自密实混凝土自生约束收缩开裂性能试验研究.pdf

文档介绍：学兔兔
第 13卷第 5期建筑材料学报 。
2010年 1O月 joURNALOF BUILDING MATERIALS O ct.,2O10
文章编号:1007—9629(2010)05—0607—06
自密实混凝土自生约束收缩开裂性能试验研究
郑建岚, 王国杰, 王辉明
(福州大学土木工程学院,福建福州 350002)
摘要:通过钢环内壁贴应变片的环形约束收缩试验,研究了自密实混凝土由自生收缩引起的受力
、矿渣单掺和复掺为主要因素,研究了自生约束收缩下自密实混
凝土试件的钢环应变随龄期的发展规律,分析了钢环应变、混凝土有效自生收缩应变、混凝土收缩
应力、:单单自生收缩足以导致自密实混凝土环开裂,粉煤灰
等量替代水泥能有效降低由自生约束收缩引起的混凝土应力,但掺量过高时混凝土的抗拉强度会
明显下降;矿渣等量替代水泥或粉煤灰使混凝土的自生收缩应力增大,抗拉强度略有增加;混凝土
环开裂时试件开裂风险系数为 ~,掺和料对开裂风险系数有影响.
关键词:自密实混凝土;约束收缩;自生收缩;环形试验;开裂;矿物掺和料
中图分类号: 文献标志码:A doi:.1007—
Experimental Study on Cracking Tendency under Restrained
Autogenous Shrinkage pacting Concrete
ZHENGJian—lan, W ANG Guo—jie, WAN G Hui—ruing
(School of C Engineering,ivil F uzhou University,Fuzhou 350002,China)
Abstract:Autogenous shrinkage of pacting concrete(SCC) was studied by restrained ring test.
Taking flyash and granulated blast—furnace slag(GBS)content as main parameters,development of steel
ring strains as function of concrete age was investigated;correlations between steel ring strains,effective
autogenous shrinkage,tensile stress and cracking risk coefficient(CRC)of SCC specimens were studied.
The results show that the autogenous shrinkage alone can cause crackingof concrete ash is
helpful to decrease the tensile stress induced