Analysis And Research On Rail Transit Safety Modeling Based On Network Model

With the rapid development of China’s rail transit,the rail transit system has raised higher requirements for its safety while improving operational efficiency.Generally,the rail transit system is composed of multiple subsystems,and each part affects and is involved in each other.Failure of any part may cause delays in traffic operations and even accidents.Once an accident occurs,under the condition of rail transit network,it will also affect other lines and even the entire rail transit network.Under this background,it is of great significance to study how to prevent accidents and how to efficiently carry out accident(fault)rescue.In the prevention of railway accidents,the identification of key causes is an important step in the effective monitoring of the daily maintenance of the railway system.It is of great significance to deeply analyze the causes of railway accidents and find out the key causes.Existing key factor identification methods are generally based on importance ranking,but they do not consider the classification of accident-causing factors and lack effective verification methods.Based on the complex network theory,this paper proposes an effective method to identify the key causes of railway accidents,and to prevent them before they happen.In view of the difficulty of accident(fault)rescue after a subway accident,this article establishes an accident analysis model and a train rescue framework,analyzes the impact of a subway accident on train operation and passenger flow,and proposes specific measures to improve rescue efficiency,reduce accident impact,and improve Service Level.The main research contents are as follows:(1)In the analysis of railway accidents,the existing key factor identification methods are generally based on importance ranking but lack the means of effective verification.Based on the complex network,this paper proposes a heterogeneous network model suitable for the classification of accident causative factors to find the key causes of accidents.In the proposed model,the causes of different types of railway accidents are considered separately.The cause of the accident is taken as the node,and the correlation between the causative factors is the edge.The key factors will be determined through the extraction of the key nodes.Also,weighting factors are introduced into the SIS propagation model to further verify the effectiveness of the proposed method.The results show that the key nodes found by the proposed method are more obvious than the existing betweenness centrality and clustering coefficients.The effect of the propagation in the SIS model is more obvious,and the importance of the nodes is higher.And because of the strong network heterogeneity,it is proved that the method is suitable for finding key nodes in heterogeneous networks.(2)An analysis model of subway accidents under a networked environment is established and the algorithm steps are given.The model considers the correlation between the number of trains out of service caused by subway train accidents and the train running speed,train tracking time and line occupancy rate.The case study takes Zhichun Road Station in Beijing Metro Line 10 as an example to study the impact of an accident on subway operation.The calculation results of the model show that the number of trains in suspension increases with the increase of train running speed and line occupancy rate,and decreases with the increase of train tracking time.When an accident occurs on a subway line,as the duration of the accident increases,the passenger congestion at the transfer station increases,and the average delay of the transfer train at the transfer station is 9.2 seconds.(3)For the rescue of subway accidents(faults),this article establishes a train emergency rescue framework,proposes a method for calculating emergency rescue time,and proposes improvements to the existing rescue organization from the aspects of equipment and facilities capabilities,staff business level,rescue process,etc..The analysis of the example is simulated by the design scenario.The results show that the improved rescue organization method shortens the rescue time by at least 95 seconds compared to the original rescue organization method,improves the rescue efficiency,and reduces the interference of rescue work with other trains on the main line.Figure 22,table 10,reference 59.