Cement and Concrete Research最新文献_第2页

Exploring the hydration potential and kinetics of Na-Ye'elimite and Ti-Ferrite solid solutions 探讨Na-Ye' limit和Ti-Ferrite固溶体的水化势和动力学

IF 13.1 1区工程技术

Cement and Concrete Research Pub Date : 2025-09-30 DOI: 10.1016/j.cemconres.2025.108046

Rahul Roy , Tobias Hertel , Christiane Rößler , Yiannis Pontikes

{"title":"Exploring the hydration potential and kinetics of Na-Ye'elimite and Ti-Ferrite solid solutions","authors":"Rahul Roy , Tobias Hertel , Christiane Rößler , Yiannis Pontikes","doi":"10.1016/j.cemconres.2025.108046","DOIUrl":"10.1016/j.cemconres.2025.108046","url":null,"abstract":"<div><div>The addition of Bauxite residue in the raw mix introduces Na<sup>+</sup> and Ti<sup>4+</sup> into the crystalline phases of calcium-sulfoaluminate (CSA) clinkers. To mimic such a system, Na-Fe-ye'elimite (C₃.₉N₀.₁A₂.₈F₀.₂Ŝ) and Ti-ferrite (C₂F₀.₇₆A₀.₂₄T₀.₁) were synthesized at 1285 °C, 2 h, and 1320 °C, 3 h, respectively. Quantitative X-ray diffraction (QXRD) revealed solid solutions with minor Ca-aluminates phases, whereas electron backscattered diffraction-energy dispersive spectroscopy (EBSD-EDS) could distinguish Na-rich orthorhombic and Fe-rich cubic ye'elimite polymorphs. Isothermal calorimetry showed the Na-Fe-ye'elimite phase drives early heat evolution, whereas higher ferrite and gypsum (M > 0) prolong induction and attenuate the main hydration peak. In ferrite-free mixes, the cubic-ye'elimite polymorph dissolves fastest, but when ferrite exceeds 33 wt%, its Fe<sup>3+</sup> release accelerates orthorhombic-ye'elimite dissolution, as confirmed by pore-solution analysis. After 28d, Na-Fe-ye'elimite is fully consumed at M (sulfate to ye'elimite molar ratio) ≥ 2 for ye'elimite-ferrite mixes, while ferrite remains partly inert, possibly from Ca<sup>2+</sup>/SO₄<sup>2−</sup> adsorb onto its Fe<img>Al surface. Limiting ferrite to ≤33 wt% is recommended to achieve more densification of the microstructure for better performance.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"199 ","pages":"Article 108046"},"PeriodicalIF":13.1,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145194949","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

Coupling EDS hypermaps and X-ray microtomography for advanced 3D microstructure characterization of cement paste: A step forward in multiscale modeling 耦合EDS超地图和x射线微断层扫描先进的水泥膏体三维微观结构表征：在多尺度建模向前迈进一步

IF 13.1 1区工程技术

Cement and Concrete Research Pub Date : 2025-09-30 DOI: 10.1016/j.cemconres.2025.108047

