上海地铁1号线车辆转向架寿命预测数值分析

Lifetime Prediction of the Bogie Frame of Shanghai Metro Line 1 by 3D FEM

上海地铁1号线自1992年运营至今,在列车检修作业中多次发现列车动车转向架构架出现裂纹,远远达不到1号线车辆技术规格书中30年使用寿命的要求。针对地铁转向架结构特点和受力特点,对地铁转向架进行了三维有限元计算,并且利用名义应力疲劳设计法对电机吊座应力集中部位进行了分析,得到反映结构疲劳强度性能的S-N曲线,进行了寿命预测。计算结果表明:转向架构架产生的裂纹主要是由于疲劳强度不足产生的疲劳裂纹,垂向振动和横向振动是引起裂纹的主要因素。由于横向振动出现的频率远高于垂向加速度,其损伤量甚至大于垂向振动损伤量。

Multiple cracks were found in the vehicle bogies of Shanghai metro line 1,which began its operation in 1992,so that the life of the vehicle bogies is much less than 30 years promised by the technical specification.This paper simulated the stress of vehicle bogie by 3D FEM to present the distribution of every stress concentration point.The Goodman fatigue diagram was drawn based on the stress concentration points and the life of the motor bracket of the bogie was predicted by the revised Miner theory.This paper concluded that the bogie cracks of Shanghai metro line 1 are contributed by the overburden fatigue load, and ignoring the lateral vibration load in the design of the vehicle bogie is the important cause for that the bogie cracks occurred far earlier than the designed life time. The computed frequency from the lateral vibration is much higher than that from the vertical vibration so the damage by the lateral vibration to the vehicle is more than by the vertical vibration.