Nonlinear Dynamical Stability of the Lattices with Initial Material and Geometric Imperfection

摘要

As the lattices had sensitive to the initial material and geometric imperfection,structure imperfections and physical imperfection are important nonlinear dynamical stability of the system.The lattices with two imperfections were frail to collapse under rainstorm,blizzard and earthquake.So a nonlinear dynamic model of the lattices with coupling the initial imperfection and initial damage was obtained to reveal the plenty dynamics characteristic.Firstly it can be taken deformation as initial imperfection and nonlinear dynamic model of the lattices with initial damage was given.Then the problem of local stability at the equilibrium of the system was discussed by exponent Eloquent under different initial conditions and parameter.Finally theoretically critical condition of chaotic motion was given using the Melnikov function method.The chaos motion of the lattices with initial material and geometric imperfection was simulated by computer numerical emulation under nonlinear forced vibration.And it was founded that the initial initial material and geometric imperfection made the chaos motion of the system easily occur.