation energy exhibit a linear relationship with the fractal dimension. Based on the modified viscoelastic theory and spatial transformation tensor method, the anisotropic damage dynamic compression constitutive model is developed to predict the stress-strain behavior of 3DP-ECC at different strain rates. The exploration of dynamic compression behavior and anisotropic constitutive relationships of 3DP-ECC provides a basis for further integrated practical applications under extreme strain rate conditions.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 105995"},"PeriodicalIF":10.8,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143576160","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

Thermodynamic effects of chloride's type and dosage on phase composition of magnesium oxysulfate cement and its impact on macro-properties

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-07 DOI: 10.1016/j.cemconcomp.2025.106032

Tong Li , Yuhao Zheng , Huisu Chen , Tingting Zhang , Rongling Zhang

{"title":"Thermodynamic effects of chloride's type and dosage on phase composition of magnesium oxysulfate cement and its impact on macro-properties","authors":"Tong Li , Yuhao Zheng , Huisu Chen , Tingting Zhang , Rongling Zhang","doi":"10.1016/j.cemconcomp.2025.106032","DOIUrl":"10.1016/j.cemconcomp.2025.106032","url":null,"abstract":"<div><div>As magnesium oxysulfate cement (MOS) finds more applications in salt lakes and marine environments, the interaction between Cl<sup>−</sup> and MOS has gained more attention. Nevertheless, a scarcity of previous studies has investigated the effects of chloride type and dosage on the phase composition of hardened MOS paste. This study creates a newly extended and internally consistent thermodynamic database to systematically explore the impacts of four chloride salts (NaCl, KCl, MgCl<sub>2</sub>, and CaCl<sub>2</sub>) on the phase assemblage of MOS at various chloride dosages, including chloride impurities (0–0.125 g/(100g MOS)), chloride attack (0–0.25 mol/(100g MOS)), and high-volume MgCl<sub>2</sub> (>0.05 mol/(100g MOS)). The predicted phase assemblages via thermodynamic modeling are validated using the experimental phase assemblages characterized by XRD from both the literature and our experiments. The gel-space ratio is used to bridge the relationship between phase composition and the compressive strength of samples. The feasibility of this correlation is confirmed by compressive strength from both the literature and our experiments.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106032"},"PeriodicalIF":10.8,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143569514","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 gypsum on reaction kinetics and microstructure of alkali-activated CaO‐FeOx‐SiO2 slag

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-07 DOI: 10.1016/j.cemconcomp.2025.106033

Vitalii Ponomar , Sima Kamali , Tero Luukkonen , Ailar Hajimohammadi , Katja Kilpimaa

{"title":"The effect of gypsum on reaction kinetics and microstructure of alkali-activated CaO‐FeOx‐SiO2 slag","authors":"Vitalii Ponomar , Sima Kamali , Tero Luukkonen , Ailar Hajimohammadi , Katja Kilpimaa","doi":"10.1016/j.cemconcomp.2025.106033","DOIUrl":"10.1016/j.cemconcomp.2025.106033","url":null,"abstract":"<div><div>Gypsum is commonly used in conventional cement systems to regulate setting time and enhance early strength. However, its role in alkali-activated materials (AAMs) is less well understood due to the distinct chemistry of precursors and reaction products. This study investigates the impact of synthetic and industrial gypsum on the reaction kinetics and microstructure of CaO-FeO<sub>X</sub>-SiO<sub>2</sub> slag activated with sodium silicate and sodium hydroxide, supported by dissolution-precipitation tests. Results demonstrate that gypsum addition to sodium silicate solution promotes the precipitation of C-S-H gel, which evolves into two distinct compositional varieties in the paste environment with slag, influencing the reaction kinetics. The early formation of Ca-rich gel accelerates the setting time but initially reduces the strength. The delayed formation of main Si-rich gel matrix leads to strength gain over time, with the 1 % industrial gypsum sample achieving 90 MPa at 28 days. In NaOH solutions, gypsum induces portlandite precipitation but the formation of a rod-like thaumasite phase (CaSiO<sub>3</sub>·CaCO<sub>3</sub>·CaSO<sub>4</sub>·15H<sub>2</sub>O) in the slag paste environment. The early formation of sulphate phases improves early mechanical performance but compromises durability due to the expansive nature of thaumasite growth. These findings underscore the dual role of gypsum in controlling setting time and strength in AAMs and highlight the need to optimize gypsum type and content to address challenges posed by precursor chemistry.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106033"},"PeriodicalIF":10.8,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143569516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Coupled mesoscale analysis of concrete shrinkage

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-06 DOI: 10.1016/j.cemconcomp.2025.106007

Yilin Wang , Giovanni Di Luzio , Jan Vorel , Jan Belis , Xinyan Guo , Roman Wan-Wendner

