Cement and Concrete Research最新文献

{"title":"Can iron-doped calcium aluminates activate ternesite hydration?","authors":"Yangrui Li ,&nbsp;Yanfei Yue ,&nbsp;Jueshi Qian ,&nbsp;Yun Bai","doi":"10.1016/j.cemconres.2025.108085","DOIUrl":"10.1016/j.cemconres.2025.108085","url":null,"abstract":"<div><div>The hydration inertness of ternesite (C₅S₂Š) is the primary barrier to the promotion of Ternesite-Ye'elimite Cement (TYC). This study investigated the potential of iron-doped calcium aluminates to activate the hydration of TYC systems, with particular focus on their roles in enhancing the reactivity of C₅S₂Š. Three types of calcium aluminates, viz. orthorhombic ye'elimite (C₄A₃Š), iron-doped cubic ye'elimite (C₄(A,F)₃Š) and ferrite (C₄AF), as well as C₅S₂Š were synthesized in the laboratory. These four minerals, and three blends formulated by mixing each calcium aluminate with C₅S₂Š, were mixed with water to obtain a total of seven paste mixtures. Their hydration processes were examined using ICC, XRD, FT-IR, TG, and pore solution chemistry analysis to elucidate the influence of iron-doped calcium aluminates (C₄(A,F)₃Š and C₄AF) on the hydration reactivity of C₅S₂Š and the corresponding mechanisms. Results show that C₄(A,F)₃Š significantly enhanced the hydration reactivity of C₅S₂Š by providing reactive amorphous (A,F)H₃ to consume gypsum from the hydration of C₅S₂Š. Evidently, iron doping exhibited a gypsum-like acceleration effect on the hydration of C₅S₂Š + C₄(A,F)₃Š system, albeit through a distinct chemical pathway. However, C₄AF demonstrated quite limited effect on the C₅S₂Š + C₄AF system, due to the gradual formation of a gel layer on the C₄AF surface that restricted further hydration.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"200 ","pages":"Article 108085"},"PeriodicalIF":13.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145447421","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}

{"title":"Effect of ionic doping on the structure and reactivity of Portland cement tricalcium silicate","authors":"L.C. Queiroz ,&nbsp;W.S. Barbosa ,&nbsp;M.D.S. de Lima ,&nbsp;I.N.L. Paes ,&nbsp;A.P. Kirchheim ,&nbsp;C.P. Bergmann","doi":"10.1016/j.cemconres.2025.108064","DOIUrl":"10.1016/j.cemconres.2025.108064","url":null,"abstract":"<div><div>Doping during Portland cement clinker synthesis significantly influences the stabilization and reactivity of tricalcium silicate (C₃S) polymorphs. Therefore, this study investigates the effect of MgO, ZnO, and TiO₂ doping (at 0.5 and 1.0 wt%) on the structural and hydration behavior of C₃S. Synthesis was performed at 1500 °C for six hours, followed by characterization using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) surface area analysis, and isothermal calorimetry. To further assess the catalytic effects of dopant ions on C₃S hydration, higher doping levels (4.0 and 8.0 wt%) were also evaluated. The results show that doping promotes stabilization of the T3, M1, and M3 C₃S polymorphs. Among the dopants, MgO-enhanced phases exhibited higher intrinsic reactivity. However, despite this increased reactivity, hydration rates were reduced across all systems due to a dual effect: catalytic interactions with the hydration products and the formation of a physical barrier by excess dopant. These findings provide new insights into the design of doped clinker systems for tailored hydration performance.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"200 ","pages":"Article 108064"},"PeriodicalIF":13.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145383654","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}

{"title":"New insights into the role of superplasticizer addition time on yield stress of cementitious materials","authors":"Shengnan Sha,&nbsp;Sirajuddin Moghul,&nbsp;Robert J. Flatt","doi":"10.1016/j.cemconres.2025.108089","DOIUrl":"10.1016/j.cemconres.2025.108089","url":null,"abstract":"<div><div>The timing of superplasticizer addition is known to impact both the yield stress and hydration kinetics of cementitious systems. Recent results demonstrate that these changes can be directly related to changes in the specific surface area of the cement paste. As this results from a change in hydrate morphology, in particular ettringite, two main reasons may explain yield stress changes in relation to addition time.</div><div>On the one hand, these may result from changes in adsorption. On the other hand, they may be due to changes in the maximum packing of the cement paste. To examine both scenarios, we have applied the YODEL, a Yield Stress mODEL that has been recognized as an effective model for predicting the yield stress of cement-based materials.</div><div>By doing this, we could evaluate the relative roles of changes in adsorption and of maximum packing in cement-limestone pastes. Results indicate that, in the range of yield stresses and volume fractions measurable in our experiments, changes in adsorption, rather than variations in maximum packing, are the primary difference between direct and delayed addition.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"200 ","pages":"Article 108089"},"PeriodicalIF":13.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145598619","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}

