摘要
讨论弹性有限长度杆端部受冲击载荷作用，在轴向应为波传播和反射过程中的动态屈曲问题．利用扰动方程的解、端部支承条件和应力波反射前后波阵面相容条件得到了动态屈曲的分叉条件，临界载荷和屈曲模态．数值结果表明：临界载荷有多个分支且随时间增加而降低；由于应力波在端部的反射，使临界载荷进一步下降．这个结果就解释了实验中的一些现象．
In this paper,dynamic of elastic finite-bar,which is impacted on the end by axial step loads,is discussed with the aid of the stress wave propagating and reflecting. Using solutions of the disturbed equations,end conditions and consistence conditions of the wave front in wave propagating aug reflecting,the bifurcation condition of the dynamic buckling,critical buckling load and buckling mode are obtained. The results show that:every branch of critical buckling load decreases with time;since the wave is reflected on the other end of the bar,the critical buckling load decreases further. The results are in agreement with the physical phenomenon in experiments.
基金
国家重点实验室开放基金
