Abstract:

This paper deals with the nonlinear dynamic buckling of functionally graded cylindrical shells under axial and lateral step loads. In the investigation, a nonlinear dynamic equilibrium equation is deduced using an energy method and is then solved by means of the four-order Rugge-Kutta method with various step lengths. Thus, the response curves of the shell structure are derived, which are combined with the B-R dynamic buckling criterion to determine the critical buckling condition. Numerical results show that （ 1 ） there is a dominating mode of structural deformation under step loads, which aroused the earliest structural response with maximum amplitude; （2） in the case of axial and lateral step loads, the nonlinear dynamic buckling loads are quite close to the corresponding linear static ones; （3） under axial step loads, the dynamic load would inspire a buckling mode with higher order; （4） the dynamic buckling load of the structure increases with the content of ceramic constituent ; and （5） the critical load in the linearly-distributed temperature field is close to that in the actual thermal-conduction temperature field.

Key words: functionally graded material, cylindrical shell, dynamic buckling, nonlinearity, B-R criterion