Research On The Method Of Station Capacity Assessment Of CBTC Superposed On CTCS-2

Under the guideline of building a strong country in transportation,suburban trains are planed to insert in existing high-speed railways in Hainan East Ring Line.A technical scheme of CBTC superposed on CTCS-2 is proposed.The effect of capacity improvement in CBTC superposed on CTCS-2 becomes one of the important references for the feasibility of the technical scheme.The current capacity assessment methods used in the CBTC standard cannot be simply copied and applied to high-speed railways.The operating characteristics of mixed signaling system in high-speed line need to be considered,especially turnback operation in high-speed line is a new problem.Therefore,it is necessary to reseach a capacity assessment method of CBTC superposed on CTCS-2 in high-speed railway,especially station capacity which is usually the bottleneck of the whole line.The method of station capacity assessment based on blocking time and operational planning period in CBTC superposed on CTCS-2 is proposed.First of all,Colon-Graph topology is used to model the line infrastructure.A dynamic model of train and ATP model for high-speed railway trains and urban rail transit trains are established.Considering the workflow of CTCS-2 and CBTC signaling system and the requirements of operation,the relevant database is established.Quantitative assessment and calculation are guaranteed by scientific and accurate data provided by above models and database.Secondly,the method of station capacity assessment based on blocking time and operational planning period is proposed,which fits different types of stations.Detail points are as follows:(1)The definition and the principle of section division is proposed.The blocking time models of different section types in CTCS-2 and CBTC are established,as well as blocking time models of different operation scenarios in CBTC superposed on CTCS-2 are also established.(2)The method of confirming operation planning period is proposed,include non-turnback operation station and turnback operation station: An algorithm of combining with the occupation scheme of station and the operation ratio is constructed to determine the operation planning period in non-turnback operation station.the operation planning period is determined by graphic method considering turnback strategy and the operation ratio in turnback operation station.(3)The Heap Mode and the Max-plus Automata model are introduced to establish capacity calculation model.(4)Conflict detection and adjustment algorithm: Considering the possible conflicts of time limit conditions that cannot be detected by blocking time,the conflict detection and adjustment algorithm is established.Finally,taking Hainan East Ring Line as a case,the method of different kinds of station capacity assessment is applied to typical stations,which verified the feasibility and validity of the method.The results show that the capacity of Hainan East Ring Line is improved obviously in CBTC superposed on CTCS-2.According to quantitative assessment,we can choose different turnback strategy in turnback station.Contrasting with the opration datas,the results of capacity assessment in CTCS-2 is in accordance with real datas.In summary,the method of station capacity assessment based on blocking time and operational planning period can be used in different types of stations,and station capacity can be evaluated scientifically and accurately.Using this method,the bottleneck section in station area and time margin in each section can be shown directly.This method will provide data foundation for the following integrated section-station capacity assessment.