梁中复合应力波的传播

采用有限差分法讨论了梁中复合应力波的传播．给出了粘塑性悬臂梁当自由端受突加弯矩载荷作用时梁内复合应力波传播的基本图象。指出，在冲击早期响应阶段．截面横向转动惯性效应起着重要作用，是不可忽视的。标志弹塑性边界的塑性效，一开始由自由端向固定端运动，但在反射卸载波的迎面作用下，会出现回退现象。在波动早期阶段，固定端主要处于弹性变形状态。此外，还对弹塑性梁中复合应力波的控制方程进行了必要的讨论。

PROPAGATION OF COMBINED STRESS WAVES IN THE BEAM

The combined stress waves in the cantilever beam are studied in the paper with finite difference method. The wave patterns in the viscoplastic beam due to bending moment loading at the free end are obtained by numerical simulations. The results show that the rotatory inertia of the cross-section plays an important part at the early stage of dynamic response of the beam, and hence, it must be taken into consideration. Plastic hinge indicates the boundary of elastic and plastic domain moves to the fixed end at first but it will move back due to the interaction of reflected waves. During the early wave motion stage the fixed end is mostly in elastic deformation. Finally, the governing equations of combined stress waves in elastic-plastic beam are also discussed.