Cement and Concrete Research最新文献_第2页

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 不同相对湿度干燥条件下硬化水泥浆体微观结构变化的多尺度分析：与含水分散聚氨酯醚化合物水泥浆体的比较

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-04-16 DOI: 10.1016/j.cemconres.2025.107896

Shingo Asamoto , Keisuke Takahashi , Naoki Sakamoto , Tokio Sampei , Kunio Matsui

{"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 , Keisuke Takahashi , Naoki Sakamoto , Tokio Sampei , 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}

引用次数: 0

Shrinkage and carbonation of alkali-activated calcined clay-ground granulated blast furnace slag (GGBFS) concrete 碱活化煅烧粘土-矿渣颗粒混凝土的收缩和碳化

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-04-13 DOI: 10.1016/j.cemconres.2025.107899

Samuel De Carvalho Gomes , Quang Dieu Nguyen , Wengui Li , Arnaud Castel

{"title":"Shrinkage and carbonation of alkali-activated calcined clay-ground granulated blast furnace slag (GGBFS) concrete","authors":"Samuel De Carvalho Gomes , Quang Dieu Nguyen , Wengui Li , 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 Na<sub>2</sub>O% 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 Na<sub>2</sub>O 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 % CO<sub>2</sub> 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}

引用次数: 0

Automated experimentation for evaluating cement dispersant performance 评价水泥分散剂性能的自动化实验

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-04-12 DOI: 10.1016/j.cemconres.2025.107895

Jae Hong Kim , In Kuk Kang , Tae Yong Shin , Chan Kyu Park

引用次数: 0

Effect of nesquehonite and silica on magnesia-silicate‑carbonate cements 珍珠岩和二氧化硅对镁-硅酸盐-碳酸盐胶结物的影响

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-04-11 DOI: 10.1016/j.cemconres.2025.107892

Zeyu Zhou , Ellina Bernard , Barbara Lothenbach

引用次数: 0

Probing the intrinsic mechanical properties of artinite using high-pressure X-ray diffraction for reactive MgO cement 用高压x射线衍射探测活性氧化镁水泥中artitinite的内在力学性能

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-04-11 DOI: 10.1016/j.cemconres.2025.107894

Ruoxi Yang, Jiaqi Li

引用次数: 0

Chloride ingress parameters derived from migration and diffusion tests for systems with calcined smectitic clay and limestone 由煅烧的蒙脱石粘土和石灰石系统的迁移和扩散试验得出的氯化物进入参数

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-04-08 DOI: 10.1016/j.cemconres.2025.107893

Maxime Ranger , Marianne Tange Hasholt , Ole Mejlhede Jensen

{"title":"Chloride ingress parameters derived from migration and diffusion tests for systems with calcined smectitic clay and limestone","authors":"Maxime Ranger , Marianne Tange Hasholt , Ole Mejlhede Jensen","doi":"10.1016/j.cemconres.2025.107893","DOIUrl":"10.1016/j.cemconres.2025.107893","url":null,"abstract":"<div><div>Cement pastes made with ternary binders containing Portland cement, calcined smectitic clay and limestone were subjected to chloride migration and diffusion. Microstructural changes due to chloride ingress were studied by mercury intrusion porosimetry and SEM back-scattered electron image analysis, while chemical changes were investigated via chloride binding isotherms complemented by thermogravimetric analysis, X-ray diffraction and SEM-EDS. Chloride binding parameters were taken as inputs in a chloride diffusion model, to process chloride profiles obtained in diffusion experiments.</div><div>Refinement of the pore structure was observed for pure Portland cement samples in migration. No changes were observed in diffusion, nor with ternary blends. Moreover, ternary blends lead to more chloride binding compared to Portland cement, mainly due to more Friedel's salt. Effective diffusion coefficients, purely linked to transport properties, obtained from migration and diffusion experiments agree well. Conversely, apparent diffusion coefficients may differ by a factor two. Implications regarding chloride ingress are discussed.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"194 ","pages":"Article 107893"},"PeriodicalIF":10.9,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791965","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

Hydration and strength of cement paste containing metastable vaterite derived from recycled concrete fines and CO2 含再生混凝土细粒和CO2的亚稳水灰岩水泥浆体的水化和强度

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-04-05 DOI: 10.1016/j.cemconres.2025.107891

Hamideh Mehdizadeh , Tung-Chai Ling

{"title":"Hydration and strength of cement paste containing metastable vaterite derived from recycled concrete fines and CO2","authors":"Hamideh Mehdizadeh , Tung-Chai Ling","doi":"10.1016/j.cemconres.2025.107891","DOIUrl":"10.1016/j.cemconres.2025.107891","url":null,"abstract":"<div><div>Alkaline solid wastes, such as recycled concrete fines, can integrate with CO<sub>2</sub> to produce high-purity vaterite CaCO<sub>3</sub> via leaching‑carbonation mineralization. This study aims to examine the stability and nucleation effects of the metastable vaterite relative to stable conventional calcite in cement paste systems. To better elucidate the underlying mechanisms, their influence in the pure C<sub>3</sub>S/C<sub>3</sub>A phase systems was also comparatively studied. The results indicate that vaterite accelerates the hydration rate of C<sub>3</sub>S and C<sub>3</sub>A phases, resulting in the formation of both crystalline and amorphous calcium silicate hydrates, as well as carbonate-Am phases, within the first 12 h of hydration. The spherical morphology of vaterite facilitates a more uniform distribution of hydration products, leading to particle encapsulation and reduced nucleation effects at later ages (> 7 days). Overall, vaterite blended cement pastes exhibit 40% higher early strength at 7 days and comparable long-term mechanical properties to those made with calcite.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"194 ","pages":"Article 107891"},"PeriodicalIF":10.9,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777122","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