{"title":"Effect of the hydration temperature between 110 and 190 ∘C on the microstructure of Class G cement: Phase composition, pore structure and C–S–H chemistry","authors":"Axelle Alavoine ,&nbsp;Math Lecomte ,&nbsp;Mickael Saillio ,&nbsp;Myriam Duc ,&nbsp;Siavash Ghabezloo","doi":"10.1016/j.cemconres.2025.108093","DOIUrl":"10.1016/j.cemconres.2025.108093","url":null,"abstract":"<div><div>This study examines the microstructural evolution and changes in the properties of C–S–H in a cement paste hydrated at elevated temperatures ranging from 110 to 190 <span><math><msup><mrow></mrow><mrow><mo>∘</mo></mrow></msup></math></span>C. Using a simple slurry formulation composed only of Class G cement and water, the material’s evolution was quantitatively investigated through a multi-technique approach, including mechanical testing (UCT), microstructural analysis (MIP), and chemical characterization (TGA and XRD). The results reveal two key mechanisms driving the observed strength loss: (1) a significant increase in porosity and pore size over time, leading to microstructural coarsening, and (2) the formation of denser crystalline phases with higher C/S ratios (over 2). Estimations of the C/S ratio and density of the amorphous C–S–H indicate its progressive decalcification and densification, with the lowest C/S values observed at the highest curing temperatures. This work extends previous studies on the quantitative characterization of Class G cement paste hydrated between 7 and 90 <span><math><msup><mrow></mrow><mrow><mo>∘</mo></mrow></msup></math></span>C (Bahafid et al., 2017, 2018), offering a comprehensive understanding of microstructural evolution over a broad temperature range - from 7 to 190 <span><math><msup><mrow></mrow><mrow><mo>∘</mo></mrow></msup></math></span>C - during hydration.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"200 ","pages":"Article 108093"},"PeriodicalIF":13.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145575225","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}

{"title":"A novel defoaming technology for cement paste by using power ultrasound treatment","authors":"Guangqi Xiong ,&nbsp;Zheng Fang ,&nbsp;Yuanliang Ren ,&nbsp;Xiaolong Jia ,&nbsp;Hongkuang Luo ,&nbsp;Jiaxin Yang ,&nbsp;Bo Ran ,&nbsp;Shuai Zhou ,&nbsp;Chong Wang","doi":"10.1016/j.cemconres.2025.108072","DOIUrl":"10.1016/j.cemconres.2025.108072","url":null,"abstract":"<div><div>To address the limitations of conventional vibration in removing microbubbles from cement paste, this study introduces power ultrasound as a novel defoaming technology and investigates its effectiveness and mechanism. Experiments conducted at a water-to-cement ratio of 0.50, with or without air-entraining agents, and demonstrated that ultrasound treatment effectively eliminated microbubbles, as confirmed by ¹H NMR and FBRM analyses. Compared to controls, treated batches exhibited increases in compressive strength of 17.1 % and 7.3 % at 3 days, and 6.8 % and 3.8 % at 28 days. Modeling indicates that bubbles move towards the pressure node once ultrasound is applied, and whether bubble coalescence occurs is primarily governed by the secondary Bjerknes force. Coalesced bubbles will then rise due to increased buoyancy. These findings highlight the significant potential of power ultrasound as an innovative and efficient defoaming technology for cement-based materials, offering improved microstructure and mechanical performance.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"200 ","pages":"Article 108072"},"PeriodicalIF":13.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145434840","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}