Mohammed Krameche , William Wilson , Arezki Tagnit-Hamou

{"title":"Coupling EDS hypermaps and X-ray microtomography for advanced 3D microstructure characterization of cement paste: A step forward in multiscale modeling","authors":"Mohammed Krameche , William Wilson , Arezki Tagnit-Hamou","doi":"10.1016/j.cemconres.2025.108047","DOIUrl":"10.1016/j.cemconres.2025.108047","url":null,"abstract":"<div><div>Investigating the microstructure of ordinary Portland cement (OPC) paste using X-ray micro-computed tomography (μ-CT) requires optimized acquisition and precise image segmentation to reliably differentiate phases. μ-CT image segmentation is challenged by the heterogeneous microstructure and limited contrast between microstructure phases in the X-ray linear attenuation coefficient. Conventional gray scale value thresholding often misclassifies phases, while previous machine learning (ML) approaches have relied on manually labeled training leading to subjectivity and replicability issues. This study proposes an innovative μ-CT image segmentation method for OPC paste, leveraging chemical information from quantitative energy dispersive spectroscopy (QEDS) mapping. The method workflow involves five steps: (1) μ-CT imaging to capture the 3D microstructure, (2) scanning electron microscopy backscattered electron (SEM-BSE) imaging and QEDS mapping to generate 2D phase maps, (3) image registration to align QEDS phase maps with μ-CT images, (4) phase separability optimization using denoising and sharpening of the μ-CT images, and (5) ML-based segmentation using the random forest approach and training labels from QEDS-derived phase maps. The proposed method effectively differentiates portlandite from hydrates matrix, as well as ferrite from clinker phases. This paper further details two main applications of the method: (1) quantification of phase assemblage, hydration degree, and particle size distribution (PSD) of residual anhydrous phases, with results compared to thermodynamic modeling, and (2) the first-ever comprehensive quantitative microstructural characterization of a grid of 32 microcube samples, revealing spatial heterogeneity in phase fractions, porosity, particle counts, and microcube volumes. These results provide critical input for calibrating and validating micromechanical upscaling models.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"199 ","pages":"Article 108047"},"PeriodicalIF":13.1,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145188960","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

An ASR exposure site after 30 years – Chemical composition of hydrates and ASR products 30年后的ASR暴露点-水合物和ASR产品的化学成分

IF 13.1 1区工程技术

Cement and Concrete Research Pub Date : 2025-09-30 DOI: 10.1016/j.cemconres.2025.108043

Maxime Ranger , Andreas Leemann , Benoit Fournier

引用次数: 0

How does aluminum sulfate-based alkali-free accelerator affect calcium silicate hydrate (C-S-H) formation in accelerated cement pastes? 硫酸铝基无碱促进剂如何影响水泥浆中水化硅酸钙（C-S-H）的形成？

IF 13.1 1区工程技术

Cement and Concrete Research Pub Date : 2025-09-29 DOI: 10.1016/j.cemconres.2025.108052

Xin Liu , Dining Li , Hui Xie , Jiachen Yao , Xuyan Shen , Haochuan Wang , Zhengyao Qu , Zuhua Zhang , Pan Feng

{"title":"How does aluminum sulfate-based alkali-free accelerator affect calcium silicate hydrate (C-S-H) formation in accelerated cement pastes?","authors":"Xin Liu , Dining Li , Hui Xie , Jiachen Yao , Xuyan Shen , Haochuan Wang , Zhengyao Qu , Zuhua Zhang , Pan Feng","doi":"10.1016/j.cemconres.2025.108052","DOIUrl":"10.1016/j.cemconres.2025.108052","url":null,"abstract":"<div><div>Alkali-free aluminum sulfate (AS)-based accelerators have become a widely adopted and indispensable admixture for shotcrete applications. However, their effects on the formation kinetics and properties of calcium silicate hydrate (C-S-H) – the primary hydrate in shotcrete – remain insufficiently understood. To bridge this knowledge gap, a combination of isothermal calorimetry, QXRD, and TGA was employed to uncover the temporal evolution of C-S-H. In addition, the chemical compositions and silicate chain structure were comprehensively examined using BSE-EDS, <sup>27</sup>Al NMR, coupled with <sup>29</sup>Si NMR techniques. Our results demonstrate that AS addition accelerated C<sub>3</sub>S hydration, promoting the C-S-H nucleation and growth rate. This acceleration effect can be ascribed to (1) the accelerated dissolution of silicate phases at early stages, and (2) the formation of divergent C-S-H needles, providing more nucleation sites while mitigating impingement between adjacent C-(A)-S-H needles. Multiple characterizations confirmed the enhanced incorporation of aluminum into C-S-H, predominately at the bridging site. Notably, increasing AS content decreased the Si/Ca of the C-(A)-S-H and concurrently enhanced the aluminum incorporation. This compositional shift led to the formation of longer aluminosilicate chains and concomitant improvements in the hardness and elastic modulus of C-(A)-S-H. These findings offer valuable insights into AS-induced alterations in C-(A)-S-H within accelerated cement pastes, facilitating the deeper understanding of the role of C-(A)-S-H in strength development and long-term durability of shotcrete.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"199 ","pages":"Article 108052"},"PeriodicalIF":13.1,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145183117","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

