纳米SiO_2与水泥硬化浆体中Ca(OH)_2的反应  

INTERACTION OF NANO-SiO_2 WITH PORTLANDITE AT INTERFACE BETWEEN HARDENED CEMENT PASTE AND AGGREGATE

作　　者：叶青[1] 张泽南[2] 陈荣升[1] 马成畅[1] 

机构地区：[1]浙江工业大学建工学院,杭州310014 [2]浙江工业大学理学院,杭州310014

出　　处：《硅酸盐学报》2003年第5期517-522,共6页Journal of The Chinese Ceramic Society

基　　金：浙江工业大学科学研究中心资助项目

摘　　要：应用XRD物相分析和强度试验对纳米SiO2 与水泥硬化浆体中Ca(OH) 2 的反应进行了研究 ,从该体系中得到的纳米SiO2 为无定形的物质。纳米SiO2 与Ca(OH) 2 (晶体粉末 )的反应至少始于 1h龄期 ,而且在 3d龄期内反应速度较快 ;在掺质量分数为 3 %纳米SiO2 的条件下 ,纳米SiO2 能明显地降低在水泥硬化浆体和骨料界面中Ca(OH) 2 晶体的取向性 ,明显地减小界面Ca(OH ) 2 晶粒的尺寸 ,并能减少界面Ca(OH) 2 晶体的含量 ,特别是在早期就能改善界面。纳米SiO2 能明显地提高水泥硬化浆体的强度 。Interaction of nano-SiO2 with portlandite were studied by XRD, SEM/EDAX and the method for compressive strength of hardened paste as well. Results indicate that nano-SiO2 is an amorphous substance. The reaction between nano-SiO2 and portlandite starts from the first hour and the reaction velocity is quicker within 3 days. When 3% (in mass) nano-SiO2 is added to portlandite, the crystalline orientation degree, the crystalline size and the content of portlandite at the interface between hardened cement paste and aggregate are obviously decreased at early ages. The compressive strength is also increased at the same time. The aim of this research is to improve the interface structure and effectively to absorb portlandite formed at early ages by adding a small amount of nano-SiO2.

关 键 词：纳米氧化硅 氢氧化钙 相互作用 界面 水泥 

分 类 号：TU528[建筑科学—建筑技术科学]