Stress distribution around holes in laminated composite plates

A solution is presented for the stress distribution around holes in laminated composite plates under pure bending. The shear deformation, lamination theory is derived and employed for the analysis of circular, elliptical, square, and diamond-shaped holes piercing the laminated composite plate. Each layer of the laminate is assumed to be homogeneous and to have isotropic properties. Functional analysis employing complex variable methods is used to solve the governing equations. Using conformal mapping and boundary form perturbation techniques, the circular hole solution has been extended to the solution of the curvilinear hole case.

These analytical solutions are compared with the solution obtained from a 72 DOF finite element method. The stress resultants and stress couples around the hole, the interlaminar stresses, as well as the tangential stress through the plate thickness are studied. In addition, the boundary layer phenomenon in the vicinity of the hole is presented.