A segment-to-segment cohesive contact network approach for mesoscale composites failure modelling

Abstract

This paper presents an efficient and novel cohesive contact network approach, modelling multiple mesoscale composite failures including delamination, matrix cracking, and fibre rupture within large assemblies, such as the tow-wise assembled automated fibre placement or filament wound composites. The various failure modes are modelled by allocating cohesive contact interfaces with different input parameters along or perpendicular to the fibre axis, forming an interconnected cohesive contact network. The strict element size requirement of damage modelling in traditional methods is significantly alleviated with the use of an advanced segment-to-segment contact formulation. This method allows for greater mesh sizes at the crack front (comparable to the cohesive zone length) which opens up the possibility of modelling multiple potential failures at the sub-component or even structural level with current computational resources. Several numerical studies including double cantilever beam, end notched flexure, fixed ratio mixed mode, and quasi-isotropic laminate tension are carried out to demonstrate the feasibility and efficiency of the proposed approach. The matrix cracking and delamination, as well as their interactions, which ultimately lead to fibre rupture are properly captured. The global response and final damage pattern also show an excellent agreement with the published numerical and experimental results.