Modeling and simulation of high-speed passenger train movements in the rail line

In this paper, we propose a new formula of the real-time minimum safety headway based on the relative velocity of consecutive trains and present a dynamic model of high-speed passenger train movements in the rail line based on the proposed formula of the minimum safety headway. Moreover, we provide the control strategies of the high-speed passenger train operations based on the proposed formula of the real-time minimum safety headway and the dynamic model of highspeed passenger train movements. The simulation results demonstrate that the proposed control strategies of the passenger train operations can greatly reduce the delay propagation in the high-speed rail line when a random delay occurs.

Technical Characteristics of the Construction of Qinhuangdao-Shenyang Passenger Special Line and the Inspiration for High-speed Railway

In this article, the features of design and construction of Qinhuangdao Shenyang passenger special line in railroad foundation, tracks, and bridges are described as an emphasis, the reasons for success are analyzed, and the recommendations to tackle the exiting issues are presented as the reference in high speed railway construction.

Length optimization of straight line connecting turnout on main line in high-speed railway station yard

Taking the development of high-speed railway in China as background, and referring to the dynamic theory and wheel-rail contact mode, dynamic analysis model was established, considering the setting position of straight lines and running conditions of train in high-speed railway station yard. Using the established model, and choosing vehicle lateral acceleration and wheel suspension as the evaluation indexes, dynamic characteristic of vehicle traveling in turnout and adjacent area on main line was analyzed, and effects on travelling safety and stability of train aroused by length variation of straight lines were calculated based on analyzing the damping rules of vibration. The results show that, a certain length of straight lines can alleviate the vibration aroused in turnout and curve(turnout), length of straight lines connecting turnouts in different sections on main line was proposed to meet the demand of traveling stability, and shortening or cancelation of straight line for the scale limitation of station yard has less influence on operation safety of train.

Multi-point Contact of the High-speed Vehicle-turnout System Dynamics

The wheel-rail contact problems, such as the number, location and the track of contact patches, are very important for optimizing the spatial structure of the rails and lowering the vehicle-turnout system dynamics. However, the above problems are not well solved currently because of having the difficulties in how to determine the multi-contact, to preciously present the changeable profiles of the rails and to establish an accurate spatial turnout system dynamics model. Based on a high-speed vehicle-turnout coupled model in which the track is modeled as flexible with rails and sleepers represented by beams, the line tracing extreme point method is introduced to investigate the wheel-rail multiple contact conditions and the key sections of the blade rail, longer nose rail, shorter rail in the switch and nose rail area are discretized to represent the varying profiles of rails in the turnout. The dynamic interaction between the vehicle and turnout is simulated for cases of the vehicle divergently passing the turnout and the multi-point contact is obtained. The tracks of the contact patches on the top of the rails are presented and the wheel-rail impact forces are offered in comparison with the contact patches transference on the rails. The numerical simulation results indicate that the length of two-point contact occurrence of a worn wheel profile and rails is longer than that of the new wheel profile and rails; The two-point contact definitely occurs in the switch and crossing area. Generally, three-point contact doesn’t occur for the new rail profile, which is testified by the wheel-rails interpolation distance and the first order derivative function of the tracing line extreme points. The presented research is not only helpful to optimize the structure of the turnout, but also useful to lower the dynamics of the high speed vehicle-turnout system.

AN ANALYSIS METHOD FOR HIGH-SPEED CIRCUIT SYSTEMS

A new method for analyzing high-speed circuit systems is presented. The method adds transmission line end currents to the circuit variables of the classical modified nodal approach. Then the matrix equation describing high-speed circuit system can be formulated directly and analyzed conveniently for its normative form. A time-domain analysis method for transmission lines is also introduced. The two methods are combined together to efficiently analyze high-speed circuit systems having general transmission lines. Numerical experiment is presented and the results are compared with that calculated by Hspice.

Minimizing crosstalk for high-speed and high-density bus systems using the sample-decision method

This paper presents a method based on a sample-decision(SD) circuit to suppress crosstalk and noise for a high-speed and high-density bus system.A method to count the number of times of SD for different length of transmission lines is presented and a bit error rates(BERs) formula is given by the SD circuit.It is shown that for long transmission line systems,multiple SD circuits can improve the BERs significantly.Circuits simulation for single SD method is also done,it is found that when the amplitude peak values of the superposed crosstalk and noise are less than half of the corresponding signal ones,they will be eliminated completely for the cases investigated.

