Cement and Concrete Research最新文献

{"title":"Impact of pore solution composition and superplasticizers on the interparticle forces and rheology of metakaolin suspensions","authors":"S. Real ,&nbsp;P. Bowen ,&nbsp;R. Moreno ,&nbsp;L. González-Panicello ,&nbsp;F. Puertas ,&nbsp;M. Hanafi ,&nbsp;M. Palacios","doi":"10.1016/j.cemconres.2025.107901","DOIUrl":"10.1016/j.cemconres.2025.107901","url":null,"abstract":"<div><div>This study focuses on the influence of pH, aqueous phase composition and superplasticizers on the particle interactions in pure metakaolin suspensions. It was found increasing pH up to 11 led to the decrease of the particle agglomeration due to the higher OH⁻ adsorption onto metakaolin particles, which increased the absolute zeta potential and generates higher electrostatic repulsive forces. Above pH = 11, a slight increase in zeta potential was observed and colloidal stability was retained. Metakaolin suspensions prepared in Na₂SO₄ or Ca(OH)₂ at pH = 13 did not agglomerate. However, the simultaneous presence of Ca²⁺ and SO₄²⁻, led to particle agglomeration, which was enhanced as Ca²⁺ concentration increased. The rise of Ca²⁺ concentration in suspensions containing Ca²⁺ and SO₄²⁻ also induced higher yield stress values in metakaolin suspensions. The addition of polycarboxylate ether (PCE) superplasticizers deagglomerated metakaolin particles and decreased yield stress values in agreement with interparticle force modelling.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"195 ","pages":"Article 107901"},"PeriodicalIF":10.9,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143863494","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":"Investigation and evaluation on early-age crack resistance of ultra-high performance seawater sea-sand concrete with non-metallic fiber","authors":"Kaidi Jiang ,&nbsp;Xin Wang ,&nbsp;Lining Ding ,&nbsp;Qingguo Ben ,&nbsp;Zhiyuan Chen ,&nbsp;Jian Ding ,&nbsp;Xia Liu ,&nbsp;Zhishen Wu","doi":"10.1016/j.cemconres.2025.107906","DOIUrl":"10.1016/j.cemconres.2025.107906","url":null,"abstract":"<div><div>Ultra-high performance seawater sea-sand concrete (UHP-SSC) exhibits outstanding mechanical properties, but the high cracking potential of UHP-SSC under restrained conditions should not be neglected. As steel fibers pose a corrosion risk when used in UHP-SSC, this study investigated and assessed the crack resistance of UHP-SSCs reinforced with non-metallic fibers. Cracking experiments were conducted employing a slab test, and the influencing mechanism was investigated based on macro-fiber pullout testing, pore structure determination, autogenous shrinkage (AS) monitoring, and uniaxial tensile testing. Results revealed that both the twisted texture of macro-fibers and micro-fiber incorporation into the matrix can enhance bonding. Adding fibers increased the macroporosity, except for the basalt fiber. The fiber's mechanical properties were positively related to the reduction in AS, and increase in tensile performance, crack resistance. Meanwhile, with a partial replacement of macro-fibers with micro-fibers, multi-scale hybrid non-metallic fibers exhibited better anti-cracking ability than UHP-SSC reinforced with straight steel fibers.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"195 ","pages":"Article 107906"},"PeriodicalIF":10.9,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143863496","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":"Deriving early hydration cement paste phase assemblage, microstructure development and elastic properties using thermodynamic simulation and multi-scale material modeling","authors":"Eva Jägle ,&nbsp;Jithender J. Timothy ,&nbsp;Daniel Jansen ,&nbsp;Alisa Machner","doi":"10.1016/j.cemconres.2025.107830","DOIUrl":"10.1016/j.cemconres.2025.107830","url":null,"abstract":"<div><div>Many hydration models focus on predicting the long-term hydration process and resulting material changes without specifically addressing early hydration within the first day. Here, we present a new approach for predicting early hydration cement paste phase assemblage, microstructure development and elastic properties by applying thermodynamic modeling and simulation as input to a multi-scale material model. Cement dissolution for implementation within the thermodynamic simulation