循环荷载作用下饱和软黏土的损伤模型

A damage model for saturated soft clay under cyclic loading

基于各向同性弹塑性损伤和Prevost模型的基本理论,把弹塑性等向硬化、运动硬化和各向同性损伤结合起来,推导了循环荷载作用下不排水饱和软黏土的弹塑性动力损伤本构模型。由循环累积塑性偏应变建立损伤演化方程,以描述循环加载对软黏土结构的破坏作用,并通过对循环三轴试验的模拟验证了模型的有效性。结果表明,提出的模型能较好地描述饱和软黏土在循环荷载作用下的变形、孔压变化及模量损伤过程。

Based on the isotropic elastoplastic damage and Prevost model theory, a new dynamic elastoplastic damage model for saturated soft clay under undrained cyclic loading is presented. The new model combines isotropic hardening, kinematic hardening and isotropic damage. Then the damage evolution equation is established according to the accumulative plastic deviatoric strain to describe the destruction of the soft clay under cyclic loading. Finally, the validity of this model is confirmed by simulating cyclic triaxial test. It is shown that the new model can preferably depict the deformation, pore pressure variation and modulus damage of the saturated soft clay subjected to the cyclic loading.