Influence of Random Track Irregularities on Dynamic Response of Bridge/Track Structure/High-Speed Train Systems

Random vertical track irregularities are one of essential vibration sources in bridge, track structure and high-speed train systems. The common model of such irregularities is a stationary and ergodic Gaussian process. The study presents the results of numerical dynamic analysis of advanced virtual models of composite BTT （bridge/ballasted track structure/high-speed train） systems. The analysis has been conducted for a series of types of single-span simply-supported railway composite （steel-concrete） bridges, with a symmetric platform, located on lines with ballasted track structure adapted for high-speed trains. The bridges are designed according to Polish bridge standards. A new methodology of numerical modeling and simulation of dynamic processes in BTT systems has been applied. The methodology takes into consideration viscoelastic suspensions of rail-vehicles, nonlinear Hertz wheel-rail contact stiffness and one-side wheel-rail contact, physically nonlinear elastic-damping properties of the track structure, random vertical track irregularities, approach slabs and other features. Computer algorithms of FE （finite element） modeling and simulation were programmed in Delphi. Both static and dynamic numerical investigations of the bridges forming the series of types have been carried out. It has been proved that in the case of common structural solutions of bridges and ballasted track structures, it is necessary to put certain limitations on operating speeds, macadam ballast and vertical track roughness.

New-concept Design Innovation of Passenger Station Construction for Qinghe Railway Station of the Beijing-Zhangjiakou HSR

Qinghe Railway Station is the largest passenger station along the Beijing-Zhangjiakou HSR and will serve as the originating station of this line during the A 2022 Winter Olympics.It is also one of the eight major passenger stations in.Beijing.During the construction of this station,all units involved in the construction have made their effors to learn and understand the new concept of building up a“well-connected,filly-integrated,environment-friendly,passenger-oriented,economically-efficient,culturally-rich,inelligent and convenient”passenger station in the new era.Qinghe Railway Station of the Beijing-Zhangjiakou HSR was completed and opened to traffic by the end of 2019 through exploration of new-concept design innovation for passenger station construction in the new era,which was widely praised by the general public.The paper summarizes how the new design concept of passenger station construction is innovated and implemented during the construction of Qinghe Railway Station,thus providing a reference for the future construction of passenger stations.

西南山区铁路客运专线隧道底鼓病害变形监测研究

西南山区铁路客运专线具有高桥隧比、沿线地质条件复杂恶劣等特征,在建设和运营过程中易出现各类工程病害。文章基于某隧道底鼓变形病害,设计并开展包含围岩变形、仰拱受力和道床板沉降变形3个监测指标的隧道变形监测方案。通过对监测数据进行分析,获取隧道和围岩受力变形的演化规律,据此提出后续加密轨道几何形位静态、动态检测和衬砌结构贯通裂缝观测、实施列车降速运行等处理措施。相关研究可为该客运专线的安全运营提供有力保障,同时为类似工程隧道病害的监测和整治工作提供有益参考。

800 km客运班线事故特征及情景研究

为降低800 km以上客运班线事故潜在发生性,提高企业安全防控能力,研究分析了800 km以上客运班线事故典型特征,构建事故发生重要情景。基于2014—2020年800 km以上客运班线道路交通事故数据展开致因分析及事故易发情景研究。以人、路、环境为依据,选取关键特征构建了事故特征指标体系。利用决策树模型构建了安全风险模型,探索了运行时段、人因、天气状况、季度、事故发生地区、道路线形、路面状况、节假日情况、春运情况、公路技术等级和公路行政等系统关键因子与翻车、刮擦、碰撞、撞击固定物、追尾、坠车等事故形态间的潜在关系。剖析了事故发生时交通系统内人、路及环境等因素特征及形态,以此构建了800 km以上客运班线的事故易发情景。结果表明:运行时段、人因、天气状况是影响800 km以上客运班线事故发生的关键因子,且与季度、事故发生地区、道路线形、路面状况等因子存在多重耦合关系;节假日情况、春运情况、公路技术等级和公路行政等级不是影响800 km以上客运班线事故发生的关键因子。研究为降低800 km以上客运班线的事故潜在发生性及企业安全防控提供理论依据。未来,道路运输管理部门与道路运输企业应强化安全管理,规范驾驶员安全驾驶行为,普及事故易发情景下的防御性驾驶知识。

