Micromechanics-based progressive failure analysis of carbon fiber/epoxy composite vessel under combined internal pressure and thermomechanical loading

A progressive failure analysis algorithm based on micromechanics of failure (MMF) theory and material property degradation method (MPDM) is developed, wherein the MMF is used to predict the failure initiation at constituent level and the MPDM is employed to account for the post failure behavior of the damaged materials. The progress of damage is controlled by a linear damage evolution law, which is based on the fracture energy dissipating during the process. This micromechanics-based approach is implemented by a user-material subroutine (UMAT) in ABAQUS, which is sufficiently general to predict the ultimate strength and complex failure behaviors of the composite vessel subject to both high pressure and thermal loading. In addition, the predictions of the model are also compared with those by experiment and traditional finite element analysis.