5 - Experimental characterization of interlaminar shear strength

Abstract

Publisher Summary The stresses acting on the interface of two adjacent plies in composite laminates are called interlaminar stresses. Relative deformations between adjacent plies are caused by the stresses. If the stresses exceed the corresponding strength values that are constants for a particular composite material, failure along the interface takes place. Interlaminar stresses cause delamination failure. Delamination is the most critical failure mode in laminated composite materials. It can cause unstable crack growth in composite structures that leads to a catastrophic failure condition as a result of its influence on a component or structure made of laminated composite material in weakening its resistance to subsequent failure modes. The resistance to delamination of laminated composite material can be characterized using two different approaches, which are, the strength-of-materials approach and the linear elastic fracture mechanics approach. This chapter discusses the interlaminar shear strength of composite material, which is used in the strength-of-materials approach as the controlling factor for the initiation of delamination due to interlaminar shear.