{"title":"3D printed concrete with recycled coarse aggregate: Freeze–thaw resistance assessment and damage mechanisms","authors":"Huawei Liu ,&nbsp;Yaxin Tao ,&nbsp;Chao Zhu ,&nbsp;Chao Liu ,&nbsp;Yifei Wang ,&nbsp;Jiao Yun ,&nbsp;Yukun Zhang","doi":"10.1016/j.cemconres.2025.108095","DOIUrl":"10.1016/j.cemconres.2025.108095","url":null,"abstract":"<div><div>3D printed concrete exhibits significant durability issues under freeze–thaw (F–T) conditions due to its unique pore structure, restricting its widespread application in cold regions. In this study, the frost resistance of 3D printed recycled aggregate concrete (3DPRAC) was systematically evaluated at different recycled coarse aggregate (RCA) replacement ratios (0 %, 50 %, and 100 %), and the underlying damage mechanisms induced by F–T cycles were elucidated. Results indicated that the frost resistance of 3DPRAC was notably inferior to cast concrete and further deteriorated nonlinearly with increasing RCA replacement ratios. Ellipsoidal pores within 3DPRAC facilitated ice crystal formation, accelerating crack initiation and propagation. Damage originated from the porous old mortar in RCA and dual interfacial transition zones, while ultimate failure was dominated by a multi-interface and pore structure defect system jointly formed by RCA and printed structure. This research provides theoretical insights for durability design of 3D printed concrete structures in cold-region applications.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"200 ","pages":"Article 108095"},"PeriodicalIF":13.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145613721","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}

{"title":"Tailoring neutron-shielding boron-metakaolin geopolymers with B4C filler: Surfactant-driven interfacial and microstructural control","authors":"Xiaobo Niu ,&nbsp;Yogarajah Elakneswaran ,&nbsp;Ryosuke Kikuchi ,&nbsp;Ang Li ,&nbsp;Sivasubramaniam Seralathan ,&nbsp;Yoshihisa Hiraki ,&nbsp;Junya Sato ,&nbsp;Takeshi Osugi ,&nbsp;Takashi Kamiyama ,&nbsp;Brant Walkley","doi":"10.1016/j.cemconres.2025.108096","DOIUrl":"10.1016/j.cemconres.2025.108096","url":null,"abstract":"<div><div>The incorporation of boron (B) as a neutron absorber into metakaolin-based geopolymers for the remediation of radioactive debris following nuclear accidents has attracted considerable attention. In this study, boron carbide (B₄C) was employed as a functional filler, while cetyltrimethylammonium bromide (CTAB) acted as both a dispersant and a stabiliser to enhance the neutron shielding properties of metakaolin-based geopolymers. Although the addition of B₄C improved processability via a “roller-ball” effect and had no discernible impact on the geopolymerisation process, its weakly polar, negatively charged surface led to the formation of a loose, weak-shell interfacial transition zone (ITZ) between the filler and the matrix, thereby reducing mechanical strength and chemical stability. In contrast, CTAB self-assembled into an interdigitated monolayer on the B₄C surface, reversing its surface charge to positive and promoting its uniform dispersion within the matrix. While CTAB slightly inhibited the dissolution of metakaolin, it preferentially interacted with B₄C, thereby mitigating the adverse effects on the geopolymerisation process. Moreover, CTAB promoted gelation within the ITZ surrounding B₄C, facilitating the development of a dense, potassium-deficient, yet electrostatically stabilised microstructure. This synergistic interaction enhanced interfacial bonding between the filler and the matrix, enabled efficient stress transfer, and significantly improved mechanical performance and chemical stability. Furthermore, the B₄C–CTAB-modified geopolymers demonstrated enhanced neutron shielding performance. Overall, this work offers a promising approach for engineering high-performance, multifunctional geopolymer composites for nuclear and environmental applications.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"200 ","pages":"Article 108096"},"PeriodicalIF":13.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145609236","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}

