A METHOD FOR COSSERAT POINT ELEMENT (CPE) MODELING OF NONLINEAR ELASTIC MATERIALS

摘要

A method for Cosserat Point Element (CPE) modeling of nonlinear elastic materials, utilizing a strain energy function characterizing the response of an eight node 3-D brick element to homogeneous and inhomogeneous deformations, which includes full coupling of bending and torsional modes of deformation. The method includes determining the constitutive coefficients which satisfy bending and torsional modes of deformation for three specific reference element geometries and combining these solutions to obtain constitutive equations for general reference element shapes which ensure that the strain energy remains a positive definite function for all inhomogeneous deformations of the CPE. The constitutive coefficients characterize a generalized CPE model that predicts the response of a 3-D brick element for finite elastic deformations which is free of hourglass instabilities and locking for nearly incompressible materials, thereby providing a robust modeling tool.