【作者】 陈嵘；

【导师】 王平；

【作者基本信息】 西南交通大学 ， 道路与铁道工程， 2009， 博士

【摘要】 高速铁路对线路的平顺性要求严,高架桥、长大桥多为其主要特征,车站咽喉区位于桥梁上的可能性较普通铁路大得多。作为限速关键设备的高速道岔铺设于桥梁上,岔桥结构发生剧烈的动力相互作用,从而降低高速列车桥上过岔时的安全性与平稳性。随着我国客运专线和高速铁路的建设,快速及高速行车条件下车辆与桥上道岔的动态相互作用问题成为亟需开展的基础性课题之一。本文在参考国内外车桥振动理论与道岔动力学研究资料的基础上,将机车车辆、道岔区轨道与桥梁视为一个整体大系统,以车辆动力学、道岔动力学、桥梁动力有限元方法为基础,以岔区轮轨关系、岔桥关系为联系纽带,应用数值仿真的方法来研究高速行车条件下道岔区轨道及桥梁结构的动力特性、行车的安全性和平稳性,为高速铁路桥上无缝道岔的设计方案评估和参数优化提供理论支撑。主要研究工作如下：1.建立车辆-道岔-桥梁耦合振动系统模型将机车车辆视为一个由悬挂弹簧和阻尼联系起来的7刚体(1个车体、2个构架、4个轮对)振动系统,每个刚体具有点头、摇头、侧滚、沉浮和横移5个自由度,整个车辆系统共有35个自由度。在综合高速道岔结构特点的基础上,建立起包含转辙器、连接部分和辙叉三部分的完整道岔动力学模型,模型中考虑钢轨截面型式变化、顶铁接触传力、间隔铁高强联结、滑床台非线性支承等因素;将轨枕或支承块视为刚体并考虑其垂向、横向及转动自由度,无砟轨道板的垂向振动按弹性地基上的等厚度矩形薄板考虑,而横向视为刚体运动。运用动力有限元方法将桥梁结构离散化。2.详细论述车辆-道岔-桥梁动态相互作用原理并建立相应分析理论、编制通用计算程序DATTB综合应用道岔区多变的轮／岔接触几何关系、轮轨Hertz非线性弹性接触理论、轮轨蠕滑理论、岔桥相互作用关系,详细论述了车辆-道岔-桥梁动态相互作用原理。以高速道岔结构及状态不平顺作为系统的主要激振源,根据离散系统动力问题的Hamilton变分原理和“对号入座”法则建立起车-岔-桥耦合振动分析理论,并编制出相应动力学仿真通用程序DATTB。3.高速铁路岔桥结构运用安全性以及行车平稳性评估标准探析提出以列车桥上过岔的安全性及平稳性、道岔与桥梁的强度和稳定性作为桥上道岔的动力评估准则,对国内外有关机车车辆、道岔及桥梁的动力学性能评价指标,如轮轨垂、横向力、轮轴横向力、尖轨及心轨开口量、尖轨及心轨动应力、脱轨系数、轮重减载率、车体振动加速度、平稳性指标、桥梁挠度、桥梁自振频率、桥梁横向振幅、桥梁振动加速度等进行了归纳整理。4.车-岔-桥耦合振动试验研究应用DATTB对浙赣线湄池特大桥上200km／h提速改进型60kg／m钢轨12号有砟道岔进行动力学评估,通过仿真结果与实测结果的对比分析,验证了DATTB的可靠性。同时,桥上道岔与路基上道岔的动测结果对比分析表明,桥上道岔区轮轨动力相互作用远较普通路基上道岔区强烈。5.高速车辆与桥上道岔的动态相互作用规律研究系统研究车辆、道岔和桥梁的各种可变因素对车-岔-桥耦合振动的影响,揭示出高速车辆与桥上道岔的动态相互作用规律,并提出了高速铁路桥上无缝道岔动力设计指导原则。优化的道岔区轮轨关系和轨道刚度、合理的桥梁竖向刚度和岔桥相对位置是保证高速列车桥上过岔安全性与平稳性的关键。6.车辆-道岔-桥梁耦合振动理论的工程应用以郑西客运专线无砟轨道多种跨度布置连续梁桥上铺设法国COGIFER时速350公里18号道岔和厦深客货混跑铁路有砟轨道(48+2×80+88+48)m连续梁桥上铺设中国自主研发的时速250公里30号道岔的动力学评估为例阐述了车辆-道岔-桥梁耦合振动理论的实际应用。更多还原

