Dynamics of Three-Layer Inhomogeneous Cylindrical Shells on Elastic Foundation Under Nonstationary Loadings.

The dynamics of three-layer cylindrical elements with an inhomogeneous filler rested on the Winkler elastic foundation under various boundary conditions is studied. The distances between ribs in the light filler are much larger than the dimensions of the ribs cross-sections. Because of this, the theory of independent static and kinematic hypotheses is applied to each layer. In accordance with the Hamilton-Ostrogradsky variational principle the motion equations of the three-layer cylindrical shells rested on the Winkler elastic foundation and natural boundary conditions are obtained using the models of Timoshenko's shell and rod theory. This made it possible to produce an adequate finite-element model for three-layer cylindrical shells of different materials and obtained numerical results of the nature of dynamic behavior of a three-layer structure on an elastic foundation by employing the finite element method. The influence of the physical-mechanical parameters of layers of cylindrical structures on natural frequencies, methods of fastening their ends, parameter of shells elastic foundation on their dynamics under axisymmetric internal impulsive loading is investigated. New mechanical effects are revealed. [ABSTRACT FROM AUTHOR]