We obtained the bending equations of the elastic viscoplastic beam with rectangular cross section and showed the difficulties in solving these equations.

With the aid of the axial stress waves and bifurcation theory,we discuss the dynamic buckling ofsemi-infinite elastic-plastic beams with various end supports.

Theory analysis of viscoelastic beam stochastic response;

A nonlinear dynamic model for a viscoelastic beam under a laterally distributed excitation in a time dependent temperature field was derived,which is based on the constitutive description of Kelvin viscoelastic materials,motion equations and strain-displacement relations of a beam with large deflections.

The unified differential equation of buckling and motion of viscoelastic beams under uniformly distributed follower forces in time domain is established by differential operators.

The pulse vibration with a certain frequence and amplitude was given to a metal deformation system,and the pulse vibration signal was transformed by Fourier method,one demension elasticity-plasticity constructive model and a visco-elasticity plasticity constructive model were built for vibration drawing.