Repeatability and reproducibility challenges of isothermal heat flow calorimetry with in situ mixing 原位混合等温热流量热法的重复性和再现性挑战

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-03-31 DOI: 10.1016/j.cemconres.2025.107872

Elisabeth John , Cordula Jakob , Ursula Pott , Mona Sando

{"title":"Repeatability and reproducibility challenges of isothermal heat flow calorimetry with in situ mixing","authors":"Elisabeth John , Cordula Jakob , Ursula Pott , Mona Sando","doi":"10.1016/j.cemconres.2025.107872","DOIUrl":"10.1016/j.cemconres.2025.107872","url":null,"abstract":"<div><div>Isothermal heat flow calorimetry evaluates heat development during binder reactions. It distinguishes between in situ calorimetry, where mixing occurs within the device, and ex situ calorimetry, involving externally mixed samples. Despite ex situ calorimetry being a standard method in binder research, in situ calorimetry is underutilized. This paper aims to promote its adoption by summarizing challenges related to repeatability and reproducibility and offering solutions. The initial section addresses repeatability issues caused by preventable errors, providing a structured guide for experimental design. It was found that water leakage had minimal impact, and sample size is crucial for data robustness. The second section examines operational challenges, revealing that frictional heating, affecting recorded heat, can be minimized with an optimized mixing protocol. The final part highlights that significant errors in measured data stem from signal delay and heat loss, offering methods to correct these issues for improved reproducibility in in situ calorimetric experiments.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"194 ","pages":"Article 107872"},"PeriodicalIF":10.9,"publicationDate":"2025-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143737214","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

Dedolomitization of dolostone filler: Modifying the course of Mg with SCM 白云石填料的脱白云化：用SCM改性镁的过程

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-03-31 DOI: 10.1016/j.cemconres.2025.107883

Antonela Di Salvo Barsi, Mónica A. Trezza, Edgardo F. Irassar

引用次数: 0

Degradation mechanisms of low-calcium fly ash-based geopolymer mortar in simulated aggressive sewer conditions 低钙粉煤灰基地聚合物砂浆在模拟恶劣下水道条件下的降解机理

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-03-29 DOI: 10.1016/j.cemconres.2025.107882

Piumika W. Ariyadasa , Allan C. Manalo , Weena Lokuge , Vasantha Aravienthan , Andreas Gerdes , Jonas Kaltenbach

{"title":"Degradation mechanisms of low-calcium fly ash-based geopolymer mortar in simulated aggressive sewer conditions","authors":"Piumika W. Ariyadasa , Allan C. Manalo , Weena Lokuge , Vasantha Aravienthan , Andreas Gerdes , Jonas Kaltenbach","doi":"10.1016/j.cemconres.2025.107882","DOIUrl":"10.1016/j.cemconres.2025.107882","url":null,"abstract":"<div><div>Alkali-activated geopolymers are increasingly studied as alternatives to Ordinary Portland Cement (OPC) concrete for use in challenging service environments. Low-calcium geopolymers have been advocated to mitigate Microbial-Induced Concrete Corrosion (MICC) in sewer pipes; however, their broader acceptance as a repair material for sewer rehabilitation remains to be established. This study evaluated the degradation mechanism of low-calcium fly ash-based geopolymer (FAGP) repair mortar under laboratory-simulated sewer conditions by exposing it to varying concentrations of sulphuric acid (pH 0.5, 1, and 4) for extended durations. The corrosion of the mortar samples was assessed based on visual changes, mass loss, residual mechanical strength, pore evolution, and ion transport over three exposure durations. Comparative analysis with OPC counterparts served as a benchmark. The degradation of FAGP and OPC due to acid exposure appears to escalate with both acid concentration and exposure. However, FAGP displayed superior performance by maintaining their shape and retaining approximately 30% of mechanical strength even after 3000 h of exposure under highly aggressive sewer conditions at pH 0.5. In contrast, OPC fails to endure acid exposure beyond 2000 h. The loss of matrix integrity primarily stems from ion leaching, supported by Scanning Electron Microscopy and Mercury Intrusion Porosimetry analysis, which revealed the creation of intrinsic pores facilitating the ingress of sulphate ions into the matrix. X-Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) Spectroscopy patterns indicate no significant phase alterations, confirming this phenomenon. In conclusion, this study demonstrated that FAGP mortar is more resilient and durable in mild to aggressive sewer conditions than OPC.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"194 ","pages":"Article 107882"},"PeriodicalIF":10.9,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725578","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