is derived by fitting the five-parameter logistic function (5PL) to experimental data from quantitative X-ray diffraction. Results are compared with simulations using the modified Parrot &amp; Killoh model for cement dissolution. Further, the influence of variations in the calcium sulphate and calcite content of the initial cement phase assemblage is investigated accounting for errors in experimental determination. The proposed model for hydrating cement paste accounts for all phases predicted by the thermodynamic simulation output, two types of C-S-H, as well as concentric growth of hydrates from the surface of the clinker grains. The stiffness of the hydrating cement paste is derived by upscaling the microscopic properties using a multi-level continuum micromechanics homogenization scheme. Model predictions are compared with experimental results from penetration tests and ultrasonic Young’s modulus determination.</div><div>It is shown, that 5PL dissolution modeling in combination with thermodynamic simulation is able to describe early hydration cement phase alterations. The 5PL approach thereby captures initial ettringite formation and accurately describes portlandite precipitation. However, the results are highly dependent on the quality of the experimental data. The results further illustrate, how cement paste stiffness development can be derived by application of low-cost computational methods. The proposed approach enables investigations of state-of-the-art questions of cement hydration including the influence of individual hydrate phases on the solidification process.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"195 ","pages":"Article 107830"},"PeriodicalIF":10.9,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143863495","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":"Alkali-carbonate reaction in concrete - Microstructural consequences and mechanism of expansion","authors":"Andreas Leemann ,&nbsp;Beat Münch ,&nbsp;Barbara Lothenbach ,&nbsp;Ellina Bernard ,&nbsp;Cassandra Trottier ,&nbsp;Frank Winnefeld ,&nbsp;Leandro Sanchez","doi":"10.1016/j.cemconres.2025.107903","DOIUrl":"10.1016/j.cemconres.2025.107903","url":null,"abstract":"<div><div>A detailed microstructural investigation of a concrete expanding due to alkali‑carbonate reaction (ACR) shows that the cement paste adjacent to reactive aggregate particles is carbonated, which leads to a sulfur redistribution resembling internal sulfate attack. Simultaneously to dedolomitization, partial dissolution of illite occurs in aggregate particles leading to the formation of brucite, hydrotalcite, magnesium-silicate-hydrate (M-S-H) and calcium‑aluminum-silicate-hydrate (C-A-S-H), in addition to calcite and thus to a substantial increase in solid volume. Thermodynamic modelling indicates that the simultaneous presence of illite and dolomite can accelerate the reactions within the aggregates. No alkali-silica reaction (ASR) products are observed. Dolomite, illite and all reaction products display a negative ζ-potential at high pH generating repulsive forces during dedolomitization. Together with the substantial increase in molar volume, the concrete expansion can be mainly attributed to the solidification pressure of hydrotalcite and M-S-H formation.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"195 ","pages":"Article 107903"},"PeriodicalIF":10.9,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143854562","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":"Synthesis and thermodynamic data of acetate-containing giorgiosite – a novel hydrated magnesium carbonate","authors":"Hoang Nguyen ,&nbsp;Ellina Bernard ,&nbsp;Frank Winnefeld ,&nbsp;Barbara Lothenbach ,&nbsp;Paivo Kinnunen","doi":"10.1016/j.cemconres.2025.107902","DOIUrl":"10.1016/j.cemconres.2025.107902","url":null,"abstract":"<div><div>Organic additives play important roles in enhancing the formation of Mg‑carbonates and reaction kinetics in MgO-based cements. However, little is known about the influences of organics on the formation pathways of carbonate phases and whether organo-modified Mg‑carbonates exist. We found that acetate can be involved in the formation of a new hydrated magnesium carbonate phase containing acetate: [Mg₅(CO₃)_3.25(OH)₂(CH₃COO)_1.5·5H₂O]. In this work, the solubility product (log K_s0) of this phase was reported for the first time, while we also re-calculated the log K_s0 of artinite. This acetate-containing giorgiosite is rather stable at low temperature but artinite [Mg₂(OH)₂(CO₃)(H₂O)₃] and amorphous magnesium carbonates were observed at 20 °C while hydromagnesite [Mg₅(CO₃)₄(OH)₂·4H₂O], hydrated carbonate brucite (HCB) and amorphous magnesium carbonates were present at 50 and 80 °C. The work enables the potential of using organic additives in steering the reaction and formation of carbonates for better efficacy of carbon utilization and reactions in MgO-based cements.