Design of Laminated Composite Plates Containing a Hole under In-Plane Loadings

In this work, the design of a symmetric laminated composite plate with a circular opening subject to in-plane loading is considered. Stresses are calculated using Lekhnitskii’s complex variable approach with finite width correction. To take care of the variation of stresses around the hole, Tsai-Wu quadratic failure criterion is modified with a characteristic length defined in terms of the hole size and the laminate configuration; as a result, a procedure like point stress criterion developed by Whitney and Nuismer is followed. Comparisons of strength predictions and experimental data for certain layup are presented to see the validity of the failure model developed. Optimum laminate configuration is obtained by considering the maximum first ply failure strength. An effective, quick and easy method is provided.