饱水轻集料内养护对高性能混凝土收缩的影响  

Effect of Internal Curing Caused by Saturated Lightweight Aggregate on Shrinkage of High Performance Concrete

作　　者：李北星[1] 查进[1] 李进辉[1] 高鹤[1] 崔巩[1] 周明凯[1] 

机构地区：[1]武汉理工大学材料科学与工程学院,武汉430070

出　　处：《武汉理工大学学报》2008年第5期24-27,共4页Journal of Wuhan University of Technology

摘　　要：混凝土内养护可以明显改善高性能混凝土自收缩,阐述了饱水轻集料内养护的作用机理,研究了饱水轻集料取代粗骨料对混凝土收缩的影响,试验结果表明:10%、30%、50%等体积取代粗骨料,有效降低混凝土自收缩和干缩,1d自收缩分别降低了12.5%、35%和65%,28 d自收缩分别降低了9%、29%和49%;混凝土干缩降低幅度随轻集料取代率的增加而增加,50%等体积取代时,1 d、3 d7、d1、4 d和28 d干缩分别降低了21%、26%、25%、26%和24%。Internal curing is especially beneficial to reduce autogenous shrinkage of high performance concrete. In this paper, the mechanisms of internal curing using saturated lightweight aggregate （SLWA） was described first. Then the effect of internal curing through partial replacement of coarse aggregates by SLWA on the development of shrinkage was investigated. Experimental results clearly demonstrated the efficiency of the substitution of coarse aggregate by SLWA in reducing autogenous shrinkage and drying shrinkage. When the coarse aggregate was replaced by SLWA at the percentage of 10%, 30% and 50% by volume, the autogenous shrinkage was decreased by 12.5%, 35% and 50% at age of 1 d, 9%, 29% and 49% at age of 28 d. The drying shrinkage drop increased with the increasing lightweight aggregate replacement. When the coarse aggregate was replaced by SLWA at the percentage of 50% by volume, the drying shrinkage was reduced by 21%, 26%, 25%, 26% and 24% at 1 d, 3 d, 7 d, 14 d and 28 d age respectively.

关 键 词：内养护 轻集料 高性能混凝土 自收缩 干缩 

分 类 号：U445[建筑科学—桥梁与隧道工程]