干燥条件下混凝土非均匀收缩的测试方法  

MEASUREMENT METHOD FOR DIFFERENTIAL SHRINKAGE IN CONCRETE EXPOSED TO DRYING CONDITION

作　　者：高小建[1] 张爱莲[2] 

机构地区：[1]哈尔滨工业大学土木工程学院,哈尔滨150006 [2]四川建筑职业技术学院土木工程系,四川德阳618000

出　　处：《低温建筑技术》2010年第3期4-6,共3页Low Temperature Architecture Technology

基　　金：国家自然科学基金资助项目(50408016)

摘　　要：提出一种通过饱和盐溶液控制环境湿度、多组LVDT位移传感器为测试元件的混凝土收缩实验装置,可用于评价单面干燥条件下混凝土收缩变形分布特征。实测结果表明,距离干燥表面不同深度处混凝土存在明显的非均匀收缩变形,这种非均匀收缩会在混凝土表层部分形成自约束收缩应力,对混凝土收缩开裂产生加速作用;且这种非均匀收缩变形随着水灰比的减小而加剧。A new type of equipment for measuring concrete shrinkage was developed in this paper with saturated salt solution to control relative humidity of environment and several pairs of LVDT displacement sen- sors as measuring components. This equipment can be used to study shrinkage distribution characteristics of concrete with one surface exposed to drying condition. The test results show that shrinkage strain differs mark- edly in concrete according to the depth from drying surface. Such differential shrinkage may result in the for- marion of self-restraint shrinkage stress in the surface layer of concrete and consequently accelerate shrinkage cracking of concrete. And shrinkage difference in concrete exposed to drying condition increases with the de- creasing of water to cement ratio. Key words： drying condition; differential shrinkage; measurement method; water to cement ratio.

关 键 词：干燥条件 非均匀收缩 测试方法 水灰比 

分 类 号：TU528[建筑科学—建筑技术科学]