Progressive failure analysis of composite materials based on rate-dependent three-dimensional elastoplastic damage model

A three-dimensional elastoplastic damage constitutive model which takes into account the nonlinear mechanical response, strain rate effects of composites, material properties degradation due to damage evolution was proposed. A modified plastic model was used to characterize the nonlinear mechanical response under dynamic load. To accurately describe the elastoplastic mechanical response of composite materials under dynamic load, the rate-dependent amplification factor was introduced to modify the plastic hardening law under static condition. In order to alleviate mesh sensitivity of finite element analysis results, the"Crack Band Theory"was applied to regularize the softening branch of the material constitutive model. The Selective Range Inverse Parabolic Interpolation algorithm was used to calculate the angle of the initial fracture plane of matrix damage and the angle of the fiber kinking/splitting plane. User-defined material subroutine VUMAT containing the numerical integration algorithm was coded and implemented in finite element procedure ABAQUS V6.14. The efficiency of the material constitutive model was demonstrated through progressive failure analysis of IM7/8552 carbon fiber/epoxy composite laminates, the mechanical behavior of which demonstrates significant nonlinear mechanical response. The numerical results agree well with the experimental data reported in the literature. It is shown that the rate-dependent three-dimensional elastoplastic damage constitutive model can predict the mechanical behavior of composites under dynamic loads with sufficient accuracy. The proposed approach provides an efficient method for the design of composite components and structures. Copyright ©2022 Acta Materiae Compositae Sinica. All rights reserved.