混凝土轴拉疲劳试验及损伤模型

Fatigue tests and damage model of concrete under axial tension

基于室内试验,研究了混凝土在等幅和变幅重复荷载作用下的轴拉疲劳性能。由等幅疲劳残余应变,定义了损伤变量,得到了相应的损伤积累和演化规律。依据损伤演变与损伤状态、加载条件间的相关性,建立了相应的疲劳损伤模型。并用变幅疲劳试验结果验证了模型的有效性。与其它模型相比,该模型具有较高的精度。

The fatigue behavior of concrete under axial tension with constant and variable amplitude cyclic loading is investigated.The damage variable is defined as the residual strain of concrete under constant amplitude fatigue loading,and the law of cumulative damage and its evolution are obtained.According to the correlation between accumulative damage and loading level the fatigue damage model is established.The validity of the model is verified by the test results of variable amplitude loading.The accuracy of the model proposed is higher than other models.