Dynamic Stability Analysis of Shell-like Lattice Structures subjected to Follower Forces with Small Disturbances

Abstract

The deformation mechanisms of submerged shell-like lattice structures with membrane are in principle of a non-conservative nature because the working load is the follower type as hydrostatic pressure. Dynamic behaviors of arch-lattice framework subjected to follower forces are governed by several geometric and physical factors like curvatures, boundary conditions, loading, disturbances, contributing to the overall possibility of a dynamic failure at interval of its deformation history. Also, disturbance forces, exiting in a marine environment, lead the structure to exhibit dynamic instabilities at a much earlier stage than that could be predicted by a static stability criterion.This paper presents the governing equations for the finite deformations of shell-like lattices structures defined in a mono-clinically convected coordinate description to deal with arch-lattices deformations. And the governing equations have been developed using the method of disturbed small motions to clarify the stability problem of shell-like lattice structures. Numerical results show that the complex “peninsular shaped instability regions” are in the excitation force field for arch-lattices under given loading conditions and its stability slips suddenly over a threshold point of dynamic equilibrium from the heteronomous state to an autonomous state of self-sustained motions.