High-fidelity prediction of low-velocity impact damage in straight and variable angle fibre laminates with a semi-discrete continuum damage mechanics approach

Abstract

Accurate and efficient finite element modelling of Low-Velocity Impact (LVI) damage in laminated composites remains highly sought, due to the poor detectability and quantifiability of this damage by physical means. In this work, a novel semi-discrete continuum damage model is applied to simulate LVI-induced damage in multidirectional laminates within a ply-by-ply modelling framework. Contrary to the standard practice that requires fibre-aligned individual ply meshes held together by kinematic constraints at mismatched mesh interfaces, the present mesh orientation-independent crack model is able to use a uniform mesh pattern for the entire laminate, reducing the meshing burden substantially. Additionally, the computational time gets reduced due to the elimination of kinematic constraints from the system of equations. Three challenging examples are presented involving LVI on a cross-ply, multidirectional straight fibre and a variable angle tow (VAT) fibre laminate, showing the method’s general applicability. In all cases, the overall laminate behaviour upon impact, the network of complex cracks, including the curvilinear crack profile development in a VAT laminate, and the intricate crack-delamination interaction as seen in experiments, are reproduced with high fidelity.