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"195 ","pages":"Article 107902"},"PeriodicalIF":10.9,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143851858","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":"Estimation of Young's modulus and compressive strength of cement using a solitary wave in granular crystals","authors":"Ahmed Z. Alkhaffaf ,&nbsp;Sangyoung Yoon ,&nbsp;Andreas Schiffer ,&nbsp;Tadahiro Kishida ,&nbsp;Chan Yeob Yeun ,&nbsp;Tae-Yeon Kim","doi":"10.1016/j.cemconres.2025.107904","DOIUrl":"10.1016/j.cemconres.2025.107904","url":null,"abstract":"<div><div>This study presents an in-depth examination of the sensitivity of highly nonlinear solitary waves (HNSWs) to variations in the curing period, the water-to-cement (w/c) ratio, and the mechanical properties of cement. Experimental results verify that the travel times and amplitude ratios of the HNSWs are highly sensitive to changes in curing time of 1 to 28 days, the w/c ratio of 0.3 to 0.6, the elastic modulus of 0.225 to 2.39 GPa, and the compressive strength of 8.24 to 95.32 MPa. Based on the predictions of a numerical model, we establish a simple mathematical relation connecting the modulus and compressive strength of the sample with the delay of the first (i.e., primary) reflected HNSW. The latter relation is employed to evaluate the elastic modulus and compressive strength of the cement samples with different curing periods and w/c ratios, showing good agreement with the results obtained from destructive tests.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"194 ","pages":"Article 107904"},"PeriodicalIF":10.9,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143847901","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":"Multiscale analysis on microstructural changes in hardened cement paste dried under different relative humidity levels: A comparison with cement paste containing water-dispersible polyurethane ether compound","authors":"Shingo Asamoto ,&nbsp;Keisuke Takahashi ,&nbsp;Naoki Sakamoto ,&nbsp;Tokio Sampei ,&nbsp;Kunio Matsui","doi":"10.1016/j.cemconres.2025.107896","DOIUrl":"10.1016/j.cemconres.2025.107896","url":null,"abstract":"<div><div>This study investigated microstructural changes in hardened cement paste with and without a water-dispersible polyurethane (PU) ether compound under varying relative humidity (RH) levels. The small-angle X-ray scattering technique was used to analyse the agglomeration, piling, and densification of calcium silicate hydrate (C-S-H) units. Mercury intrusion porosimetry and water vapour sorption isotherms were used to further characterise pore structures and surface areas, focusing on the C-S-H unit changes across different RH levels and the influence of PU. The presence of PU reduced variation in scattering profiles and subsequent calculated disc thickness at each RH, indicating the inhibition of C-S-H structural evolution during drying. These findings indicate less variation in the pore structure and surface area during the drying process than in the paste without PU. The length change isotherm of the cement paste with PU confirmed reduced shrinkage and hysteresis, which can be attributed to microstructural stabilisation.