客货“共线不共车”模式下地铁货运站点选择

电子商务的蓬勃发展极大增加了城市物流配送和环境保护方面的压力,让地铁承担部分货运功能成为当前解决这一难题的全新思路。本文基于城市地铁运行特征及未来发展趋势,研究客货列车“共线不共车”模式下的地铁货运,并结合地铁系统的运营情况和内部结构,通过建立E-TOPSIS流量筛选模型、集合覆盖模型、混合整数规划的组合模型,对地铁站点进行分析,从而选择合适的站点作为货运站,最终实现地铁客货列车“共线不共车”模式下的货运方案。最后,以北京市通州区为例进行模拟仿真,找出通州区可开展货运的地铁站点,对地铁货运站点选择的方法进行了验证。

铁路客车技术整备所线路配置规模研究

合理确定铁路客车技术整备所的整备线和车底停留线配置规模,对于节约用地和降低工程投资非常重要。TB 10029—2009《铁路客车车辆设备设计规范》第4.3.2条规定,按入所列车数量确定线路数量,并给出相应的计算表。结合规范修订工作,采用线性回归法和概率分析法对线路配置规模进行研究,并对该条规定在当前的适用性进行验证。研究结论如下:(1)按照列车运行图确定客车车底出入客车技术整备所的时间,分析其最大车底停留数量,从而确定整备线和车底停留线数量之和的方法,是确定客车技术整备所线路数量的准确方法。(2)按照入所车底数量和配置系数确定线路数量方法可行,全路客车技术整备所计算平均数量与运行图分析法计算结果的误差为0.3%~7.5%,符合性较好。(3)将3种计算方法应用到具体铁路客车整备所时,全路各所的均方根误差为25%~27%,该误差受运行图编制主客观因素影响,由各客运站列车终到/始发时间分布规律差异造成,可通过运行图调整来适应。

数字化公交为导向的常州公交客流提升策略研究

受社会和经济等因素的影响,目前地面公交客流出现不同层次的下降,如何深入挖掘制约客流的影响因素,针对不同的具体问题提出相对应的客流提升措施,是提高地面公交的行业竞争力,提升地面公交在居民出行中比例的重要策略。本文通过对居民出行调查和公交满意度调查,深入分析客流下降的原因,并结合公交乘客交通需求调查数据,以数字化公交为导向,从智能化采集数据、灵活化公交线路、数字化线网布局和信息化定制服务等方面提出改善措施。

客运专线大吨位预制箱梁施工技术研究

箱梁在客运专线铁路桥梁中起着重要的承载作用。为此,研究客运专线大吨位预制箱梁施工技术,以满足越来越高的施工要求。从梁场规划与布置、预制箱梁制作、预制箱梁移运架3个方面设计客运专线大吨位预制箱梁施工工艺。结果表明:随着时间的增加,各个测点的电通量均小于1000 C,说明箱梁抗渗能力强;随着冻融循环次数的增加,弹性模量相对值均未超过施工标准且质量损失变化较小,说明箱梁的抗冻性强;随着荷载的增加,箱梁的挠度在不断增加,当加载到最终最大荷载时,挠度仍小于10 cm,说明该箱梁的抗变形能力强,满足施工标准。

考虑电气化铁路接入的山区电网可靠性评估研究

作为大功率、强冲击的移动负荷,电气化铁路接入山区电网后将导致电网线路功率在短时内重新分布,可能引发线路可靠性下降等后果。为此,该文提出一种考虑电气化铁路接入的山区电网可靠性评估方法。首先,考虑途径山区的电气化铁路客货共线的特点,基于列车牵引计算模拟牵引负荷的随机波动性;然后分析牵引负荷对电网潮流的影响;进一步建立线路故障模型对牵引负荷接入后的线路可靠性指标进行计算,量化评估山区电网的可靠性水平;最后,定义线路薄弱度指标对山区电网薄弱环节进行筛选,并提出相应措施以提升电网可靠性。通过算例对比分析优化前后两种情况下的电网可靠性指标,验证了该文所提方法的正确性与有效性。

