【作者】 贾颖绚；

【导师】 刘维宁；

【作者基本信息】 北京交通大学 ， 城市轨道工程， 2009， 博士

【摘要】 列车运行会对周边环境产生振动和噪声污染,包括对周边的居住人群、建筑结构物、精密仪器,既有线路,古代建筑群等产生影响,随着地铁网络密集度不断增加,列车振动引起的环境问题成为国内外关注的热点。城轨交通中地铁列车引起的振动,是一个车辆-轨道-隧道-地层的整体系统。其中车辆簧下质量直接影响轮轨接触力,是激发振动的主要振源;隧道结构和地层是振动传播的主要介质。各子系统相互作用、相互耦合,使得地铁列车振动问题异常复杂,必须将理论解析、实地测试和数值模拟有效地结合起来,才能取得良好的结果。因此,本文在国家自然科学基金重点项目“城市轨道交通引起的环境振动及防治对策研究(项目编号:50538010)”和“地铁列车运行引起的隧道及自由场动力响应数值预测模型研究(项目编号:50848046)”的支持下,采用理论分析、现场测试和数值模拟等多种研究手段,得到基于解析的车轨耦合模型,并针对北京地铁5号线的地表振动响应测试,采用MIDAS/GTS软件建立三维动力有限元数值模型进行了仿真计算,对比验证计算模型的正确性与可靠性,并分析了列车振动荷载下地表的动力响应规律,进而通过正交试验法进行数值模拟,对地表振动的影响因素进行了大量的参数分析,取得了以下主要研究成果:(1)从理论的角度建立了一个基于解析的车辆.轨道耦合模型系统,该系统考虑整车模型、无限长轨道结构、轨道不平顺、轮轨接触等因素。在车轨耦合的无限长轨道结构中,通过轨枕的周期性,将无穷域时间空间的积分问题转换为“车轨耦合基本单元”频率域分量的叠加问题,得到了轨道结构任意观察点的动力响应的解析解,从而可以获得了任意行车速度、任意车型荷载、任意轨道结构下的列车动荷载计算的通用理论模型;整个求解过程都是在解析推导下完成的,各物理量均用矩阵和向量来表示,并且在波数.频域内进行的,这对分析整个系统结构的动力响应的频率特性提供了很大方便。(2)编制了完善的车轨耦合解析模型软件包TMCVT,通过计算值与实测值的对比,验证了该软件计算结果的正确性。从而可以方便的研究车辆和轨道相互作用的动力问题。(3)以北京地铁5号线宋家庄.刘家窑区段为背景,进行不同线路条件(圆曲线、缓和曲线、直线),不同扣件型式(DTVI2扣件、Vanguard扣件)的地表振动现场测试,随后通过建立的隧道-地层系统有限元分析模型,从时域、频域以及振动衰减规律多个角度,分析了其地表的振动响应,并与实测资料进行对比,验证了预测模型的可靠和合理性。(4)根据建立的理论模型和有限元模型,采用正交设计的方法,对振动的各影响因素进行参数分析。应用4因素3水平的正交表得到的9种解析荷载,作为激励源作用在隧道.地层动力有限元数值模型上,分析其计算结果,得到地表的振动响应特性及传播规律,研究了不同参数下(轨面埋深,扣件型式,行车速度,隧道犁式)对地表振动影响的显著件辉席。更多还原

【Abstract】 Along with the fast growth of the rail transit network, the metro train induced ground-borne vibration is more and more seriously concerned as most of the line pass under through densely inhabited district, especially to nearby residents, sensitive instrumentations, historic buildings and adjacent structures etc.The problem of the vibration generated by urban rail transit can be seen as an integrated system of vehicle-track-tunnel-stratum, which can be studied from the following sub-systems: vehicles, tracks, tunnel linings, soil strata. Thereinto, vehicle-unsprung mass directly influence on contact forces between wheel and rail, which is the main excitation source of vibrations; while tunnel linings and soil strata are the main mediums for vibration propagation. The sub-systems mentioned above are of interacting and intercoupling, which makes this problem to be extremely complicated. Therefore, it is difficult to evaluate and predict the metro train-induced vibration by only one method; good results should be attained by combination of theoretic analysis, field measurement, empirical estimation and numerical simulation efficiently.This Ph.D thesis is supported by the projects of Natural Science Foundation of China named Research on the Environmental Vibration Induced by Urban Rail Transit and its Countermeasure (No:50538010) and Research on the Numerical Prediction Models for Dynamic Responses of Tunnel and Free Field Ground by Running Metro Trains (No:50848046). Firstly, by the methods of theoretic analysis, an analytical model of coupled with vehicle-track is established. Furthermore, according to the field measurement of ground-borne response of metro Line 5 in Beijing, 3D dynamic FE models are created by software MIDAS/GTS, which to validate and verify the veracity and reliability of analytical and numerical models, and to analyze the vibration propagation for the ground-borne vibration; Finally, through the orthogonal test and numerical simulation method, 9 dynamic loads and 3D FE models are established to study the influence on ground-borne vibration of different factors and parameters . The main achievements include:(1) An analytical model system coupled with vehicle & track is established. In this system, the factors of a whole vehicle model, infinite track structure, track irregularity and wheel-rail Hertz contact are all taken into account. In the infinite track structure, based on the periodicity of sleepers, the integral problem in boundless time-space domain has been transferred to a superposition problem with "coupled vehicle and track basic cell" in frequency domain. Moreover, an analytical solution of dynamic response at random receiver point on tracks is derived, which can get from a general theoretical model for dynamic vehicle load of any vehicle speeds, any vehicle types and any track structures. The whole solving process is based on analytical derivation and every physical quantity is represented by matrixes and vectors. The process is finished in wave number-frequency domain, which provides great convenience for analyzing the frequency characteristic of whole dynamic system.(2) A complete software package TMCVT is programmed. Compared with in-situ measurement values, the results calculated by TMCVT are proved to be correct. Thereby, TMCVT can be used to study the problem of dynamic interaction with vehicle and track.(3) The main objective of this paper is to describe the results of in situ measurements about ground-borne vibration that have been performed with three different line status (curve, adjust curve, straight line), two different mitigation measures (simple DTVI2 fastener, Vanguard fastener) at three sites of Beijing metro Line 5 (Songjiazhuang-Liujiayao). Especially the time history and frequency properties of the vibration were been studied. And then, a tunnel-stratum 3D FE model is built and caculated, which ground-borne vibration responses are analyzed and simulated from different viewpoints, including time domain, frequency domain and vibration attenuation regulation. Compared with the in-situ measurement values, the calculated results are proved to be correct and the vehicle-track-tunnel-stratum model is also to be reliable and reasonable.(4) According to the theoretical model and FEM which mentioned above, an orthogonal test table under 4 factors and 3 levels is designed for analyzing different influence factors on the train-induced ground vibration. Nine analytical dynamic forces are applied on the tunnel-stratum FE models to simulate and study the the ground borne vibration. From different points including time domain, frequency domain and vibration attenuation regulation, the dynamic responses on ground surface and the propagation regulation are obtained and analyzed. Furthermore, the influence degree of different parameters (embedded depth of track surface, type of fastener, vehicle speed and tunnel form) to ground-borne vibration has also been presented.更多还原