UH模型切线刚度矩阵对称化及其应用

SYMMETRIZATION AND APPLICATIONS OF TANGENT STIFFNESS MATRIX FOR UH MODEL

分析了目前常用的几种土的本构模型三维化方法以及变换应力方法的优势.详细分析了用变换应力三维化本构模型非关联流动的本质,针对因采用非关联流动法则而带来的本构模型切线刚度矩阵的非对称性,建立了本构模型切线刚度矩阵的对称化方法.将此方法应用于UH模型并进行了有限元分析,进行了三轴伸长试验有限元分析.通过以上分析比较发现,切线刚度矩阵对称化方法能够明显改善有限元分析的收敛性,缩短分析时间,有着非常好的应用前景.

Several common three-dimensional generalized methods for constitutive models and the superiority of the transformed stress （TS） method are analyzed in this paper. The non-associated flow of constitutive model based on the TS method is analyzed in detail. The symmetrization method of tangential stiffness matrix for the constitutive models is proposed. The essence of the constitutive models with non-associated flow of tangential stiffness matrix is the same as original one using the symmetrization method. The finite element analysis to some triaxial extension tests is carried out. Based on the analysis and the comparison, it is found that the symmetrization method of tangential stiffness matrix can improve the convergence of finite element analysis and reduce simulation time obviously.