2023年中国内地城市轨道交通运营线路概况

截至2023年底,中国内地共有28个省份的59个城市开通城轨交通运营线路338条,运营线路总规模达11 232.65 km,其中,地铁线路8 547.67 km,占比76.10%,全自动运营线路1 052.43 km,占已投运线路总里程的9.37%。2023年当年共新增城轨交通运营线路53条(段),新投运线路总长度884.55 km,其中,新增地铁线路539.50 km,新增全自动运行线路252.79 km。新增运营线路共涉及7种系统制式,分布在30座城市中,其中有3座城市为2023年首次运营城轨交通。2023年全年完成客运量再创历史新高,日均客运量首次突破8 000万人次。

城市轨道交通网络跨线列车开行方案优化模型研究

通过开行跨线列车减少乘客换乘次数可有效提升城市轨道交通运输服务水平,本文结合线网客流特征提出跨线方案备选方法,构建跨线列车开行方案优化模型。首先,根据研制的出行路径推算系统分析线网全日各类客流量及比例,确定线网跨线列车的跨线次数,获得备选跨线长交路集;其次,以乘客换乘次数最小化为目标构建满足运营基本条件和跨线能力约束的跨线列车开行方案模型,并嵌套基于发车频率客流分配的改进遗传算法求解,获得本线交路和跨线交路的开行频率;最后,以某城市轨道交通线网为例,研究跨线列车开行方案的优化效果。结果表明:在换乘站开行跨线长交路,全网换乘乘客总换乘次数减少了2.02%~5.97%,降低乘客换乘时间和线网换乘系数,同时直达客流增加了1.58%~4.58%;跨线长交路在衔接线路上承担小交路以补充断面运力,减少本线交路列车的开行频率,可减少线网的上线列车总数和列车正线走行公里数;此外,当换乘站的换乘客流量较高时,跨线长交路因衔接线路上本线交路列车开行频率较高而无法实施,且随着跨线交路开行频率接近跨线能力上限,运营服务水平的提升效果呈逐渐降低趋势。

在役客运专线常见跨径简支箱梁运营性能试验研究

为评价客运专线在役常见跨径简支箱梁在正常运营条件下的安全性和适用性,选择31.5 m跨径简支箱梁为对象,研究简支箱梁动力响应。研究结果表明:时速250 km/h及以下动车组作用下,在役31.5 m跨径简支箱梁跨中横向振幅、横向加速度在箱梁不同部位的振型一致,箱梁顶面位置与梁内底板位置处跨中横向振幅大小基本一致,竖向振幅略大。但各项运营性能参数均满足《高速铁路桥梁运营性能检定规定(试行)》的相关要求。

轨道交通机场专线客运服务标准化研究

轨道交通机场专线是专门服务大型机场的一类特殊线路,其功能定位、客流主体、客流特征、服务标准与市区普通的轨道交通线路存在差异,目前尚缺乏针对此类轨道交通专线的客运服务标准。为更好地满足机场客流的快速集散需求、提高机场专线客运服务质量,有必要制定与之匹配的客运服务标准。首先,从客流结构、线路技术条件、乘客出行需求等角度分析轨道交通机场专线运营服务的特殊性;其次,梳理现有轨道交通客运服务标准,阐述轨道交通机场专线客运服务标准建立的必要性;最后,从标准编制原则、标准框架设计及运营服务重点内容等方面给出客运服务标准的编制建议。研究成果以期为轨道交通机场专线客运服务标准的编制提供参考。

铁路客运站占线程序图自动化推演系统的开发与应用

为改善铁路客运站基于计算机手动绘制占线程序图的现状,提高客运站日常工作绘图效率,确保客运站到发线运用方案编制的合理性,设计了铁路客运站占线程序图自动化推演系统。构建占线程序图动态绘制算法及仿真流程,实现占线程序图动态绘制、到发线运用方案实时评价及机车车辆作业过程推演。在中国铁路沈阳局集团有限公司大连站的仿真应用表明,该系统简化了占线程序图绘制过程,可实时判断并量化评价方案中存在的冲突,为客运站工作人员编制、优化到发线运用方案提供参考。