{"title":"MCM-41改性水泥浆体在热载荷作用下的微观结构变化及孔径分布建模","authors":"Maciej Szeląg, Patryk Rumiński, Rafał Panek","doi":"10.1016/j.cemconcomp.2025.105930","DOIUrl":null,"url":null,"abstract":"<div><div>This study examines the effects of highly reactive, mesoporous MCM-41 silica on the thermal resistance and microstructural stability of Portland cement paste (CP). The motivation is to enhance cement composites (CC) properties using supplementary cementitious materials (SCMs), addressing environmental challenges from global cement production. The research involved modifying CP with 0–2 wt% MCM-41 and subjecting it to thermal loads from 20 °C to 700 °C. Evaluations included compressive and tensile strengths, density, water absorption, and shrinkage. Characterization techniques like X-ray diffraction (XRD) and mercury intrusion porosimetry (MIP) analysed phase composition and pore distribution. Results showed that MCM-41 significantly improved compressive strength, with a 26.9 % increase at 0.75 wt% content. Tensile strength also improved up to 33.8 % for 0.25–1 wt% MCM-41 content. Thermal stability tests indicated enhanced performance in the 200–500 °C range by reducing microcrack formation. XRD analysis revealed that MCM-41 influenced the phase composition, particularly delaying the thermal decomposition of portlandite and enhancing the stability of calcium silicate hydrates (CSH). Microstructural analysis revealed a denser, more cohesive cement matrix with reduced water absorption and shrinkage, enhancing durability. Additionally, MIP studies showed that MCM-41 contributed to a finer pore structure, improving the overall mechanical properties despite increased porosity. To supplement the findings, peak models have been tested to assess the ability to numerically predict pore size distribution of thermally loaded CP. Thus, MCM-41 is effective for improving the thermal and mechanical properties of CP, offering potential for applications in thermally stressed environments, contributing to more sustainable construction materials.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105930"},"PeriodicalIF":10.8000,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Microstructure transformation of MCM-41 modified cement paste subjected to thermal load and modelling of its pore size distribution\",\"authors\":\"Maciej Szeląg, Patryk Rumiński, Rafał Panek\",\"doi\":\"10.1016/j.cemconcomp.2025.105930\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>This study examines the effects of highly reactive, mesoporous MCM-41 silica on the thermal resistance and microstructural stability of Portland cement paste (CP). The motivation is to enhance cement composites (CC) properties using supplementary cementitious materials (SCMs), addressing environmental challenges from global cement production. The research involved modifying CP with 0–2 wt% MCM-41 and subjecting it to thermal loads from 20 °C to 700 °C. Evaluations included compressive and tensile strengths, density, water absorption, and shrinkage. Characterization techniques like X-ray diffraction (XRD) and mercury intrusion porosimetry (MIP) analysed phase composition and pore distribution. Results showed that MCM-41 significantly improved compressive strength, with a 26.9 % increase at 0.75 wt% content. Tensile strength also improved up to 33.8 % for 0.25–1 wt% MCM-41 content. Thermal stability tests indicated enhanced performance in the 200–500 °C range by reducing microcrack formation. XRD analysis revealed that MCM-41 influenced the phase composition, particularly delaying the thermal decomposition of portlandite and enhancing the stability of calcium silicate hydrates (CSH). Microstructural analysis revealed a denser, more cohesive cement matrix with reduced water absorption and shrinkage, enhancing durability. Additionally, MIP studies showed that MCM-41 contributed to a finer pore structure, improving the overall mechanical properties despite increased porosity. To supplement the findings, peak models have been tested to assess the ability to numerically predict pore size distribution of thermally loaded CP. Thus, MCM-41 is effective for improving the thermal and mechanical properties of CP, offering potential for applications in thermally stressed environments, contributing to more sustainable construction materials.</div></div>\",\"PeriodicalId\":9865,\"journal\":{\"name\":\"Cement & concrete composites\",\"volume\":\"157 \",\"pages\":\"Article 105930\"},\"PeriodicalIF\":10.8000,\"publicationDate\":\"2025-01-09\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Cement & concrete composites\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0958946525000125\",\"RegionNum\":1,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CONSTRUCTION & BUILDING TECHNOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cement & concrete composites","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0958946525000125","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}
Microstructure transformation of MCM-41 modified cement paste subjected to thermal load and modelling of its pore size distribution
This study examines the effects of highly reactive, mesoporous MCM-41 silica on the thermal resistance and microstructural stability of Portland cement paste (CP). The motivation is to enhance cement composites (CC) properties using supplementary cementitious materials (SCMs), addressing environmental challenges from global cement production. The research involved modifying CP with 0–2 wt% MCM-41 and subjecting it to thermal loads from 20 °C to 700 °C. Evaluations included compressive and tensile strengths, density, water absorption, and shrinkage. Characterization techniques like X-ray diffraction (XRD) and mercury intrusion porosimetry (MIP) analysed phase composition and pore distribution. Results showed that MCM-41 significantly improved compressive strength, with a 26.9 % increase at 0.75 wt% content. Tensile strength also improved up to 33.8 % for 0.25–1 wt% MCM-41 content. Thermal stability tests indicated enhanced performance in the 200–500 °C range by reducing microcrack formation. XRD analysis revealed that MCM-41 influenced the phase composition, particularly delaying the thermal decomposition of portlandite and enhancing the stability of calcium silicate hydrates (CSH). Microstructural analysis revealed a denser, more cohesive cement matrix with reduced water absorption and shrinkage, enhancing durability. Additionally, MIP studies showed that MCM-41 contributed to a finer pore structure, improving the overall mechanical properties despite increased porosity. To supplement the findings, peak models have been tested to assess the ability to numerically predict pore size distribution of thermally loaded CP. Thus, MCM-41 is effective for improving the thermal and mechanical properties of CP, offering potential for applications in thermally stressed environments, contributing to more sustainable construction materials.
期刊介绍:
Cement & concrete composites focuses on advancements in cement-concrete composite technology and the production, use, and performance of cement-based construction materials. It covers a wide range of materials, including fiber-reinforced composites, polymer composites, ferrocement, and those incorporating special aggregates or waste materials. Major themes include microstructure, material properties, testing, durability, mechanics, modeling, design, fabrication, and practical applications. The journal welcomes papers on structural behavior, field studies, repair and maintenance, serviceability, and sustainability. It aims to enhance understanding, provide a platform for unconventional materials, promote low-cost energy-saving materials, and bridge the gap between materials science, engineering, and construction. Special issues on emerging topics are also published to encourage collaboration between materials scientists, engineers, designers, and fabricators.