Effect of Fiber Waviness on Buckling Strength of Composite Plates

Abstract

This paper explores the idea of tailoring the profile of reinforcing fibers to improve the buckling strength of composite plates. This paper analyzes the uniaxial buckling behavior of composite laminates in which fibers are placed along parallel sinusoidal curves, instead of the conventional straight line pattern. The sinusoidal fiber orientation results in variable elastic stiffness and nonuniform prebuckling stress fields, which are shown to have a pronounced influence on the buckling strength. For example, changing the fiber orientation from straight line to a sinusoidal pattern can increase the buckling load of a simply supported laminate by more than 80%. For the analysis, a computerized Rayleigh-Ritz procedure is developed that exploits an analogy between bending and stretching formulations to model a variety of boundary conditions.