Computational progressive failure of composite structures

Abstract

In this article, a novel element-failure method (EFM) is proposed for modeling the progressive failure of pin-loaded composite joints. The basic concept of EFM is that only the nodal forces are modified to reflect changes in the load-bearing capability of the damaged finite elements. Instead of the conventional contact algorithm, a more convenient method is provided using the EFM to solve the contact problem between the composite hole edge and pin surface. In conjunction with the Tsai-Wu (TW) failure theory and a more recent micromechanics-based strain invariant failure theory (SIFT), the EFM is used to predict damage initiation and propagation in composite laminates. Comparisons are also made with the more commonly used material property degradation method (MPDM). It has been shown that a good agreement between numerical predictions and experimental results can be obtained by SIFT-EFM for three typical failure modes of pin-loaded composite joints.