混凝土抗拉疲劳剩余强度损伤模型

基于连续体损伤力学理论,建立了各向异性混凝土抗拉疲劳剩余强度衰减模型.模型中采用了基于应变能量释放率空间的边界面模型,通过极限断裂面的不断移动模拟疲劳过程中损伤阈值的不断变化.提出了在高周疲劳过程中损伤模量表达式中的D为一与剩余强度有关的变量的观点,并给出了函数表达式.结合已完成的混凝土疲劳抗拉剩余强度试验,确定了模型的参数,并验证了模型的有效性.

Damage model for residual strength of concrete under tension fatigue loading

Based on the continuum damage mechanics,an anisotropic elasto-damage model for predicting the residual strength of concrete under tension fatigue loading is presented.The model utilizes the concept of multiple bounding surfaces,with a varying size limit fracture surface defining fatigue loading.D in the damage modulus expression is not a constant under high cycles.It is a variable which depends on the residual strength.The calculation parameters of the model are given according to the fatigue test results acquired. Comparison of the residual strength results indicates a good agreement between the theoretical model and the experimental data.