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"194 ","pages":"Article 107896"},"PeriodicalIF":10.9,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834499","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":"Shrinkage and carbonation of alkali-activated calcined clay-ground granulated blast furnace slag (GGBFS) concrete","authors":"Samuel De Carvalho Gomes ,&nbsp;Quang Dieu Nguyen ,&nbsp;Wengui Li ,&nbsp;Arnaud Castel","doi":"10.1016/j.cemconres.2025.107899","DOIUrl":"10.1016/j.cemconres.2025.107899","url":null,"abstract":"<div><div>This research investigates the influence of alkaline concentration and calcium content on the shrinkage mechanisms, carbonation resistance and reinforcement corrosion of alkali-activated concrete system composed of calcined clay and ground granulated blast furnace slag (GGBFS). An increase in Na₂O% led to an improvement in the mechanical performance, pore structure refinement, reducing both accelerated and natural carbonation. However, the increase in alkaline concentration generated a greater shrinkage for mixtures with a higher proportion of GGBFS; the opposite was observed for mixtures with calcined clay as the dominant precursor. The results of 1-year of total shrinkage shows that the concrete containing high calcined clay and Na₂O contents demonstrated the best performance. Importantly, there was no evidence of reinforcement corrosion observed after the carbonation front had reached the steel-concrete interface following 2 % CO₂ accelerated carbonation exposure. This was attributed to the high pH values measured in the carbonated region of the alkali-activated concrete.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"194 ","pages":"Article 107899"},"PeriodicalIF":10.9,"publicationDate":"2025-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143824006","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":"Automated experimentation for evaluating cement dispersant performance","authors":"Jae Hong Kim ,&nbsp;In Kuk Kang ,&nbsp;Tae Yong Shin ,&nbsp;Chan Kyu Park","doi":"10.1016/j.cemconres.2025.107895","DOIUrl":"10.1016/j.cemconres.2025.107895","url":null,"abstract":"<div><div>An automated experimental system enables precise evaluation of cement dispersant performance through rheological measurements of 230 mL mortar samples. Analysis of 129 mortar samples demonstrated comprehensive characterization of dispersant effects beyond traditional manual testing capabilities. Principal component analysis revealed distinct patterns in torque measurements, explaining the variance of the pattern and effectively capturing dispersant performance differences. The automated system achieved superior reproducibility with 7% coefficient of variance, which can be considered as the inherent variation of materials. Observation-informed learning extended the system's utility, successfully predicting flow and bleeding rate. Results confirmed superior performance of third-generation polycarboxylate dispersants while providing new insights into dosage-rheology relationships. This automated approach establishes a framework for more efficient and comprehensive evaluation of cement-based materials.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"194 ","pages":"Article 107895"},"PeriodicalIF":10.9,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143824005","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 nesquehonite and silica on magnesia-silicate‑carbonate cements","authors":"Zeyu Zhou ,&nbsp;Ellina Bernard ,&nbsp;Barbara Lothenbach","doi":"10.1016/j.cemconres.2025.107892","DOIUrl":"10.1016/j.cemconres.2025.107892","url":null,"abstract":"<div><div>Cements based on hydrated magnesium carbonates are an alternative binder system with high CO₂ sequestration ability. The present study examines the effect of silica, a by-product of MgO production from magnesium-silicate rocks, in MgO/nesquehonite binders. A high Mg/Si ratio of 3 was used to allow the formation of both the hydrous carbonate-containing brucite (HCB) phase and the magnesium silicate hydrate (M-S-H) phase. HCB formed within the first day. Its quantity was reduced during the formation of M-S-H and stabilized until the complete reaction of silica. Low quantities of nesquehonite, ≤10 wt%, accelerated M-S-H formation, while ≥16 wt% hindered it. CO₂ quantification showed that up to 12 g of CO₂ per 100 g dry cement could be sequestered. MgO/silica/nesquehonite mortars with 10 wt% of nesquehonite and a water/cement ratio of 0.65 exhibited overall good mechanical strength, achieving 23 MPa at 2 days and 36 MPa at 182 days.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"194 ","pages":"Article 107892"},"PeriodicalIF":10.9,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143816436","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}