混凝土动态劈拉特性及损伤机理研究  

Dynamic Splitting Tensile Behavior and Damage Mechanism of Concrete

作　　者：宋来忠[1] 张伟朋[1] 周斌[1] 彭刚[2] 田为[2] 

机构地区：[1]三峡大学理学院,湖北宜昌443002 [2]三峡大学土木与建筑学院,湖北宜昌443002

出　　处：《三峡大学学报（自然科学版）》2015年第6期10-14,共5页Journal of China Three Gorges University：Natural Sciences

基　　金：国家自然科学基金资助项目(11171181;51279092)

摘　　要：利用大型多功能静动力三轴仪分别进行了干燥混凝土与饱和混凝土试件在不同应变速率下的动态劈拉试验.对混凝土的物理力学参数进行了统计分析,研究了加载速率、湿度对混凝土劈拉强度的影响.结果表明:干燥混凝土与饱和混凝土的劈拉强度随应变速率的增大而提高,饱和混凝土的劈拉强度对应变速率更为敏感;低应变速率下,饱和混凝土劈拉强度低于干燥混凝土的,而在高应变速率下饱和混凝土强度更高.建立了干燥混凝土与饱和混凝土在不同应变速率下的应力、时间曲线与同步声发射参数之间的对应关系,在此基础上对比分析了干燥混凝土与饱和混凝土劈拉损伤特性.The dynamic splitting tensile test of dry and saturated concrete specimens under five different loading rates were completed using a large multifunction static and dynamic force triaxial apparatus. Statistical analysis of physico-mechanical parameters of concrete is carried out. The influence of strain rate and humidity on the splitting tensile strength of concrete is researched. The results show that the splitting tensile strengths of dry and saturated concretes are proportional to the strain rate; the splitting tensile strength of saturated concrete is more sensitive to strain rate than dry concrete; the splitting tensile strength of saturated concrete is lower than dry concrete under low strain rate, but is higher than dry concrete under high strain rate. The corresponding relationship of dry and saturated concretes among stress, time and synchronous acoustic emission parameter under different strain rates are established. On this basis, the splitting tensile damage characteristics of dry and saturated concretes are analyzed and compared using acoustic emission technology.

关 键 词：混凝土 劈拉 动态性能 损伤 

分 类 号：TQ178[化学工程—硅酸盐工业]