Three-Dimensional extended Kantorovich solution for accurate prediction of interlaminar stresses in composite laminated panels with interfacial imperfections

Abstract

An accurate three-dimensional (3D) elasticity solution is presented for static analysis of flat laminated panels with interlaminar bonding imperfection under arbitrary boundary conditions exhibiting edge effects. The recently developed mixed-field multiterm extended Kantorovich method (MMEKM) for 3D solution of perfectly bonded laminates is generalized to include the interfacial compliance characterized by displacement jumps. A general variationally consistent framework using the Reissner-type mixed variational principle is proposed to treat the imperfect interfacial conditions. It is shown through numerical studies on composite and soft-core sandwich panels under different boundary conditions that, similar to the perfect bonding case, the MMEKM yields accurate results with just two or three terms and in two or three iterations for the weakly bonded laminates also. The roles that the boundary conditions, locations of the imperfect interfaces, and span-to-thickness ratios play on the effect of weak bonding on the response of laminated structures are investigated for a wide range of values for the imperfection compliance.