A Study On Turn Around Capacity And Evaluation Of Track Layout In Terminal Stations

Terminal stations, as key points in the metro network, play an important role in the operation of urban railway transportation. It has a great influence on the operation efficiency and performance of the overall network. A well-designed terminal station is supposed to provide safe and efficient turnaround route for the vehicle. Otherwise, an improper design will cause a severe loss of capacity. As a complex system, all sub-systems can have an impact on the turnaround capacity. The classical evaluation method can only be used to evaluate the goodness of stations which have been put into operation. At present, loads of research has been conducted on the qualitative analysis of track layouts, while a small amount of research has been done on the quantitative analysis of track layouts with lots of work which involves a lot of mathematical models. This type of research is only valid in the evaluation of single scenario and the operation cost of the station is not taken into account in the analysis. As a result, a study on the evaluation of track layouts is very necessary.During the research, a new evaluation system is studied based on literature review and site visit to the metro depot. Through conducting analysis of different impacts which different factors have on the track layout, an evaluation system is established. By combining the theoretical calculation and practical data, a qualitative analysis is conducted to provide an integrated evaluation in order to give an overall analysis of the network performance.The major activities carried out in this dissertation were:(1) By illustrating general principles in track layout design, the key factors in the evaluation are determined. From the angle of Railway System Engineering, different factors which have an impact on turnaround capacity are studied individually. Then an evaluation system which can be used in the practical scenarios comparison is described in details.(2) With the assistance of software RSAT (Rail Simulation Analysis Tool) which is developed by a PhD student, David Kirkwood from University of Birmingham, a series of modelling and theoretical calculation have been done in order to determine the turnaround capacity in five different track layouts. (3) The author summarized and worked out the initial cost and the operation cost in different track layouts over the ten years. Based on the classical NPV theory, all the costs were transferred to discounted costs over a ten year period for each track layout and all costs were added together to give an overall monetary value which can be compared among the different layouts.(4) By doing calculation of turnaround capacity and economic indexes, a series results were worked out. The results enabled a comparison of NPV (Net Present Value) of the five layouts under different conditions by altering different variables, e.g. timetable interval. The evaluation system is approved to be validated and practical.