Micromechanical analysis of fiber fracture in unidirectional composite materials

In this paper, the problem of a penny-shaped crack in the center of multiple concentric cylinders is considered. By making appropriate choices for the stress functions in each of the constituents and making the standard assumptions of linear elasticity, it is possible to reduce the problem to the solution of a Fredholm integral equation of the second I:ind which may be solved numerically. This solutionis used in conjunction with a geometry approximation to model the stress concentrations due to a broken fiber in a unidirectional composite material. The results suggest that models of such a shear lag may be missing important features of the stress state including surrounding broken fibers in composite materials. Copyright (C) 1996 Elsevier Science Ltd.