Triaxial compressive behavior of high-strength strain-hardening fiber-reinforced cementitious composites: Fiber hybridization effect and constitutive relations 高强应变硬化纤维增强胶凝复合材料的三轴压缩性能：纤维杂化效应和本构关系

IF 13.1 1区工程技术

Cement and Concrete Research Pub Date : 2025-09-29 DOI: 10.1016/j.cemconres.2025.108049

Yanxin Hao , Xing Yin , Qinghua Li , Shilang Xu

{"title":"Triaxial compressive behavior of high-strength strain-hardening fiber-reinforced cementitious composites: Fiber hybridization effect and constitutive relations","authors":"Yanxin Hao , Xing Yin , Qinghua Li , Shilang Xu","doi":"10.1016/j.cemconres.2025.108049","DOIUrl":"10.1016/j.cemconres.2025.108049","url":null,"abstract":"<div><div>High-strength ultra-high toughness cementitious composites (HS-UHTCC) are advanced materials characterized by a combination of high compressive strength and remarkable tensile ductility. In this study, the triaxial compressive behavior of HS-UHTCC reinforced with hybrid steel-polyethylene fibers was experimentally investigated under confining pressures up to 120 MPa. The results demonstrated that HS-UHTCC specimens predominantly exhibited oblique shear failure under triaxial loading. With increasing confining pressure, the deviatoric strength, axial/ lateral strain at peak load all increased. Peak stress increased by 244.54 % and 276.20 % as confining pressure increased up to 120 MPa for various fiber hybridizations. Notably, when the confining pressure exceeded 100 MPa, the material ceased to soften and instead exhibited ductile behavior. Among the classical failure criteria studied, both the Power-Law and Willam-Warnke criteria successfully captured the triaxial strength envelope of HS-UHTCC. Finally, a pressure-dependent constitutive model was proposed to characterize the pre-peak hardening, post-peak softening, and brittle-to-ductile transition of HS-UHTCC.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"199 ","pages":"Article 108049"},"PeriodicalIF":13.1,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145183118","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

New insight into structural build-up modification by PCE superplasticizers during early C3A hydration PCE高效减水剂对C3A早期水化过程中结构堆积改性的新认识

IF 13.1 1区工程技术

Cement and Concrete Research Pub Date : 2025-09-27 DOI: 10.1016/j.cemconres.2025.108048

Kaidong Han , Tengfei Guo , Fei Meng , Yandong Guo , Xin Shu , Qianping Ran

{"title":"New insight into structural build-up modification by PCE superplasticizers during early C3A hydration","authors":"Kaidong Han , Tengfei Guo , Fei Meng , Yandong Guo , Xin Shu , Qianping Ran","doi":"10.1016/j.cemconres.2025.108048","DOIUrl":"10.1016/j.cemconres.2025.108048","url":null,"abstract":"<div><div>The much-complicated physical and chemical modification effects induced by PCE pose significant challenges in elucidating the role of C<sub>3</sub>A hydration in structural build-up. The research reveals a two-stage structural build-up in C<sub>3</sub>A-gypsum-CaCO₃ pastes, wherein varying dosages of PCE significantly influence the dynamics. The dominant driving force of structural build-up is the enhancement of colloidal interparticle bonds among bare surfaces. PCE weakens these bonds strength through steric hindrance and reduces the increment of number of these bonds due to its preferential adsorption on surfaces of ettringite formed in the solution. We identify two distinct structural build-up rates: a logarithmic growth rate (<em>G</em><sub>AFt</sub>) associated with the number of bonds between bare surfaces, and a linear growth rate (<em>G</em><sub>thix</sub>) linked to bond strength. As PCE preferentially adsorbs onto C<sub>3</sub>A particles, the reduction in <em>G</em><sub>AFt</sub> occurs more rapidly than that of <em>G</em><sub>thix</sub> with increasing surface coverage, which causes the dominant driving force during the first stage to shift from bond number to bond strength. Consequently, the strengthening of these bonds remains the predominant factor throughout the structural development with escalating PCE dosages, explaining why, at higher PCE levels, a coherent developmental pattern is observable across both stages.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"199 ","pages":"Article 108048"},"PeriodicalIF":13.1,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145181259","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-grade kaolinitic clays as SCMs for low-carbon cements and strength improvement by C-S-H gel nucleation seeding 低品位高岭石粘土作为低碳胶结剂和C-S-H凝胶成核播种提高强度的SCMs

