Nonlinear Dynamic Buckling Of Truncated Sandwich Shallow Shells

Nonlinear dynamic buckling of truncated sandwich shallow spherical shells and truncated sandwich shallow conical shells under multiform impact loads are investigated.In Chapter 1,a detailed investigation on impact buckling is summarized.The history and development in this field are introduced as well.The motion criterions which define the critical impact buckling are summarized according to the classification.Finally,the content and investigating methods in this dissertation are introduced.In Chapter 2,nonlinear dynamic buckling of sandwich shallow conical shells under uniform triangular pulse is investigated.Based on the Reissner's assumption,applying Hamiton's principle,the nonlinear dynamic governing equation of sandwich shallow spherical shells under uniform triangular pulse are built and solved by Galerkin method and Runge-Kutta method.Budiansky-Roth motion criterion expressed by the displacement of the rigid center of the shell is employed to determine the critical impact buckling load.The influences of physical parameter and geometric parameters on impact buckling are discussed as well.In Chapter 3,nonlinear dynamic buckling of s truncated sandwich shallow spherical shells under blast pulse is investigated.Galerkin method and Budiansky-Roth motion criterion are employed to determine critical impact buckling load.The influences of physical parameter,geometric parameters and boundary conditions on impact buckling are discussed as well.In Chapter 4,the whole paper is summarized some useful conclusions are obtained. Then,farther investigations about this problem are prospected.