BUCKLING OF COMPOSITE ORTHOTROPIC CYLINDRICAL-SHELLS UNDER NONUNIFORM AXIAL LOADS

The static buckling of orthotropic composite cylindrical shells, under circumferentially non-uniform axial loads is investigated based on Flugge-type field equations. Use of a complex finite Fourier transform provides a simple method for handling any arbitrary non-uniform load but introduces modal coupling between the transformed equations. For simply supported boundaries (conditions SS3) the determination of the critical buckling load reduces to finding the eigenvalues of a finite matrix. Three different non-uniform loads are considered, having forms proportional to (1 + 2 cos theta), cos theta and H(theta* - theta) where H is the Heaviside function, theta is the circumferential coordinate and a theta* is the width of an axially loaded strip of the shell of radius a. Computed results indicate the sensitivity of the critical buckling loads to the type of non-uniform load and the material lay-ups of the cylinders.