A coupled ALE-Cohesive formulation for interfacial debonding propagation in sandwich structures

A numerical model to predict debonding phenomena in sandwich structures based on soft core and high performance external skins is proposed. In particular, the proposed model incorporates shear deformable beams to simulate the face sheet and a 2D elastic domain to model the core of the structure. Debonding processes is simulated by means a moving interface elements, introduced between the core and the face. The numerical interface strategy is consistent to a moving mesh technique based on Arbitrary Lagrangian–Eulerian (ALE), in which weak based moving connections are implemented by using the FE formulation. The moving mesh technique combined with a multilayer formulation ensures a reduction of the computational costs required to predict crack onset and subsequent evolution of the debonding phenomena. The accuracy of the proposed approach is verified by means comparisons with experimental and numerical results. Moreover, simulations in dynamic framework are developed to identify the influence of inertial effects produced by different typologies of core on debonding phenomena. The investigation revels the impact of mechanical properties of core on the dynamic debonding mechanisms.