Chapter 8 - Viscoelastic bilinear cohesive model and parameter identification for failure analysis of adhesive composite joints using explicit finite element analysis

Abstract

This paper extends the bilinear cohesive model developed by Turon et al. (2006) [7] to the viscoelastic case by superimposing the additional integral-type cohesive tractions onto the regular tractions. The relaxation moduli in the viscous cohesive traction are further expanded by the Prony series. The finite-thickness middle-plane interface element technique is adopted to implement the regular bilinear cohesive model, and the viscoelastic cohesive traction is solved by the recursive algorithm. Then, an inverse method is presented to identify the Prony's series parameters by combining explicit FEA and experiments. Numerical analysis by ABAQUS-Python script language and MATLAB software is performed to explore the effects of cohesive strengths and load rates on the load responses for single-lap adhesive joints with brittle adhesive materials under low strain rate tension.