Stress Analysis of Laminated Composites with Preformed Holes. Part 1. SinglePlies with Embedded Material Discontinuities

摘要

An Analytical and experimental study was conducted to develop a computationalmodel adequate for stress analyses of AS4/3501-6 composite plates containing preformed 1/4 diameter holes, which were found in previous and parallel experimental studies to possess superior open-hole tension and compression strengths relative to composites with drilled holes of equal diameter. The preformed-hole composites contain embedded material discontinuities resulting from the interpenetration of adjacent composite layers in the actual, laminated systems. The effort reported addresses the initial development of the model for single layers containing the material discontinuities present in laminates. The analytical method is suitable for adaptation to problems involving smart materials, electronic packaging, micro-electromechanical systems and joining/fastening. The proposed computational model is based on spline approximations of the displacement components. Solutions were obtained relative to curvilinear coordinates that mapped the preformed hole region onto a rectangular region and the embedded material boundaries into coordinate lines.... Composites, Holes, Embedded material, Variational method, Numerical analysis, Spline functions, Smart materials, Electronic packaging, MEMS, Joining, Fastening.