Abstract:Because of the coupling of dynamic buckling and stress wave propagating, the traveling time of the stress wave becomes one of the parameters in dynamic buckling caused by stress waves. So the real displacement and the adjacent displacement of the dynamic buckling caused by stress waves occur at different time and different area, which make it unsuitable for using of the integral variational principle in derivation of governing equations for dynamic buckling of structure under compression wave; By use of the conservation law of energy transformation in the instant course of buckling, the governing equations, boundary conditions and supplementary restraint-equation at the compression-wave front of column under elastic compression wave are derived; At last, the physical meaning of the supplementary restraint-equation is studied, and the appearance of the supplementary restraint-equation is attributed to the coupling of dynamic buckling and stress wave propagating.