Cement and Concrete Research最新文献

Repeatability and reproducibility challenges of isothermal heat flow calorimetry with in situ mixing

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

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

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

In-situ XRD study of the effects of amino acids on the carbonation kinetics of cementitious calcium silicates

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-03-25 DOI: 10.1016/j.cemconres.2025.107879

Ziyu Chen , Tian Zhang , Yuxiang Wu , Ian Madsen , Jisheng Ma , Kwesi Sagoe-Crentsil , Adrian Neild , Wenhui Duan

{"title":"In-situ XRD study of the effects of amino acids on the carbonation kinetics of cementitious calcium silicates","authors":"Ziyu Chen , Tian Zhang , Yuxiang Wu , Ian Madsen , Jisheng Ma , Kwesi Sagoe-Crentsil , Adrian Neild , Wenhui Duan","doi":"10.1016/j.cemconres.2025.107879","DOIUrl":"10.1016/j.cemconres.2025.107879","url":null,"abstract":"<div><div>The carbonation of cementitious calcium silicates, specifically tricalcium silicate (C₃S) and dicalcium silicate (C₂S), is crucial for Carbon Capture and Utilization (CCU) in reducing CO₂ emissions in the cement and concrete industry. Controlling these reactions, including the rate and phase evolution necessary for producing desirable carbonated products, poses significant challenges. A lack of continuous kinetic data has impeded the understanding of the mechanisms behind carbonation and its optimization to enhance efficiency. This study explores the effects of four amino acids—glycine, L-arginine, sarcosine, and <span>l</span>-serine—on the carbonation of calcium silicate using in-situ XRD for real-time data collection. It identified a three-stage carbonation process starting with an induction period. The presence of specific amino acids encouraged the formation of stable vaterite and denser microstructures, indicating their potential to enhance the mechanical properties and durability of cementitious materials.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"193 ","pages":"Article 107879"},"PeriodicalIF":10.9,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143688027","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

Dual dynamic regulation mechanism of trace calcium phosphate on hydration of cementitious materials and optimization of pore structure 微量磷酸钙对胶凝材料水化和孔结构优化的双重动态调节机制

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-03-25 DOI: 10.1016/j.cemconres.2025.107875

Lei Wu , Jin Zhong , Zhe Sun , Yan Cao

引用次数: 0

Novel strategies for ultra-early strengthening of shotcrete: Stage-wise kinetic control of hydration products

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-03-25 DOI: 10.1016/j.cemconres.2025.107880

Hui Xie , Xin Liu , Haochuan Wang , Zhenqi Yu , Lijing Shao , Wei Wang , Jinxiang Hong , Chong Wang , Pan Feng

{"title":"Novel strategies for ultra-early strengthening of shotcrete: Stage-wise kinetic control of hydration products","authors":"Hui Xie , Xin Liu , Haochuan Wang , Zhenqi Yu , Lijing Shao , Wei Wang , Jinxiang Hong , Chong Wang , Pan Feng","doi":"10.1016/j.cemconres.2025.107880","DOIUrl":"10.1016/j.cemconres.2025.107880","url":null,"abstract":"<div><div>The use of aluminum sulfate (Al<sub>2</sub>(SO<sub>4</sub>)<sub>3</sub>)-based alkali-free accelerators in shotcrete often impeded tricalcium silicate (C<sub>3</sub>S) hydration, leading to poor ultra-early strength development. To address this, a novel stage-wise kinetic control strategy was proposed to regulate the sequential formation of ettringite and C-S-H gel through the delayed addition of C-S-H nano seeds. The dosage of C-S-H nano seeds, delayed time, addition sequence of Al<sub>2</sub>(SO<sub>4</sub>)<sub>3</sub> and C-S-H nano seeds were carefully examined in this study, and the effects of addition sequence on the hydration kinetic, hydration products, and pore structure of cement pastes were systematically investigated. Results demonstrated a significant enhancement in 6 h compressive strength, achieving a 35% increase when C-S-H nano seeds (4% dosage) were added 1 h after initial mixing compared to simultaneous addition. Hydration heat, XRD, TG, SEM, and BSE-EDS analyses revealed that the delayed addition promoted C<sub>3</sub>S hydration at later stages by staggering intensive ettringite formation and C-S-H gel precipitation, mitigating competition for calcium ions. This stage-wise approach facilitated C-S-H gel integration into the pre-constructed porous ettringite skeleton, refining the pore structure and enhancing ultra-early mechanical performance. These findings highlight an effective strategy to optimize hydration kinetics and strength development in shotcrete applications.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"193 ","pages":"Article 107880"},"PeriodicalIF":10.9,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143697332","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

