Modeling Strength of Multidirectional Laminates under Thermo-Mechanical Loads

Abstract

This paper investigates the progressive failure process in a multidirectional composite laminate subjected to an arbitrary thermo-mechanical load condition. A micromechanics modeling approach is employed to predict each-ply failure strength of the laminate and to identify the corresponding failure mode. The analysis has incorporated both material non-linearity and stiffness reduction. The load shared by each lamina in the laminate is determined based on the classical laminate theory, whereas the internal stresses in the constituent fibers and matrix of the lamina are explicitly related to this load by making use of combining the bridging model and the Benveniste and Dvorak’s formula. The lamina failure is assumed whenever any constituent material attains its ultimate stress state. A generalized maximum normal stress criterion is employed to detect the constituent failure. In this approach, all the simulation equations are given explicitly, no iteration is involved, and a minimum number of input data are required. Comparison of the predicted thermo-mechanical strengths of several laminates with available experimental data is favorable.