{"title":"Coupled mesoscale analysis of concrete shrinkage","authors":"Yilin Wang , Giovanni Di Luzio , Jan Vorel , Jan Belis , Xinyan Guo , Roman Wan-Wendner","doi":"10.1016/j.cemconcomp.2025.106007","DOIUrl":"10.1016/j.cemconcomp.2025.106007","url":null,"abstract":"<div><div>Cracking, driven by shrinkage and thermal strains, strongly influences the serviceability and durability of concrete structures. After several decades of use, cracking can cause structural deterioration and damage. Concrete shrinkage is sensitive to temperature and humidity variations in a complex hygrothermal environment. Therefore, an efficient numerical framework is essential to predict the structural response for all potential geometries and environmental conditions. This work presents a new multi-physics simulation framework coupling the mechanical behavior with chemical/physical processes of concrete while considering the meso-structure of concrete. The Lattice Discrete Particle Model (LDPM) is used the describe the mechanical response. The Hygro-Thermo-Chemical (HTC) model, which describes the moisture transport, heat transfer, and curing reaction, is solved using a flow lattice element (FLE) system dual to the mechanical mesh. The development of mechanical characteristics, as well as thermal and hygral eigenstrains owing to continued curing, is driven by the HTC model. In addition, a newly proposed 2-phase formulation for concrete shrinkage is introduced, considering the effect of aggregate volume and stiffness on concrete shrinkage. The results give robust predictions of macroscopic shrinkage for concretes with different mix proportions and indicate a better representation of meso-structural features than the previously proposed 1-phase formulation. To ensure the reliability of the results, five experimental campaigns from the literature were selected to calibrate and validate the numerical model. The model agrees well with the experimental data and offers new insights into local strain distribution and cracking behavior in heterogeneous materials at an acceptable computational cost.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106007"},"PeriodicalIF":10.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143560825","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

Recognition of the free slump in dry concrete mix: A 3D-digital image correlation test and the spatiotemporal variability

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-06 DOI: 10.1016/j.cemconcomp.2025.106012

Yangyi Zhang, Xueshi Liu, Jianyun Wang, Yun Gao

{"title":"Recognition of the free slump in dry concrete mix: A 3D-digital image correlation test and the spatiotemporal variability","authors":"Yangyi Zhang, Xueshi Liu, Jianyun Wang, Yun Gao","doi":"10.1016/j.cemconcomp.2025.106012","DOIUrl":"10.1016/j.cemconcomp.2025.106012","url":null,"abstract":"<div><div>Dry concrete mix has advantages of high construction efficiency and rapid early strength development. It has been employed extensively in a variety of sectors, including construction and pavement engineering. Traditional methods assessing its workability such as the Vebe test are susceptible to human error, which usually leads to the lack of the satisfactory accuracy in practice. To address the limitations of traditional methods, this study develops a three-dimensional digital image correlation (3D-DIC) method to meticulously recognize the free slump in dry concrete mix. Owing to the prominent advances in high precision and full-field measurement, the 3D-DIC method enables a novel monitoring and visualization of the free slump in terms of the spatiotemporal variability, i.e., the temporal evolution and the spatial variability. It is meanwhile possible to elucidate the spatiotemporal variability through two statistical models such as the Gaussian model and the semi variogram exponential model. Consequently, the 3D-DIC method presents two synergistic parameters of high accuracy other than a single one of low accuracy as used in traditional methods to quantify the free slump in dry concrete mix, which correspond respectively to the consistency and cohesiveness of the workability.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106012"},"PeriodicalIF":10.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143560824","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

Comparison of thermal and mechanochemical activation for enhancing pozzolanic reactivity of illite-rich shale

IF 10.8 1区工程技术

Cement & concrete composites Pub Date : 2025-03-06 DOI: 10.1016/j.cemconcomp.2025.106034

Pengfei Zhao , Alexander Ozersky , Alexander Khomyakov , Karl Peterson

{"title":"Comparison of thermal and mechanochemical activation for enhancing pozzolanic reactivity of illite-rich shale","authors":"Pengfei Zhao , Alexander Ozersky , Alexander Khomyakov , Karl Peterson","doi":"10.1016/j.cemconcomp.2025.106034","DOIUrl":"10.1016/j.cemconcomp.2025.106034","url":null,"abstract":"<div><div>To address the challenges associated with urban construction waste disposal and promote sustainable construction practices, this study investigates the feasibility of repurposing an illite-rich waste shale as a supplementary cementitious material (SCM) through thermal and mechanochemical activation. The aim of this study is to develop a deeper understanding of the relationship between the chemical reactivity of activated shales and the performance of blended cement mortars. Various properties, including phase transitions, particle size distribution, surface morphology, chemical reactivity, as well as mortar fresh properties and compressive strength, were analyzed for the activated shales. The results show that the mechanochemically activated shale exhibited a noticeable increase in pozzolanic reactivity compared to the calcined shale. The mechanochemically activated shale also displayed a more granular surface morphology, which is beneficial for early-age reactivity. A bimodal particle size distribution was observed in the mechanochemically activated shale, likely attributed to the agglomeration of amorphized fine particles. Furthermore, the mechanochemically activated shale had a less negative impact on workability, primarily due to the re-adsorbed surface moisture, which offset the increased water demand in the blended cements. At 20 %, 30 %, and 40 % cement substitution levels, the mechanochemically activated shale mortar mixtures developed compressive strengths comparable to those of the control mixture at both 7 and 28 days. More importantly, the practical significance of this study lies in the successful activation of the illite-rich shale using an attrition mill for the first time, an industrially-scalable milling technology.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"160 ","pages":"Article 106034"},"PeriodicalIF":10.8,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143560827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0