Crystallization pressure in ASR expansion quantified by thermodynamic modeling and micromechanics

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-03-23 DOI: 10.1016/j.cemconres.2025.107878

Syrine Razki , Farid Benboudjema , Alexandra Bourdot , Sylvain Langlois , Amélie Fau , Fikri Hafid , Tulio Honorio

{"title":"Crystallization pressure in ASR expansion quantified by thermodynamic modeling and micromechanics","authors":"Syrine Razki , Farid Benboudjema , Alexandra Bourdot , Sylvain Langlois , Amélie Fau , Fikri Hafid , Tulio Honorio","doi":"10.1016/j.cemconres.2025.107878","DOIUrl":"10.1016/j.cemconres.2025.107878","url":null,"abstract":"<div><div>Establishing direct relations between alkali-silica reaction (ASR) expansion, crystallization pressure build-up, and phase assemblage changes is a critical step towards predictive modeling of ASR damage. To address this, we propose a strategy that combines thermodynamic modeling with micromechanics. First, we complete the thermodynamic database for ASR products, including nanocrystalline ASR-P1 data and improving the previous data for crystalline products. Phase assemblage is determined by accounting for cement hydration and amorphous silica dissolution kinetics. Crystallization pressure estimates are provided based on pore solution supersaturation with respect to ASR products. These phase assemblage and crystallization pressure estimates are then used as input for analytical micromechanical estimates of elastic properties degradation and macroscopic expansion. The model strategy that integrates damage considerations and the gel-like nature of ASR-P1 provides a better comparison with experimental results.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"193 ","pages":"Article 107878"},"PeriodicalIF":10.9,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143675499","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

A thermo-hygro model to determine the factors dictating cold joint formation in 3D printed concrete

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-03-21 DOI: 10.1016/j.cemconres.2025.107869

Michal Hlobil, Luca Michel, Mohit Pundir, David S. Kammer

引用次数: 0

Revealing the morphology of nano-ettringite in cement paste: A TEM study on the influence of polycarboxylate ether superplasticizers

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-03-20 DOI: 10.1016/j.cemconres.2025.107853

Olivia Rindle , Florian Sixt , Liam Spillane , Elena Willinger , Torben Gädt

{"title":"Revealing the morphology of nano-ettringite in cement paste: A TEM study on the influence of polycarboxylate ether superplasticizers","authors":"Olivia Rindle , Florian Sixt , Liam Spillane , Elena Willinger , Torben Gädt","doi":"10.1016/j.cemconres.2025.107853","DOIUrl":"10.1016/j.cemconres.2025.107853","url":null,"abstract":"<div><div>Ettringite forms directly after Portland cement is mixed with water. Polycarboxylate ether-type superplasticizers can stabilize nano-ettringite particles in the pore solution and modify ettringite formation. It was previously impossible to isolate the nano-ettringite from the cement pore solution at commonly used water-to-cement (w/c) ratios of 0.5 and lower. Therefore, the exact morphology of ettringite in the pore solution has not been systematically studied. This paper presents a novel method for obtaining nano-ettringite from cement paste by centrifugation with a high-density liquid. Ettringite was isolated at three different water-to-cement ratios (0.3, 0.4, and 0.5) and four dosages of a polycarboxylate ether-type superplasticizer (0.05%, 0.1%, 0.25%, and 0.4%). The size and morphology of the obtained ettringite particles were analyzed using transmission electron microscopy (TEM). The chemical composition and structure of ettringite were confirmed using electron energy loss spectroscopy, high-resolution TEM imaging, and X-ray diffraction. The ettringite particle size decreases as the superplasticizer dosage increases. As a result, the specific surface area at higher superplasticizer dosages increases from 39m<sup>2</sup>  g<sup>−1</sup>. In-situ calorimetry was used to measure the initial heat release and estimate the amount of ettringite formed. Since the initial heat did not change significantly with varying superplasticizer dosages, it suggests that the studied superplasticizer has a minor influence on the amount of ettringite at the considered concentrations. In summary, cement paste centrifugation using a high-density fluid allows the isolation of superplasticizer-stabilized nano-ettringite from cement paste. The method could be valuable for other studies dealing with the impact of ettringite morphology.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"193 ","pages":"Article 107853"},"PeriodicalIF":10.9,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143660436","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

Analysis of time-resolved water distribution and paramagnetic contents migration during alkali-activation process of Metakaolin using PD-MRI

IF 10.9 1区工程技术

Cement and Concrete Research Pub Date : 2025-03-18 DOI: 10.1016/j.cemconres.2025.107871

Zian Tang , Yuanrui Song , Wenyu Li

引用次数: 0