NONLINEAR-THEORY FOR COMPOSITE LAMINATED SHELLS WITH INTERFACIAL DAMAGE

Interfacial damage is incorporated in the proposed nonlinear theory fo r composite laminated shells. A spring-layer model is employed to char acterize damaged interfaces spanning from perfect bonding to different degrees of imperfect bonding in shear. By enforcing compatibility con ditions for transverse shear stresses both at interfaces and on two bo unding surfaces of a laminated shell, only five unknown are needed for modeling its behavior. The principle of virtual work is used to deriv e the governing equations, which are of 14th order in lines of curvatu re coordinates, variationally self-consistent with seven prescribed bo undary conditions. This theory includes the conventional higher-order zigzag model for a perfectly bonded shell as a special case. Numerical results provide a physical understanding of the effect of interfacial damage on bending and buckling responses of composite laminated shell s.