Research on the Design of an Express Bus Line in a Metro Service Bottleneck Section: A Case Study of Nanjing, China

One of the increasingly serious problems facing public transit is the mismatch between metro service capacity and travel demand. In some sections with large passenger flow, this has created a bottleneck, restricting the development of the metro. This paper studies the bottleneck section of the Nanjing metro service. The following work is mainly done: (1) Proposing a method of using the express bus line to relieve metro passenger demand. (2) Extracting passenger flow from passengers' card-brush data and assigning it to the metro network to obtain bottleneck sections. (3) Establishing an average saturation model to calculate the most suitable number of express bus stations. The results show that the method can effectively reduce the saturation of cross-section passenger flow in the bottleneck section of the metro and improve passenger travel satisfaction on the basis of ensuring the rational use of metro capacity.