基于IDEPSO-SS的多工况转向架构架可靠性分析

基于子集模拟(Subset Simulation,SS)方法求解结构失效概率,再采用改进差分进化粒子群算法(IDEPSO)优化每层样本个数和初始条件概率,以获得单工况下结构最优失效概率,并结合几何分析确定联合失效概率,计算多工况下结构失效概率,确定最优失效次序。以某型转向架构架为研究对象,先采用SS方法建立构架各工况下每层样本个数和初始条件概率关于结构失效概率的响应面代理模型;再采用IDEPSO算法计算各工况下每层样本个数和初始条件概率的最优值,计算构架单工况下最优失效概率;最后,采用几何分析确定多工况下的联合失效概率,并结合二阶窄边界法和最优准则获得构架多工况下最优可靠度和最优失效次序。结果表明:基于IDEPSO-SS获得的单工况构架最优失效概率,在保证计算精度的同时,较传统方法计算效率提高了96%;最优失效次序下构架的多工况失效概率高于传统方法,提高了多工况转向架构架可靠性分析的准确性。

IDEPSO-SS Based Reliability Analysis of Bogie Frame under Multiple Load Cases

The structural failure probability was solved based on the method of subset simulation(SS),and then the improved differential evolution particle swarm optimization(IDEPSO)algorithm was used to optimize the number of samples in each layer and the initial condition probability,so as to obtain the optimal structural failure probability of the structure under single load case.Combined with geometric analysis,the joint failure probability was determined,the structural failure probabilities under multiple load cases were calculated and the optimal failure order was determined.Taking a certain type of bogie frame as the research object,firstly,the response surface surrogate model of the number of samples and the initial condition probability of each layer under each load case with respect to the structural failure probability was established by using SS method.Then the IDEPSO algorithm was used to calculate the optimal values of the samples and the initial condition probability of each layer under each load case as well as the optimal failure probability of the frame under single load case.Finally,the geometric analysis was used to determine the joint failure probability under multiple load cases,and the optimal reliability and failure order of the frame under multiple load cases were obtained by combining the second-order narrow boundary method and the optimal criteria.Results show that the computational efficiency of the proposed method to calculate the optimal failure probability of bogie frame under single load case is increased by 96%compared with traditional method,at the same time of ensuring the accuracy of calculation.Under the optimal failure order,the failure probability of bogie frame under multiple load cases is higher than that of traditional method,which improves the accuracy of the reliability analysis of bogie frame under multiple load cases.