Stress singularity near the end of a cylindrical interface and the linear elasticity of push-in tests

Investigated is the push-in test used to determine the interfacial strength of fiber-reinforced composites via the method of singular integral equation. Singularity analysis shows that stresses near the end for an intact interface have a power singularity, and the singularity index is only dependent on the material constants of the fiber and the matrix. In order to describe the interfacial strength at the initial debonding of the push-in test, critical interfacial shear stress intensity factor and the related singularity index are adopted. This interfacial strength characteristic parameter is applied to analysis of the push-in test results of carbon fiber reinforced epoxy resin composites.