Progressive Failure Analysis of an Open-Hole Composite Laminate by Using the S-Version Finite-Element Method

The application of the s-version finite-element method (SFEM) in the failure analysis of open-hole composite plates is illustrated by using the results of tension tests on a T700/epoxy laminate with a central hole. A modeling methodology for open-hole composite plates based on the SFEM is presented. Proper failure criteria and a material degradation rule are adopted in the progressive analysis. The Patran Comand Language (PCL) is employed for fast modeling and visualization. The FORTRAN scientific programming language and the PARDISO package for solving highly complicated and sparse equations are incorporated into the procedure for a high computational efficiency. Good agreement between experimental data and results of the conventional FEM for the failure and strength of the plates is obtained. Compared with the conventional FEM, the method proposed ensures an easy meshing technique in describing the stress concentration region around an open hole and requires less computer memory. The mesh-dependence and convergence of the approach are demonstrated by a parametric analysis.