Strain rate dependent failure criteria for fibrous composites using multiscale approach

Abstract

Recently, a set of failure criteria based on a multiscale model was developed for fibrous composites. Those criteria used stresses and strains occurring in the fiber and matrix material level. The failure criteria consisted of three failure modes such as fiber failure, matrix failure, and fiber/matrix interface failure. Those criteria were developed for quasi-static loading such that the effect of the strain rate was not under consideration. To model and predict failure of composite materials and structures subjected to dynamic loading, the effect of strain rate needs to be included in the failure criteria. The present work is to revise the former criteria to be applicable to the strain rate dependent composite materials, especially polymer composites. To validate the revised failure criteria, Charpy impact testing as well as quasi-static uniaxial testing were conducted. The test results agreed well with predicted failure loads using the new failure criteria.