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941.
高铁列车动载作用下路基动力特性及累积变形规律研究   总被引:2,自引:2,他引:0  
为探索列车动载作用下路基的动力特性及累积变形规律,依托沪宁城际铁路工程背景,首先结合现场测试数据对路基沉降超限的原因进行分析,然后建立列车-轨道-路基耦合振动系统三维数值模型,对影响路基动力特性的影响因素(列车速度、基床厚度和刚度、行车方式)进行分析,最后结合室内足尺模型试验,对振动40万次的基床累积变形规律进行分析。结果表明:列车动载作用是运营期路基沉降超限的主要原因之一;列车速度、基床厚度和刚度、行车方式等因素对基床的动应力和动位移均有影响;路基的累积变形随循环加载次数增加而变大,最初振动5万次累积变形增长迅速,而后近似按照线性缓慢发展,振动40万次时的累积变形值为0.78 mm,影响深度约为5 m。  相似文献   
942.
This study presents a more realistic modelling of the maglev-based high-speed railway line in Shanghai, China. Focus is placed on an accurate simulation of the two subsystems: the train subsystem including the magnets and the viaduct subsystem including the modular function units of the rails. The electromagnet force–air gap model with a proportional-derivative (PD) controller is adopted to simulate the interaction between the maglev train via its electromagnets and the viaduct via its modular function units. The flexibilities of the rails, girders, piers and associated elastic bearings are all considered in the modelling of the viaduct subsystem to investigate their effects on an interaction between the two subsystems. By applying the proposed model to the Shanghai maglev line, the essential characteristics of the coupled system can be duly captured. The accuracy and effectiveness of the proposed approach are then validated by comparing the computed dynamic responses and frequencies with the measurement results. It is confirmed that the proposed modelling with a detailed simulation of the magnets and modular function units can duly account for the dynamic interaction between the train and viaduct systems. Moreover, the effects of the inclusion of the flexibilities of the rails, girders and elastic supports to the response of the coupled system are respectively investigated, the results of which prove that their involvements are essential to the accurate prediction of the response of the coupled maglev train–viaduct system.  相似文献   
943.
This paper proposes a mathematical model for the train routing and timetabling problem that allows a train to occasionally switch to the opposite track when it is not occupied, which we define it as switchable scheduling rule. The layouts of stations are taken into account in the proposed mathematical model to avoid head-on and rear-end collisions in stations. In this paper, train timetable could be scheduled by three different scheduling rules, i.e., no switchable scheduling rule (No-SSR) which allows trains switching track neither at stations and segments, incomplete switchable scheduling rule (In-SSR) which allows trains switching track at stations but not at segments, and complete switchable scheduling rule (Co-SSR) which allows trains switching track both at stations and segments. Numerical experiments are carried out on a small-scale railway corridor and a large-scale railway corridor based on Beijing–Shanghai high-speed railway (HSR) corridor respectively. The results of case studies indicate that Co-SSR outperforms the other two scheduling rules. It is also found that the proposed model can improve train operational efficiency.  相似文献   
944.
The design of new pneumatic brakes for rail vehicles or improvements of existing ones can be made better or more efficient by the use of a simulation method. This paper gives a general presentation of the author’s modelling methods used for solving problems relating to railway pneumatic brakes. The brake models in this paper (slightly different from those of other authors) take into account air-wave phenomena including air viscosity, the influence of the brake pipe branches, heat transfer in the brake pipes and reservoirs, air flows in the brake valves and the dynamics of moving mechanical parts. For various simulation purposes, separate partial models with different levels of accuracy were created. Various verifications and identifications of the models were performed with the use of train brake testing facilities, including both in-house and other test stands. A variety of examples of simulation results are presented here.  相似文献   
945.
基于无线通信的无缝漫游模型   总被引:1,自引:0,他引:1  
为了保证列车在高速行驶过程中,与轨旁不同接入点之间进行数据传输的连续性,提出一种利用列车长度特点的无线信号切换模型,通过软件合理调度车头和车尾的信号源,有效避免了新链路的网络连接延迟时间对传输通道的影响,把新链路的网络连接延迟时间压缩为0,实现了列车的无缝漫游。  相似文献   
946.
This paper discusses the use of inerters to improve the stability and performance of a full-train system. First, we construct a 28 degree-of-freedom train model in AutoSim, and obtain a linearised model for analysis in Matlab. Then, the benefits of inerters are investigated by the critical speed, settling time and passenger comfort. In addition, we apply a new mechatronic network for further performance improvement, and synthesise the optimal electrical circuit for experimental verification. From the results, inerters are shown to be effective in improving the stability and performance of train systems.  相似文献   
947.
为了能够有效提高地铁车辆段列车运营管理效率,研发了具有在车辆段内列车自动追踪功能的车辆段ATS系统。主要从系统结构、可靠性措施、功能原理和工程应用等方面对该系统做出了具体的介绍。  相似文献   
948.
节能列车操纵的思路及方法   总被引:1,自引:0,他引:1  
针对机车司机操纵列车时存在不合理的能源消耗这一问题,从列车运行中各种机械功的组成及转化规律入手,根据列车运行需要及操纵经验,对节能列车操纵的思路及方法进行了分析论述。  相似文献   
949.
论述了现代高速列车维修的新观念和新发展,其中包括高速列车维修的系统工程观点、故障和维修质量的新观念;高速列车维修制度的发展及其维修制度改革;阐明了高速列车维修相关技术的新进展,其中包括高速列车维修性设计、诊断技术、维修信息系统和维修基地。  相似文献   
950.
研究分析高铁动车组长距离降弓惰行的应急方案,通过在高铁整个供电臂内组织动车组降弓惰行通过的试验,结合运行中的实际案例,验证了高铁上实施长距离降弓惰行通过方案的可行性,并提出应急处置时的相关建议。  相似文献   
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