{"title":"镁偏高岭土胶凝材料:水化、性能及微观结构","authors":"Yongshan Tan , Xiangyi Cheng , Caijun Shi","doi":"10.1016/j.cemconcomp.2025.106256","DOIUrl":null,"url":null,"abstract":"<div><div>MgO-metakaolin (MK) systems is a novel magnesium-based cementitious material that is a potential candidate for the solidification and encapsulation of radioactive waste. This study investigates the effects of the MgO/MK mass ratio, water-to-binder ratio, and curing age on the hydration, properties and microstructure of MgO-MK cementitious materials. The results suggest that increasing the MgO/MK mass ratio caused an enhancement in the compressive strength and flowability of MgO-MK cementitious materials and significantly reduced the total heat release of the MgO-MK system. The main hydration products found in the microstructure of the MgO-MK systems are brucite, hydrotalcite, and magnesium (aluminum) silicate hydrate gel (M-(A-)S-H), with the amorphous M-(A-)S-H gel being the primary hydration product. The amount of hydration products increased with an increase in the MgO content. Further, a significant reduction in the porosity of the samples were observed with an increase in the MgO/MK mass ratio resulting in a dense microstructure.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"164 ","pages":"Article 106256"},"PeriodicalIF":10.8000,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"MgO-metakaolin cementitious materials: hydration, properties and microstructure\",\"authors\":\"Yongshan Tan , Xiangyi Cheng , Caijun Shi\",\"doi\":\"10.1016/j.cemconcomp.2025.106256\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>MgO-metakaolin (MK) systems is a novel magnesium-based cementitious material that is a potential candidate for the solidification and encapsulation of radioactive waste. This study investigates the effects of the MgO/MK mass ratio, water-to-binder ratio, and curing age on the hydration, properties and microstructure of MgO-MK cementitious materials. The results suggest that increasing the MgO/MK mass ratio caused an enhancement in the compressive strength and flowability of MgO-MK cementitious materials and significantly reduced the total heat release of the MgO-MK system. The main hydration products found in the microstructure of the MgO-MK systems are brucite, hydrotalcite, and magnesium (aluminum) silicate hydrate gel (M-(A-)S-H), with the amorphous M-(A-)S-H gel being the primary hydration product. The amount of hydration products increased with an increase in the MgO content. Further, a significant reduction in the porosity of the samples were observed with an increase in the MgO/MK mass ratio resulting in a dense microstructure.</div></div>\",\"PeriodicalId\":9865,\"journal\":{\"name\":\"Cement & concrete composites\",\"volume\":\"164 \",\"pages\":\"Article 106256\"},\"PeriodicalIF\":10.8000,\"publicationDate\":\"2025-07-24\",\"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/S0958946525003385\",\"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/S0958946525003385","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}
MgO-metakaolin cementitious materials: hydration, properties and microstructure
MgO-metakaolin (MK) systems is a novel magnesium-based cementitious material that is a potential candidate for the solidification and encapsulation of radioactive waste. This study investigates the effects of the MgO/MK mass ratio, water-to-binder ratio, and curing age on the hydration, properties and microstructure of MgO-MK cementitious materials. The results suggest that increasing the MgO/MK mass ratio caused an enhancement in the compressive strength and flowability of MgO-MK cementitious materials and significantly reduced the total heat release of the MgO-MK system. The main hydration products found in the microstructure of the MgO-MK systems are brucite, hydrotalcite, and magnesium (aluminum) silicate hydrate gel (M-(A-)S-H), with the amorphous M-(A-)S-H gel being the primary hydration product. The amount of hydration products increased with an increase in the MgO content. Further, a significant reduction in the porosity of the samples were observed with an increase in the MgO/MK mass ratio resulting in a dense microstructure.
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.