轻集料与水泥石的界面结构  

INTERFACE STRUCTURE BETWEEN LIGHTWEIGHT AGGREGATE AND CEMENT PASTE

作　　者：胡曙光[1] 王发洲[1] 丁庆军[1] 

机构地区：[1]武汉理工大学

出　　处：《硅酸盐学报》2005年第6期713-717,共5页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(50272045);武汉理工大学硅酸盐材料工程中心教育部重点实验室开放课题基金(SYSJJ200410)资助项目。

摘　　要：采用扫描电镜、能量散射X射线能谱、背散射电子成像和显微硬度分析研究了高强页岩陶粒与水泥石的界面组成与结构。研究发现:高强页岩陶粒表层相对内部较为致密,轻集料与水泥石的界面呈嵌锁状,界面区宽度约为20～30μm,硅钙比、显微硬度均高于水泥石基体。粉煤灰等矿物外加剂能够起到优化轻集料与水泥石界面组成及结构的作用,在轻集料内水分的自养护和离子迁移作用下,矿物外加剂与氢氧化钙反应生成的水化硅酸钙凝胶颗粒填充和弥补轻集料的原始缺陷,进而提高轻集料的颗粒强度,并最终使轻集料混凝土的性能得到改善。The combination and structure of interface between lightweight aggregate and cement paste were studied by using scanning electron microscopy, energy dispersive X-ray analysis, back scattered electrons image and micro hardness analysis. The results show that the surface structure of the high strength lightweight aggregate is denser than its core. The lightweight aggregate interlocks with the cement paste boundary, 3.69 and the depth of the interfacial transition zone is about 20-30 μm. The ratio of silica to calcium and the micro hardness of lightweight aggregates are higher than that in cement matrix. With the addition of mineral the such as fly ash, the combination and structure of the interface are improved. Under the action of initial curing of water inside lightweight aggregate and ions diffusing between lightweight aggregate and cement matrix, the hydrated calcium silicate gels formed from the reaction of mineral additions and calcium hydroxide fill in the micro defects and cracks of lightweight aggregate. Therefore, the particle strength of lightweight aggregate and performance of concrete are eventually improved.

关 键 词：轻集料 界面 水泥石 矿物外加剂 

分 类 号：TU528.2[建筑科学—建筑技术科学]