基于线路试验的转向架构架疲劳可靠性分析  

Fatigue Reliability Analysis of Bogie Frame Based on Line Test

作　　者：智鹏鹏 陈秉智[2] 李永华[2] 王悦东 ZHI Peng-peng;CHEN Bing-zhi;LI Yong-hua;WANG Yue-dong(Yangtze Delta Region Institute(Huzhou),University of Electronic Science and Technology of China,Zhejiang Huzhou 313001,China;School of Locomotive and Rolling Stock Engineering,Dalian Jiaotong University,Liaoning Dalian 116028,China;Institute of Electronic and Information Engineering in Guangdong,University of Electronic Science and Technology of China,Guangdong Dongguan 523808,China)

机构地区：[1]电子科技大学长三角研究院(湖州),浙江湖州313001 [2]大连交通大学机车车辆工程学院,辽宁大连116028 [3]电子科技大学广东电子信息工程研究院,广东东莞523808

出　　处：《机械设计与制造》2023年第5期215-220,225,共7页Machinery Design & Manufacture

基　　金：广东省基础与应用基础研究基金(2021A1515110308)。

摘　　要：为提升转向架构架疲劳可靠性分析的准确性,预防等效应力和疲劳强度随时间变化导致的疲劳失效,提出一种基于等效时变动态应力-强度干涉模型的疲劳可靠性分析方法。对预评估转向架构架进行线路试验跟踪测试,采用双参数雨流计数法对实测随机应力-时间历程进行处理,建立用于疲劳可靠性分析的应力谱,并根据Miner法则和疲劳损伤等效原则获得对称循环等效应力。结合连续时间模型和伊藤引理,构建等效应力和疲劳强度的一维布朗运动方程,并以疲劳强度大于等效应力为可靠性判据,提出转向架构架的等效时变动态应力-强度干涉模型,分析构架服役寿命与疲劳可靠度的关系。以某型号转向架构架横梁与吊座连接处为对象,基于实测线路试验数据,验证方法的有效性。结果表明:转向架构架服役1200万公里的疲劳可靠度为74.46%,较传统方法偏于安全。由于考虑了等效应力和疲劳强度的时变性与动态性,使得分析结果更加准确,可为焊接结构的疲劳可靠性评估与结构优化提供参考。In order to improve the accuracy of fatigue reliability analysis of the bogie frame and prevent the fatigue failure caused by the change of equivalent stress and fatigue strength with time,a fatigue reliability evaluation method based on the equivalent time-variant dynamic stress-strength interference model is proposed.The line test tracking test is carried out on the pre-evaluation bogie frame,and the measured random stress-time history is processed by using the two parameters rain flow counting method to establish the stress spectrum for fatigue reliability analysis.The equivalent stress of the symmetrical cycle is obtained according to Miner's rule and fatigue damage equivalent principle.The continuous-time model combined with the Ito lemma is adopted to establish the one-dimensional Brownian motion equation of equivalent stress and fatigue strength.Taking the fatigue strength greater than the equivalent stress as the reliability criterion,an equivalent time-variant dynamic stress-strength interference model of the bogie frame is proposed to analyze the relationship between the service life and fatigue reliability of the frame.Based on the measured line test data,the validity of the method is verified by taking the joint between the crossbeam and the hanger of a bogie frame for the object.Results show that the reliability of the bogie frame with 12 million km service is 74.46%,which is safer than the traditional method.As considering the time-variant and dynamic of equivalent stress and fatigue strength,the analysis results are more accurate,which can provide a reference for fatigue reliability evaluation and structural optimization of welded structures.

关 键 词：应力-强度干涉模型 转向架构架 疲劳可靠性 疲劳强度 

分 类 号：TH16[机械工程—机械制造及自动化] U271.92[机械工程—车辆工程]