以不同形态硅灰配制的高强混凝土的力学性能  

Mechanical Properties of High Strength Concrete Prepared with Different Densities of Silica Fume

作　　者：阎培渝[1] 张波[1] 

机构地区：[1]清华大学土木工程系,教育部土木工程安全与耐久重点实验室,北京100084

出　　处：《硅酸盐学报》2016年第2期196-201,共6页Journal of The Chinese Ceramic Society

基　　金：教育部博士点基金项目(20130002110033);国家自然科学基金项目(51278277)

摘　　要：研究了水胶比为0．24或0．29、硅灰掺量为0～10％、养护温度为20℃或50℃时，掺加加密硅灰或原状硅灰所配制的高强混凝土的力学性能发展。结果表明：加密硅灰与原状硅灰在混凝土制备过程中都能均匀分散于胶凝材料浆体中，起到增强作用，有利于促进混凝土强度发展。硅灰的增强效果在水化7d以内不明显，混凝土的强度增幅小于5％。原状硅灰的增强效果稍高于加密硅灰。在不超过胶凝材料总量10％的范围内提高硅灰的掺量对混凝土的增强效果更明显。提高养护温度可促使硅灰的增强作用提前发挥，使混凝土获得较高的早期强度，7d时混凝土的强度增幅大于10％，但28d后强度持续发展的幅度减小，导致湿热养护的混凝土的长期强度低于常温养护的混凝土。The mechanical properties of high strength concrete prepared with different bulk densities of silica fume at water binder ratio of 0.24 or 0.29, silica fume dosage between 0-10% and curing temperature of 20 ℃ or 50 ℃ were investigated. The original and densified silica fume both can be dispersed uniformly into the binder paste during the preparation process Of concrete to enhance the strength development of concrete. The strengthening effect of silica fume is not significant before 7 d. Its increasing range is less than 5%. The strengthening effect of original silica fume is a little better than that of densified silica fume. The increase of silica fume dosage in a range of ≤10% binder content can increase its strengthening effect. Elevated curing temperature can prompt the strengthening effect of silica fume earlier. The increasing range of strength for the concrete containing silica fume at 7 d duration is higher than 10% comparing with the concrete without silica fume, but the increasing rate slows down after 28 d duration. Therefore, the later strength Of concrete cured at elevated temperature is lower than that cured at room temperature.

关 键 词：加密硅灰 原状硅灰 高强混凝土 养护温度 强度 

分 类 号：TU528[建筑科学—建筑技术科学]