FORMULATION OF AN IMPROVED SMEARED STIFFENER THEORY FOR BUCKLING ANALYSIS OF GRID-STIFFENED COMPOSITE PANELS

An improved smeared stiffener theory for stiffened panels is presented that includes skin-stiffener interaction effects. The neutral surface profile of the skin-stiffener combination is developed analytically u sing the minimum potential energy principle and statics conditions. Th e skin-stiffener interaction is accounted for by computing the bending and coupling stiffness due to the stiffener and the skin in the skin- stiffener region about a shift in the neutral axis at the stiffener. B uckling load results for axially stiffened, orthogrid, and general gri d-stiffened panels are obtained using the smeared stiffness combined w ith a Rayleigh-Ritz method and are compared with results from detailed finite element analyses. Copyright (C) 1996 Elsevier Science Limited