A Novel Beam Model for Mode-II Delamination Analysis of Composite Laminates

A two dimensional beam model is proposed for delamination analysis of composite laminates, where Timoshenko's plane cross-section assumption is abandoned, and the longitudinal displacement of the beam is proposed as continuous functions of the transverse and the longitudinal coordinates, to match shear deformations. Moreover, the composite laminate is modeled as upper and lower sub-beam through the delamination interface, and corresponding conditions for interface sliding are satisfied through a generalized variational theory. The accuracy of the results of this analytical model is verified by comparison with those from three dimensional finite element models. Furthermore, the influences of delamination depth, length, central position and modulus mismatch ratio (E-1/E-2) of the upper and lower sublaminate to the energy release rate are discussed.