中文摘要：

摘要针对高速客车轻量化不锈钢车体结构动态特性不足的问题，以速度200km／h等级客车不锈钢车体为载体，基于有限元数值模拟仿真平台，建立了车体的精细有限元模型，分析了车体结构的稳定性，得到了不锈钢点焊车体发生屈曲失稳的薄弱部位以及对应的屈曲载荷因子。从结构特点和力流传递的角度，对结构失稳部位进行了分析，并基于仿真结果对车体失稳部位进行了局部结构优化改进。结果表明：改进后的车体在最大载荷状态下失稳部位屈曲载荷因子满足标准中大于1．5的要求，车体结构稳定性得到了显著的提高。

英文摘要：

Against the problem of high--speed passenger lightweight stainless steel carbody structure lacking of dynamic characteristics, taking the speed rating of 200 km/h passenger stainless steel earbody for the research, the detailed carbody finite element model was es- tablished based on the finite element numerical simulation platform, carrying out the linear bulking analysis of the carbody structure to obtain the weak site of the occurrence of instability of the stainless steel spot welding carbody and the corresponding bulking load factor. The instability site of the structure was analyzed from the perspective of the structural features and force flow transmission. The local structure of the site of the vehicle carbody instability was optimized and improved based on the simulation results. The results show that hulking load factor of the instability site of the improved vehicle undering maximum load state is greater than 1.5 to meet the standard, and the stability of carbody structure has been significantly improved.