摘要
Random dynamic responses caused by the uncertainty of structural parameters of the coupled train-ballasted track-subgrade system under train loading can pose safety concerns to the train operation.This paper introduced a computational model for analyzing probabilistic dynamic responses of three-dimensional(3D)coupled train-ballasted track-subgrade system(TBTSS),where the coupling effects of uncertain rail irregularities,stiffness and damping properties of ballast and subgrade layers were simultaneously considered.The number theoretical method(NTM)was employed to design discrete points for the multi-dimensional stochastic parameters.The time-histories of stochastic dynamic vibrations of the TBSS with systematically uncertain structural parameters were calculated accurately and efficiently by employing the probability density evolution method(PDEM).The model-predicted results were consistent with those by the Monte Carlo simulation method.A sensitivity study was performed to assess the relative importance of those uncertain structural parameters,based on which a case study was presented to explore the stochastic probability evolution mechanism of such train-ballasted track-subgrade system.
列车荷载作用下有砟轨道-路基耦合系统结构参数的不确定性引起的随机振动对行车安全的影响不可忽略。本文提出了一种基于概率密度演化理论的三维列车-有砟轨道-路基耦合系统随机振动概率仿真分析模型,该模型可同时考虑轨道随机不平顺、道砟层和路基层随机刚度、随机阻尼等耦合效应,为列车-轨道-路基系统随机振动分析提供了一种全新的计算分析方法。采用数论方法对多维随机参数进行代表性离散数组点设计。结果表明,与蒙特卡罗模拟方法相比,概率密度演化模型开展随机振动分析更为准确、高效。基于算例开展了多维随机参数的敏感性分析,系统地评估了不确定结构随机参数的相对重要性,并在此基础上探讨了列车-轨道-路基系统的随机概率演化机制。
作者
MAO Jian-feng
XIAO Yuan-jie
YU Zhi-wu
Erol TUTUMLUER
ZHU Zhi-hui
毛建锋;肖源杰;余志武;Erol TUTUMLUER;朱志辉(School of Civil Engineering,Central South University,Changsha 410075,China;National Engineering Laboratory for High-Speed Railway Construction,Changsha 410075,China;Key Laboratory of Engineering Structures of Heavy Haul Railway of Ministry of Education,Central South University,Changsha 410075,China;Department of Civil and Environmental Engineering,University of Illinois at Urbana-Champaign,Urbana,IL 61801,United States)
基金
Projects(51708558,51878673,U1734208,52078485,U1934217,U1934209)supported by the National Natural Science Foundation of China
Project(2020JJ5740)supported by the Natural Science Foundation of Hunan Province,China
Project(KF2020-03)supported by the Key Open Fund of State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures,China
Project(2020-Special-02)supported by the Science and Technology Research and Development Program of China Railway Group Limited。
