DESIGN TOOL FOR LAMINATED COMPOSITE STRUCTURES DISBOND ARREST MECHANISM

摘要

An analytical model for analyzing the effectiveness of a fastener as a crack arrest mechanism has been developed. The effect of the fastener in the through-thickness direction (Mode I) and sliding direction (Mode II) is modeled by springs using fastener flexibility approach. It is shown that the fastener provides significant crack retardation capability in any general loading. A FEA model for the problem is developed. The FEA results provide insights into the problem of disbond and delamination arrest using a fastener or similar mechanisms. The model of interest consists of a symmetric split beam with the free ends attached with a fastener. The mode decomposed strain energy release rates at the crack tip are evaluated analytically. The primary goal of the current work is to enhance the safety and efficiency of bonded composite structures by providing analysis methods for crack arrest mechanisms.