An improved peridynamic model for failure analysis of composite laminates

The study presents an improved peridynamic (PD) model for predicting the failure mode of composite laminates without any limitation to fiber orientation. In order to describe the directional dependency of composite laminae, the structural rotation angle is introduced into the PD framework to overcome the flaw that the fiber orientation is a specific value in conventional PD models. In improved PD model (IPM), two types of material points are used to model laminated structures, and a new force function mapping relationship is derived to achieve stable load transfer between in-plane and interlayer material points. As a result, the discrete grid of in-plane material points do not have to coincide with interlayer material points, and the technical difficulties in modeling multilayer laminates with general layups can be addressed. Since the IPM matches the microscopic configuration of practical composite structures, these damage characteristics, such as the damage path, crack initiation point, etc., correlate well with the experimental results. The numerical accuracy of the developed PD model are verified by simulating a series of examples of composite laminae with different fiber orientations, and the damage example further demonstrates the strong capability of the IPM in capturing failure modes of laminates with general layup.