{"title":"Co-calcination of limestone and clay enhances the performance of limestone calcined clay cement (LC3)","authors":"Oluwadamilare Charles Adesina ,&nbsp;Sahil Surehali ,&nbsp;Avinaya Tripathi ,&nbsp;Kayla Lauren Lee ,&nbsp;Bryan K. Aylas-Paredes ,&nbsp;Aditya Kumar ,&nbsp;Narayanan Neithalath","doi":"10.1016/j.cemconres.2025.108069","DOIUrl":"10.1016/j.cemconres.2025.108069","url":null,"abstract":"<div><div>Limestone-calcined clay cements (<span><math><msup><mi>LC</mi><mn>3</mn></msup></math></span>) reduce the environmental impact of cement production and accelerate the industry transition toward carbon neutrality. While conventional <span><math><msup><mi>LC</mi><mn>3</mn></msup></math></span> with 50% clinker replacement (<span><math><msup><mi>LC</mi><mn>3</mn></msup></math></span>-50) demonstrate long-term performance comparable to ordinary Portland cement (OPC) in concrete, early-age performance is generally compromised. This study explores for the first time, joint thermal treatment—that is, co-calcination—of limestone (LS) and bulk kaolinitic clay in mass ratios of 1:1 to 1:4 under a calcination regime specifically designed to ensure activation of the clay mineral. The co-calcination converts a small fraction of LS to metastable CaO, thus providing an additional reactive calcium source during hydration. Microstructural, kinetic, and thermodynamic studies on systems with 50% clinker replacement are used to quantify enhanced early-stage in situ formation of portlandite, which promotes the precipitation of <span><math><mi>C</mi><mo>−</mo><mfenced><mi>A</mi></mfenced><mo>−</mo><mi>S</mi><mo>−</mo><mi>H</mi></math></span> and carboaluminate hydrates, that refine the pore structure and improve early-age strength—even in systems with low calcined clay content. A performance-efficiency index is used to indicate the improved mechanical and environmental performance of co-calcined blends as compared to traditional <span><math><msup><mi>LC</mi><mn>3</mn></msup></math></span>. The approach offers a potential pathway to achieving higher clinker substitution levels.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"200 ","pages":"Article 108069"},"PeriodicalIF":13.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145340212","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}

{"title":"A high-efficiency neuroevolution potential for tobermorite and calcium silicate hydrate systems with ab initio accuracy","authors":"Xiao Xu ,&nbsp;Shijie Wang ,&nbsp;Haifeng Qin ,&nbsp;Zhiqiang Zhao ,&nbsp;Zheyong Fan ,&nbsp;Zhuhua Zhang ,&nbsp;Hang Yin","doi":"10.1016/j.cemconres.2025.108091","DOIUrl":"10.1016/j.cemconres.2025.108091","url":null,"abstract":"<div><div>Tobermorite and Calcium Silicate Hydrate (C-S-H) systems are indispensable cement materials but still lack a satisfactory interatomic potential with both high accuracy and high computational efficiency for better understanding their mechanical performance. Here, we develop a Neuroevolution Machine Learning Potential (NEP) with Ziegler-Biersack-Littmark hybrid framework for tobermorite and C-S-H systems, which conveys unprecedented efficiency in molecular dynamics simulations with substantially reduced training datasets. Our NEP model achieves prediction accuracy comparable to DFT calculations using just around 400 training structures, significantly fewer than other existing machine learning potentials trained for tobermorite. Critically, the GPU-accelerated NEP computations enable scalable simulations of large tobermorite systems, reaching several thousand atoms per GPU card with high efficiency. We demonstrate the NEP's versatility by accurately predicting mechanical properties, phonon density of states, and thermal conductivity of tobermorite. Furthermore, we extend the NEP application to large-scale simulations of amorphous C-S-H, highlighting its potential for comprehensive analysis of structural and mechanical behaviors under various realistic conditions.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"200 ","pages":"Article 108091"},"PeriodicalIF":13.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145554904","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}

{"title":"Thermodynamic properties of ternesite (Ca5(SiO4)2SO4) from 0 K up to clinkering temperatures","authors":"Chancel Mawalala Moundounga ,&nbsp;Wahab Abdul ,&nbsp;Alexander Pisch ,&nbsp;Gavin B.G. Stenning ,&nbsp;Cecilia Pesce ,&nbsp;Theodore Hanein","doi":"10.1016/j.cemconres.2025.108090","DOIUrl":"10.1016/j.cemconres.2025.108090","url":null,"abstract":"<div><div>Ternesite (Ca₅(SiO₄)₂SO₄) is a cementitious phase that can be found in the production of calcium sulfoaluminate (CSA) based cements and other alternative binders. Ternesite has received interest due to its potential hydraulic reactivity (under certain conditions) whilst having a low temperature of formation. Despite this, the ternesite phase is not thermodynamically well understood, reducing the ability to accurately model its formation, stability and phase co-existence in clinker. In this work, pure ternesite was synthesised and the high temperature heat content (874–1174 K) and low temperature heat capacity (2−302<em>K</em>) was measured using drop calorimetry and PPMS respectively. These data were then combined with enthalpy of formation results from DFT and previous experiments to model the thermodynamics properties of ternesite using the 3rd generation CALPHAD function. This allows for a single function to describe the thermodynamic properties of ternesite for use in extending existing thermodynamic databases as part of predictive calculations at a temperature range from 0 K to above the clinkering temperature.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"200 ","pages":"Article 108090"},"PeriodicalIF":13.1,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145567521","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}