Finite element prediction of the post-impact compressive strength of fibre composites

Abstract

Low-velocity impact damage to composite laminates results in a complicated pattern of fibre cracks, matrix cracks and delaminations. The complexity of the damage has made the prediction of compressive strength reduction difficult since the mechanisms of failure are difficult to discern. In this paper a finite element prediction of post-impact compressive strength is described based on a stress analysis of a laminate containing buckled delaminated plies. The strength reduction mechanisms have been assessed from tests on laminates containing artificial simplified damage similar to real impact damage. Excellent agreement between experimental failure loads and finite element predictions has been found.