Computer implementation of damage models by finite element and meshfree methods

摘要

A computational methodology of a micromechanics cell model is proposed to establish the constitutive law during material fracture. As an application example, the ductile fracture process has been investigated and a new model parameter function for damage is obtained based on a computational cell modeling technique. Aspects of computer implementation for finite element and meshfree methods are described. The technique is applied to numerical examples including necking behavior of a tensile bar, a cracked panel under tension, an edge notched panel under pure bending, a plane strain plate under compression, and the ductile tearing with large deformation of a notch-bend specimen. The applications of Reproducing Kernel Particle Method (RKPM) for the ductile fracture process involving damage evolution is studied and multiresolution analysis has also been performed on shear bands. The analytical and numerical results confirm that the proposed computational methodology provides an effective way to establish the relationship between macroscale and microscale mechanical behaviors, in conjunction with considering material heterogeneities such as damage at various scales. The numerical results also show that the multiple scale RKPM possesses a strong ability to capture the physical phenomena such as shear band, large deformation, and the material instability during damage evolution.