核壳结构磷石膏基骨料/硅酸盐水泥界面特性及其调控  

Interface Characteristics and Regulation of Core-Shell Structure Phosphogypsum-Based Aggregate/Portland Cement

作　　者：何静 吕伟 吴赤球 余正康 李义胜 水中和[1,3] HE Jing;LYU Wei;WU Chiqiu;YU Zhengkang;LI Yisheng;SHUI Zhonghe(School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China;Hubei Changyao New Materials Co.,Ltd.,Yichang 443000,China;State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]武汉理工大学材料科学与工程学院,武汉430070 [2]湖北昌耀新材料股份有限公司,宜昌443000 [3]武汉理工大学硅酸盐建筑材料国家重点实验室,武汉430070

出　　处：《硅酸盐通报》2025年第2期613-622,共10页Bulletin of the Chinese Ceramic Society

摘　　要：为解决磷石膏基骨料与普通硅酸盐水泥的相容性问题,本文制备了一种核壳结构磷石膏基骨料。在系统研究骨料壳层组分对骨料吸水率、筒压强度及抗压强度等宏观性能影响的基础上,借助现代分析测试方法研究了骨料壳层组分对混凝土界面过渡区微观结构特性的影响。结果表明,核壳结构磷石膏基骨料的性能较未包壳层骨料均得到提升,并且该骨料与普通硅酸盐水泥制成的混凝土试块抗压强度得到提升。核壳结构磷石膏基骨料和水泥形成的界面与未包壳层的相比,在水化早期,降低了界面处Ca(OH)_(2)的含量,优化了界面处的孔隙结构,提高了界面处显微硬度,降低了界面过渡区宽度,并且该壳层可降低骨料内核S元素向界面处扩散的概率;在水化后期,界面处水化反应基本稳定,该壳层仍可减缓内核S元素向界面扩散的趋势,降低了界面处膨胀和开裂的风险,增加了磷石膏基骨料在普通硅酸盐水泥体系中应用的可行性。In order to solve the compatibility problem between phosphogypsum-based aggregate and ordinary Portland cement,a core-shell structure phosphogypsum-based aggregate was prepared in this paper.Based on the systematic study of the influence of the composition of aggregate shell on the macroscopic properties such as aggregate water absorption,cylinder compressive strength and compressive strength,the influence of the composition of aggregate shell on the microstructure characteristics of the interfacial transition zone of concrete was studied by means of modern analysis and testing methods.The results show that the performance of the core-shell structure phosphogypsum-based aggregate is improved compared with the uncoated aggregate,and the compressive strength of the concrete test block made of this aggregate and ordinary Portland cement is improved.The interface formed by phosphogypsum-based aggregate and cement with core-shell structure is compared with that without shell.In the early stage of hydration,the content of Ca(OH)_(2)at the interface is reduced,the pore structure at the interface is optimized,the microhardness at the interface is improved,the width of the interfacial transition zone is reduced,and the shell layer can reduce the probability of S element in the aggregate core diffusing to the interface.In the later stage of hydration,the hydration reaction at the interface is basically stable,and the shell layer can still slow down the trend of S element diffusion from the core to the interface,reduce the risk of expansion and cracking at the interface,and increase the feasibility of the application of phosphogypsum-based aggregate in ordinary Portland cement system.

关 键 词：磷石膏基骨料 核壳结构 界面过渡区 反应机理 孔隙率 

分 类 号：TU526[建筑科学—建筑技术科学]