土体的椭圆──抛物双屈服面模型及其柔度矩阵

The elliptic-parabolic yield surfaces model and its softness matrix

本文证明了以经典塑性理论为基础的弹塑性模型的土体应力－应变柔度矩阵不能满足主对角线元素应占优的要求．为此作者提出了修正的椭圆──抛物双屈服面模型．

The clements on leading diagonal line of stress-strain scftness matrix should be dominant. However,it is proved in this paper that the plastic softness matrix of the models on the basis of classical plastisity theory does not satisfy the requirement. Then the elastic-plastic softness matrix, which is the sum of plastic and elastic softness matrixes, may not satisfy the requirement in some stress state. All models of such kind, including Cam clay model and the elliptic-parabolic yield surface model, have this problem. In this paper a modified elliptic = parabolic model with two yield surface is developed to overcome the shortcoming.