Abstract
An interface element, taking account of both the material strengths and the fracture characteristics, is proposed to numerically simulate the damage propagation process in composite laminates. Several refinements are examined for the element to ensure the smooth convergence of the solution during the calculation of the damage when incorporated in the commercially available finite element package program (MARC) through user subroutine. The element has been successfully applied to a fundamental problem of the stable crack propagation and the crack initiation. Propagation process of multiple interlaminar delaminations in circular axi-symmetric nonlinear plates subjected to a quasi-static transverse load has been solved to demonstrate the applicability and efficiency of the present element to a complex delamination propagation problem. As continuous stress distribution with respect to the surface separation along the crack path are assumed on the interface, smooth and stable convergence of the solution of the crack propagation can be realized with fairly coarse mesh compared to the modeling where discrete interface traction force is assumed only at the nodes on the interface. Since the element would be taking into account the dissipated energy during the formation of crack surface, it can be applied to the simulation of dynamic failure process.
