Theoretical Study of the Fracture in Three-layered Composites Obeying Non-linear Stress-Strain Relations

摘要

The present study concerns with the non-linear fracture in three-layered polymer composite beam subjected to tension. The inner layer is made by composite material for which unlimited validity of the Hook's law is supposed. The mechanical behaviour of the composite building the outer layers is modeled using three different non-linear stress-strain diagrams. It is assumed that the beam contains two inter-laminar cracks between the layers. Closed form analytical solutions of path independent J-integral are derived for characteristic magnitudes of external force corresponding to typical values of the stresses and strains in the beam layers. For this purpose, a non-linear model based on Mechanics of materials is used. The solutions obtained are expressed in a function of the external force magnitude and geometrical and physical properties of the layers. This paper contributes towards developing methods for non-linear analysis of inter-laminar fracture in three-layered composite beams.