刚塑性模型研究两个可变形结构相碰撞后的大变形和失效

Dynamic plastic response of two deformable structure colliding with each other has been studied. It was verified that a torsional plastic wave of strong discontinuity will be produced when a tube is subjected to a suddenly torsional impact at its free-end. Analytical solutions for different situations have been given and the influences of mass ratio, material parameters and structural parameters on the plastic deformation of the tube were discussed. For the problem of beam system collision, the.deformation mechanisms are complicated. According to the non-dimensional.combinations for different structural and material parameters, nine regions.corresponding to various deformation mechanisms are formed, for which the.severance limit in shear sliding Phase and the complete solutions can be obtained. In the pipe- impact-pipe study, two-stage calculation model of the deformation divided into local collision stage and bending stage were suggested. This makes the equations.of estimating the plastic failure characteristic of pipe-to-pipe impact be simplified without losing the required precision for engineering application. For the problem of.grouped structure impact, an equivalent spring-mass system model was suggested to approximately estimate the partitioning of the energy absorbing by the landing gear during crash process. The results are significant for conducting the crashworthiness design in research of new type helicopters.

以梁、梁系、圆管、管系以及框架结构为分析对象，研究两个可变形结构在相互撞击后的塑性动力响应，包括完全解和模态解分析、考虑二级效应的影响、实验等。预测撞击以后的主动结构与被动结构的瞬态变形和永久变形，特别是塑性功在两受撞结构之间的分配比例，以及塑性功在结构内部的分布，从而与失效准则联系起来，预测动力失效是否会发生。