轴向冲击载荷下圆柱壳的塑性动力屈曲

Plastic dynamic buckling of cylindrical shells under axial impulsive loads

对于轴向冲击载荷下圆柱壳的轴对称塑性动力屈曲问题,将临界应力和屈曲惯性项指数参数作为双特征参数求解.由相邻平衡准则导出失稳控制方程、边界条件和波阵面上的连续条件.由失稳瞬间的能量转换和守恒准则,导出波阵面上的一个屈曲变形约束方程.由此得出定量求解2个特征参数和动力屈曲模态的完备定解条件.关于屈曲应力和屈曲波数的理论计算结果与已有实验吻合良好.

The critical stress and the exponential parameter of the buckling inertia term are treated as the twin characteristic parameters for the axi-symmetric plastic dynamic buckling of cylindrical shells under the axial impulsive load. The governing equations, boundary conditions and continuity conditions are derived by the adjacent-equilibrium criterion. The supplementary restraint equation of buckling deformation at the fronts of axial compression waves is obtained in terms of the criterion of energy transformation and energy conservation in the transient process of buckling. Thus, the necessary and sufficient conditions are given for quantitatively determining the twin characteristic parameters and buckling deformation modes. The critical stress and axial buckling-wave-number predicted by the (theoretical) analysis is in good agreement with existent experimental results.