The impact of a public bicycle-sharing system on urban public transport networks

As a healthy and environment-friendly trip mode, public bicycle-sharing systems, which have so far been built in hundreds of cities around the world, have been developing rapidly recently. The public bicycle-sharing systems, which are usually spatially embedded where original urban bus transport networks are located, comprise the new urban public transport system together with the bus transport networks. Therefore, studying the impact of the public bicycle-sharing systems on the original urban public transport networks is an important research subject. In this study, using the real spatial location data of the public bicycle-sharing systems of Hangzhou and Ningbo in China, we propose a multi-layer coupling spatial network model that considers the geographical information on bus stations, bus routes, and public bicycle stations by studying the urban public transport networks. The spatial network model consists of bus subnets, short-distance bicycle subnets, and short-distance walk subnets which are interdependent rather than independent. We apply the model to study the influence of bicycling between the short-distance bicycle station pairs (SDB) and walking between the short-distance bus station pairs (SDW) on the performance of the urban public transport networks. Results show that SDB and SDW can significantly reduce the average transfer times, the average path length of passengers' trips and the Gini coefficient of an urban public transport network. Therefore, the public bicycle-sharing systems can decrease the average trip time of passengers and increase the efficiency of an urban public transport network, as well as effectively improve the uneven level of traffic flow spatial distribution of an urban public transport network and will be helpful to smoothening the traffic flow and alleviating traffic congestion.