在边界面塑性理论的基础上,提出了一个可以描述循环荷载作用下结构性饱和软黏土力学特性的各向异性弹塑性模型。通过在本构方程中引入表征土体结构性损伤内变量的方法,将软黏土结构损伤与累积塑性应变的发展联系起来;并引入各向异性张量及旋转硬化法则描述其各向异性及演化特征。同时,在映射准则的定义中采用映射中心可移动的方法,以反映土体在卸载再加载时的弹塑性。通过对典型结构性软黏土及上海软黏土循环三轴试验结果的模拟,初步验证了模型的合理性和有效性。
On the basis of a plastic bounding surface model,an anisotropic elasto-plastic model for saturated structured soft clay under cyclic loading is proposed.The effect of damage on structure caused by accumulated plastic strain is modeled with inner variable introduced into the corresponding equations,linking the structure damage with accumulated plastic strain increments.An anisotropic tensor and the rotational hardening law are introduced to reflect the evolution of anisotropy.Besides,by adopting the method of mobile mapping origin,the mapping rule is modified to simulate the elasto-plastic property of soils under cyclic loading.The validity of the model is verified by the cyclic test data of typical structured clay and Shanghai clay.