BUCKLING AND POSTBUCKLING BEHAVIOR OF CURVED COMPOSITE PANELS DUE TO THERMAL AND MECHANICAL LOADING

The buckling and postbuckling responses of unstiffened cylindrically c urved composite panels are studied using the finite element code STAGS and a geometrically nonlinear Rayleigh-Ritz solution. Loading is eith er through axial end-shortening at a fixed spatially uniform temperatu re, or it is temperature-induced due to the thermal stresses that aris e when the spatially uniform temperature is increased while axial end displacement is restrained to be zero. Comparisons are made between tw o sets of boundary conditions and three laminates. Buckling and postbu ckling responses are found to be strongly dependent on material orthot ropy and are substantially affected by the amount of circumferential r estraint along the straight edge boundaries.