A NEW DISPLACEMENT-TYPE STABILITY EQUATION AND GENERAL STABILITY ANALYSIS OF LAMINATED COMPOSITE CIRCULAR CONICAL SHELLS WITH TRIANGULAR GRID STIFFENERS

摘要

In this paper,based on the theory of Donnell-type shallow shell,a new displacement-type stability equations is first developed for laminated composite circular conical shellswith triangular grid stiffeners by using the variational calculus and generalized smeared-stiffener theory.The most general bending stretching couplings,the effect of eccentricity ofstiffeners are considered.Then,for general stability of composite triangular grid stiffenedconical shells without twist coupling terms,the approximate formulas are obtained forcritical external pressure by using Galerkin‘s procedure.Numerical examples for a certainC/E composite conical shells with inside triangular grid stiffeners are calculated and theresults are in good agreement with the experimental data.Finally,the influence of someparameters on critical external pressure is studied.The stability equations developed andthe formulas for critical external pressure obtained in this paper should be very useful in theastronautical engineering design.