Efficient Approximate Analytic Solution for the Problem of Stability of a Three-Layer Conic Shell Under Combined Loading

We propose a solution of the linear problem behavior an elastic three-layer conic shell under combined action several external force factors (uniform pressure, axial compression, and torque), which may lead to loss stability analyzed structure. The is reduced integration resolving singular sixth-order ordinary differential equation with variable coefficients. solutions obtained by methods phase integrals (WKB method), hybrid WKB–Galerkin method, finite-difference method are compared. demonstrate advantages asymptotic approach class equations. rational relationships between thicknesses elasticity moduli layers required for attainment highest investigated structure given loads analyzed. construction boundary surfaces separating regions instability discussed. efficiency shells as load-bearing elements aimed at improving confirmed.