研究成果

Non-stationary random vibration analysis of a 3D train–bridge system using the probability density evolution method

发布时间:2016/1/29阅读次数:3373次

    祝贺课题组毛建锋博士在期刊 《Journal of Sound and Vibration》发表论文:Zhi-wu Yu, Jian-feng Mao*, Feng-qi Guo, Wei Guo,Non-stationary random vibration analysis of a 3D train–bridge system using the probability density evolution method。论文主要内容为:“Rail irregularity is one of the main sources causing train–bridge random vibration. A new random vibration theory for the coupled train–bridge systems is proposed in this paper. First, number theory method (NTM) with 2N-dimensional vectors for the stochastic harmonic function (SHF) of rail irregularity power spectrum density was adopted to determine the representative points of spatial frequencies and phases to generate the random rail irregularity samples, and the non-stationary rail irregularity samples were modulated with the slowly varying function. Second, the probability density evolution method (PDEM) was employed to calculate the random dynamic vibration of the three-dimensional (3D) train–bridge system by a program compiled on the MATLAB software platform. Eventually, the Newmark-β integration method and double edge difference method of total variation diminishing (TVD) format were adopted to obtain the mean value curve, the standard deviation curve and the time–history probability density information of responses. A case study was presented in which the ICE-3 train travels on a three-span simply-supported high-speed railway bridge with excitation of random rail irregularity. The results showed that compared to the Monte Carlo simulation, the PDEM has higher computational efficiency for the same accuracy, i.e., an improvement by 1–2 orders of magnitude. Additionally, the influences of rail irregularity and train speed on the random vibration of the coupled train–bridge system were discussed.”原文请参见附件。

    毛建锋博士的主要研究方向为基于概率密度演化理论的车-线-桥耦合随机振动分析。他引入(广义)概率密度演化理论,基于物理本质的思想,发展了基于输入激励随机性和结构参数随机性的列车-轨道-桥梁结构耦合系统随机振动模型,分别建立了列车-桥梁垂向系统随机振动模型、列车-桥梁空间系统随机振动模型和基于轮轨关系精细化的高速列车-无砟轨道-桥梁三维空间耦合随机振动模型,逐步验证了应用广义概率密度演化理论进行车桥耦合随机振动分析的适用性、高效性和高精度性,并进行了大量高速列车-无砟轨道-简支桥梁随机动力系统的随机振动仿真计算和结果分析,为我国高速铁路建设提供了全新、可靠的研究思路和技术支撑。并且发展了一系列高速列车-桥梁随机输入激励参数和结构随机参数离散代表样本点集的选取方法,有效提升了车桥耦合随机动力系统响应的计算效率和计算精度。更多关于基于概率密度演化理论的车-线-桥耦合随机振动分析内容请参见附件。

附件:Non-stationary random vibration analysis of a 3D train-bridge system using the probability density evolution method

附件:概率密度演化方法的车桥耦合随机振动