Simulation of composite delamination with Cohesive Zone Model

Finite element analysis using Cohesive Zone Method (CZM) is a commonly used method to investigate delamination in laminated composites. Accurate analysis of composite delamination using interface elements relies on having sufficient elements within a softening region known as the cohesive zone ahead of a crack tip. In this paper, simulation of composite delamination using interface elements is performed in Finite element code ANSYS. Contact elements were implemented for modeling cohesive layer. These 3-D elements have 4-Node and can be used for surface-to-surface contact with bi-linear form of the cohesive zone model. In addition, a closed-form expression is expressed to define the relationship between number of elements in cohesive zone and interfacial strength. Also length of the numerical cohesive zone has been investigated in detail and compared to closed-form solution