Simulation of inelastic response of multidirectional laminates based on stress failure criteria

Abstract

The primary purpose of this paper is to simulate the non-linear stress–strain curve of a multidirectional laminate subjected to an arbitrary in plane load using constituent material data and laminate geometrical parameters. The simulation is performed at a ply level. The classical laminated plate theory is employed to determine the load shared by each lamina in the laminate, while internal stresses in the constituent fibre and matrix of the lamina are obtained using a recently developed bridging micromechanics model. Thus, various failure criteria can be incorporated to detect the failure of a lamina in the laminate, and a progressive failure process is assumed by stiffness discount. Another objective of this paper is to investigate the influence of three typical failure criteria, i.e. the maximum normal stress criterion, the Tsai–Wu criterion, and the Hashin–Rotem criterion, on the simulation. Prediction has been made for T300/5208 graphite–epoxy laminates of a number of layups subjected to uniaxial tension. For the considered laminates, the predicted curves agree well with available experimental data. It is found that the predic tions based on the maximum normal stress criterion are comparable with those based on the other two criteria. As the maximum normal stress criterion is the simplest in application, it is recommended as the first candidate for laminate non-linear and failure analysis.