基于雨流法的汽车底盘件疲劳耐久试验方法研究

Research on Fatigue Durability Test Method for Automobile Chassis Components Based on Rain-flow Counting Method

基于雨流计数统计法,研究了将道路采集时序数据转化为当量伪损伤程度的循环载荷的方法,以及基于副车架各向载荷的模拟试验方法。根据累计疲劳损伤、材料应力-应变迟滞回线等原理,建立了车辆道路载荷谱与室内模拟试验加载谱的相关性转化映射关系。以某车型副车架为例进行了耐久性能试验。结果表明,所提出的转化方法能够在保持载荷累计疲劳损伤的同时,将长时间作用的实际道路谱载荷转化为较短作用时间并易于实现的循环载荷,从而快速、有效地进行室内道路耐久模拟试验。

Based on rainflow counting method, the cyclic load method which transfers time series data into equivalent psudo-damage degree, and the simulative test method based on subframe load were studied. Based on accumulative fatigue damage, material stress-hysteresis strain loop theory, the correlation conversion mapping between vehicle road load spectrum and vehicle interior simulation test loading spectrum was established. Durability performance test was carried out with a vehicle subframe as research object. Test results show that the proposed conversion method can maintain load accumulative fatigue damage, meanwhile it can convert the real road spectrum load into cyclic load, for rapid and effective indoor road durability simulation test.