【Abstract】 High speed railway is characterized by more viaducts and long bridges than existing railway line, and throat area of railway station is more possible to be set on a bridge, because there are strict requirements for regularity of high speed railway. High speed railway turnout as a key speed-limit equipment is set on bridge, and it results in violent dynamic interaction between turnout and bridge structure, so the safety and comfort of a train passing a turnout on bridge are decreased. With the construction of Passenger Dedicated Lines (PDLs) and high speed railway in China, it is one of basic issues to study the dynamic interactions between vehicle and turnout on bridge under the high speed running condition. According to the reference research data of vehicle-bridge vibration theory and turnout dynamics at home and abroad, vehicle, track of turnout zone and bridge are viewed as an integrated system. Based on vehicle dynamics, turnout dynamics and bridge finite element method, with wheel/rail relation and turnout/bridge relation as connection links, a numerical simulation method is applied to study the dynamic characteristics of track in turnout zone and bridge structure, running safety and comfort under high speed running condition, so as to provide theoretical support for design scheme estimation and parameter optimization of welded turnout on bridge of high speed railway. Main research works are as follows:(1) Vehicle-turnout-bridge coupling vibration system modelA vehicle is viewed as a 7 rigid-body (1 car-body,2 bogies, and 4 wheel-sets) vibration system connected by suspension spring and damper. Each rigid-body has 5 degrees of freedom (DOFs), i.e. yaw, pitch, rolling, shaking and vertical vibration, and total DOFs of the whole vehicle amounts to 35. A complete turnout dynamic model, which contains switch proper, linking parts and frog, is established by integrating structure characteristics of high-speed turnout. Such factors as rail section variation, jacking block contact force, spacer block high strength connection, and sliding platform nonlinear support are also taken into account. Sleeper or support block are viewed as a rigid-body which considers its vertical, transverse and rotation DOFs; vertical vibration of ballastless track slab is considered as an equi-thickness rectangular thin plate on elastic subgrade, while its transverse vibration is viewed as rigid-body movement. Dynamic finite element method is applied to the discretization of bridge structure.(2) Dynamic interaction principle, coupling vibration analysis theory and corresponding all-purpose program DATTBWith comprehensive application of following theories, such as wheel/turnout multi-point dynamic contact relation, wheel/rail Hertz nonlinear contact theory, wheel/rail creep theory, turnout/bridge interaction, the principle of vehicle-turnout-bridge dynamic interaction is discussed in detail. Viewing high speed turnout structure and state irregularity as main excitation, a vehicle-turnout-bridge coupling vibration analysis theory is established by using Hamilton Variation Principle and’Numbered Seat Principle’. Related dynamics simulation all-purpose program DATTB is completed.(3) Analysis on evaluation standard for high speed turnout/bridge structure application safety and running comfortThe safety and stationarity when train passing turnout on bridge, strength and stability of turnout and bridge are viewed as the dynamic evaluation guide line of turnout on bridge. Dynamic performance evaluation indexes of vehicle-turnout-bridge at home and abroad are all concluded, i.e. wheel/rail vertical and transverse force, wheel axle transverse force, opening of switch and nose rail, dynamic stress of switch and nose rail, derailment coefficient, rate of wheel load reduction, car-body vibration acceleration, ride index, bridge deflection, bridge natural frequency, bridge transverse amplitude and bridge vibration acceleration.(4) Experimental study on Vehicle-turnout-bridge coupling vibrationAiming at 200km/h speed 60kg/m rail 12# ballasted turnout on Meichi large bridge of Zhe-Gan line, dynamics assessment is explored by applying DATTB, whose reliability is testified through comparison between simulation results and experimental results. Meanwhile, comparison analysis of dynamic tests between turnout on bridge and turnout on subgrade shows that wheel/rail dynamic interaction of turnout zone on bridge is more violent than that of ordinary turnout on subgrade.(5) Research on laws of dynamic interaction between high speed vehicle and turnout on bridgeBy studying influences of variable factors on vehicle-turnout-bridge coupling system, the laws of dynamic interaction between high speed vehicle and turnout on bridge are revealed and guide principle for dynamic design of welded turnout on bridge of high speed railway is suggested. Optimized wheel/rail relation of turnout zone and track stiffness, reasonable bridge vertical flexural stiffness and ideal relative position between turnout and bridge are the keys to maintain the safety and comfort of high speed train passing turnouts on bridge.(6) Engineering application of vehicle-turnout-bridge coupling vibration theoryPractical application of vehicle-turnout-bridge coupling vibration theory is discussed on the basis of dynamics evaluations of 350km/h 18# ballastless turnout (French COGIFER) on multi-collocation continuous beam bridges of Zhengzhou-Sian PDL and 250km/h 30# ballasted turnout (China Independent R & D) on (48+2×80+88+48) m continuous beam bridge of Xiamen-Shenzhen mixed passenger and freight railway line.更多还原