IF 13.1 1区工程技术

Cement and Concrete Research Pub Date : 2025-09-24 DOI: 10.1016/j.cemconres.2025.108036

Diego Vallina , Isabel Santacruz , Alejandro Morales-Cantero , María Dolores Rodríguez-Ruiz , Ana Cuesta , Angeles G. De la Torre , Alessandro Dalla-Libera , Pere Borralleras , Sébastien Dhers , Peter Schwesig , Oliver Mazanec , Miguel A.G. Aranda

{"title":"Low-grade kaolinitic clays as SCMs for low-carbon cements and strength improvement by C-S-H gel nucleation seeding","authors":"Diego Vallina , Isabel Santacruz , Alejandro Morales-Cantero , María Dolores Rodríguez-Ruiz , Ana Cuesta , Angeles G. De la Torre , Alessandro Dalla-Libera , Pere Borralleras , Sébastien Dhers , Peter Schwesig , Oliver Mazanec , Miguel A.G. Aranda","doi":"10.1016/j.cemconres.2025.108036","DOIUrl":"10.1016/j.cemconres.2025.108036","url":null,"abstract":"<div><div>This study seeks to push the limits of LC<sup>3</sup>-50 binders by utilising low-grade kaolinite clays and C-S-H gel nucleation seeding. Four commercially-available kaolinite clays (i.e. kaolinite contents ~20 wt%) have been studied by X-ray fluorescence, X-ray powder diffraction and thermal analysis. The clays were thermally activated and milled to D<sub>v,50</sub> = 11 ± 2 μm. The activated clays showed low pozzolanic performances, as determined by ASTM C1897-20 standard. The heat flows ranged 200–230 J/g calcined clay and the bound waters 4.3–5.7 %. The LC<sup>3</sup>-50 pastes were characterised by calorimetry, X-ray powder diffraction and the Rietveld method, thermal analysis, and porosimetry to evaluate pozzolanic reactivity and the seeding effect.</div><div>LC<sup>3</sup> mortars, w/b = 0.40, have relatively low compressive strengths, especially at one day, but these values were increased by 64 % on average at one day by seeding. At 1 day, three LC<sup>3</sup> mortars showed 11 MPa which increased to 18–20 MPa by seeding. A fourth mortar showed a much higher compressive strength, 16 MPa, that increased to 23 MPa, by seeding. A tested concrete, w/b = 0.50, also showed a high increase of 37 % at 1 day. The improvements at 28 days were maintained but quantitatively lower, 12 and 14 % for the mortars and the concrete, respectively. Insights into the pozzolanic reactions and C-S-H seeding are obtained from the quantitative study of the pastes. For instance, it is proven the pozzolanic reaction at 1 day from the portlandite consumption. Also shown is the enhanced formation of carboaluminates when the strength enhancing admixture is added.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"199 ","pages":"Article 108036"},"PeriodicalIF":13.1,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145118032","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

Optimization of hydration kinetics, phase development and mechanical properties of CAC in mix with calcite by addition of sodium hydroxide and citric acid 氢氧化钠和柠檬酸对碳酸钙与方解石混合的水化动力学、相发育及力学性能的优化

