密实度对水泥基材料收缩开裂性能的影响  

Effect of Compactness on Shrinkage Cracking of Cement-Based Materials

作　　者：马一平[1] 刘静静[1] 朱蓓蓉[1] 杨晓杰[1] 

机构地区：[1]同济大学先进土木工程材料教育部重点实验室,上海201804

出　　处：《建筑材料学报》2014年第1期126-131,共6页Journal of Building Materials

基　　金：国家重点基础研究发展计划(973计划)项目(2009CB623104-5);国家自然科学基金资助项目(51308406);中央高校基本科研业务费专项资金资助项目(0500219143)

摘　　要：定义了一种塑性浆体湿密实度的测定方法,建立了一种新型快速干燥收缩法.将试件分别放入不同温度的烘箱,研究不同干燥时间内水泥基材料的干燥收缩率的变化.新型快速干燥收缩法与常温法结果相似,能明显缩短干燥周期.试验以普通硅酸盐水泥为胶凝材料制备了不同密实度的水泥基材料,探讨水泥基材料的密实度对其收缩开裂性能的影响.结果表明:密实度的下降可抑制水泥基材料的塑性收缩开裂程度,增大其干燥收缩率,但对硬化早期收缩开裂程度影响不大.An experimental method of wet compactness for plastic slurry was designed, and a new method of rapid drying shrinkage was set up for studying the change of drying shrinkage for hardened cement-based materials in ovens of different temperature at different drying time. The results of this new rapid drying shrinkage method correspond to that under normal temperature, which can obviously shorten the drying cy- cle. The cement-based materials having different compactness were prepared by using Portland cement as binder. And the effect of the compactness of cement-based materials on its shrinkage cracking was investi- gated. The results show that with the decrease of the compactness of the cement-based materials, the de- gree of plastic shrinkage can be restrained, and the drying shrinkage rate can be increased, whereas the effect on the degree of early drying shrinkage cracking of hardened cement-based materials can be ignored.

关 键 词：水泥基材料 湿密实度 塑性收缩开裂 硬化干缩开裂 

分 类 号：TU525[建筑科学—建筑技术科学]