Predicting Damage in Single-Lap Composite Joints with Nonlinear CZM behaviour using FGM Concept in Fibre-Matrix Coupling Laws

Abstract

This work represents a novel and innovative numerical approach, which involves validating the results against experimental data to ensure reliability. This study focuses on incorporating the volume fraction of the FGM concept into the fibre-matrix mixing laws of unidirectional composites. Notably, a nonlinear formulation has been employed to account for the adhesive's ductility, and the CZM model has been integrated into the finite element analysis using the ABAQUS code. The CZM model in this study incorporates both shear and detachment modes, characterized by increasing adhesive stress in a trapezoidal shape. The proposed approaches introduce fibre presence in the matrix per layer, with concepts like C-1 having denser fibres in the middle of the thickness and others like C-2 and C-3 closer to the plate end. These concepts are designed to mitigate the transmission of loads to the adhesive joint and explore their influence on different responses and damage levels through adhesive plasticization. Additionally, due to the attached plates, the stiffness of the system significantly affects the overall response and resistance under mixed loading conditions.