IF 13.1 1区工程技术

Cement and Concrete Research Pub Date : 2025-09-20 DOI: 10.1016/j.cemconres.2025.108045

Pauline Rost , Christiane Rößler , Jürgen Neubauer , Friedlinde Goetz-Neunhoeffer

{"title":"Optimization of hydration kinetics, phase development and mechanical properties of CAC in mix with calcite by addition of sodium hydroxide and citric acid","authors":"Pauline Rost , Christiane Rößler , Jürgen Neubauer , Friedlinde Goetz-Neunhoeffer","doi":"10.1016/j.cemconres.2025.108045","DOIUrl":"10.1016/j.cemconres.2025.108045","url":null,"abstract":"<div><div>The influence of sodium hydroxide and citric acid on the hydration of a calcium aluminate cement – calcite mixture was investigated. Both the effect of the two additives individually and in combination were analysed. Sodium hydroxide accelerates the reaction, leads to dominant monocarbonate formation and higher inner strength. However, the workability is reduced. Citric acid retards the reaction, lowers the inner strength but has a positive influence on the workability. Furthermore, the main reaction with citric acid only begins when the concentration of citric acid in the pore solution drops below 125–115 mmol/l. In combination of both additives, NaOH improves the inner strength, whereas higher doses of citric acid improve the workability, whereby the dominant hydrate phase composition changes from monocarbonate to CAH<sub>10</sub>. In addition, it was observed that a higher degree of hydration within the first 24 h is associated with increased inner strength after 28 d.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"199 ","pages":"Article 108045"},"PeriodicalIF":13.1,"publicationDate":"2025-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145089157","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

Dispersant mechanisms in clays stabilized with MgO-based cement mgo基水泥稳定粘土中的分散剂机制

IF 13.1 1区工程技术

Cement and Concrete Research Pub Date : 2025-09-19 DOI: 10.1016/j.cemconres.2025.108040

Raphael Kuhn , Pietro Lura , Daniel Rentsch , Guillaume Habert , Ellina Bernard

{"title":"Dispersant mechanisms in clays stabilized with MgO-based cement","authors":"Raphael Kuhn , Pietro Lura , Daniel Rentsch , Guillaume Habert , Ellina Bernard","doi":"10.1016/j.cemconres.2025.108040","DOIUrl":"10.1016/j.cemconres.2025.108040","url":null,"abstract":"<div><div>Clay-based, low-CO₂ cement-stabilized materials offer a sustainable alternative to conventional building materials. This study examines the impact of various admixtures (Na-hexametaphosphate, Na‑carbonate, Na-silicate, Na-citrate, and Na-oxalate) on the rheological behavior of poured systems containing a MgO-metakaolin cement as stabilizer. The yield stress reduction follows the order Na-hexametaphosphate > Na-silicate > Na-citrate > Na-oxalate ≥ Na‑carbonate > no admixture. The zeta potential data with the solution analysis of the suspensions show that the adsorption of admixtures and/or a change in pH leads to a more negative surface, enhancing dispersion through electrostatic repulsion. Silicate and phosphate are not found in the suspension, <sup>29</sup>Si ssNMR indicates that silicate precipitates and polymerizes most likely as M-S-H. The phosphates are most likely adsorbed onto particles with opening of the phosphate rings observed by <sup>31</sup>P NMR. The anionic charge density of adsorbed polyphosphates was calculated and linked to the decreased colloid sizes observed with increasing Na-hexametaphosphate concentration.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"199 ","pages":"Article 108040"},"PeriodicalIF":13.1,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145089149","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

Reduction of drying shrinkage via C-S-H densification: The role of early-age thermal history 通过C-S-H致密化减少干燥收缩：早期热历史的作用

IF 13.1 1区工程技术

Cement and Concrete Research Pub Date : 2025-09-19 DOI: 10.1016/j.cemconres.2025.108037

Yuto Kanda , Ryo Kurihara , Ippei Maruyama

引用次数: 0