Dynamic behavior of delamination and transverse cracks in fiber reinforced laminated composites

In this paper a numerical method is developed to study the dynamic behavior of delamination and transverse cracks in lamianted fiber-reinforced composite plates of finite dimension. The plate is subjected to time dependent antiplane shear stress field which is acting on the plate surfaces. The interaction of waves diffracted at the crack tip with those reflected at the plate boundaries and transmitted at the material interface makes the problem very complicated, so analytical study of this problem cannot be carried out with our present state of knowledge. Hence the problem is solved numerically. A versatile functional is developed which can handle delamination and transverse cracks with any orientation in multilayered composite laminates. The variational principle is adopted in frequency domain to obtain the finite element equations. The numerical difficulty associated with the singular behavior of the stress field near the crack tip has been avoided by using quarter point elements.