INELASTIC DEFORMATION OF FIBER COMPOSITES CONTAINING BRIDGED CRACKS

An analysis of the inelastic tensile deformation of a fiber composite containing multiple bridged cracks of finite length is presented. Comp osite strains are predicted by using crack opening areas to account fo r the additional inelastic strain due to the cracks. The analysis is b ased upon a line-spring representation of the crack surface tractions associated with bridging fibers, accounting for frictional sliding alo ng the fiber-matrix interface with a constant shear stress. Approximat e analytical solutions are derived based on the assumption that the ne ar tip behavior of the crack dominates either the entire crack profile (for short cracks) or only a small portion of it (for long cracks). T hese results are compared to more detailed numerical solutions. The an alysis is extended to the case of cyclic loading, incorporating the hy steresis that occurs as a result of reverse slip along the interfaces. (C) 1997 Elsevier Science Ltd.