Parametric responses of carbon-epoxy composite with delamination using cohesive gap element

Abstract

This paper focuses on the various parametric responses of the delaminated carbon-epoxy composite beam using a gap element. The analysis is based on the cohesive zone modelling approach, and it is implemented using the finite element software ANSYS APDL. In the study, a zero-thickness cohesive gap element that varies the cohesive stresses with the interfacial opening displacement along the localized fracture process zone is used. The available published results of the double cantilever beam test are used to validate the results obtained from the current analysis. The effects of fracture length, number of layers, angle of plies and thickness on delamination of a composite cantilever beam with edge pull is considered in this paper. The results show that the separation between the composite plies is proportional to the stiffness of the cohesive element, and an increase in the number of layers depicts a transition from anisotropy to orthotropy. Under mode I delamination, composite plies with 450 fibre angles exhibits increased torsional stiffness and global resistance. Also, a comparison between thin and thick laminates demonstrate that a laminate of 5 mm thick dissipates about 85% more energy than a composite laminate of 50 mm thick.