Exploring the complex relationship between metro and shared bikes in the built environment: competition, connection, and complementation

Merging the flexibility of bike-sharing systems with the high capacity of metro transit significantly enhances both connectivity and efficiency in urban transportation, promoting eco-friendly travel options and supporting sustainable urban development. Current studies primarily examine how these two transportation modes work together to enhance urban travel efficiency and convenience. However, there is still a lack of discussion on the spatial heterogeneity of the competitive and complementary relationships between two modes across different built environments. This study selects Shenzhen as a case study and employs a data-driven approach to explore the relationships between bike-sharing and the metro system in practical application, including competition, connection, and complementation. The OPGD model is deployed to assess how the built environment influences these dynamics. The results reveal that bike-sharing typically complements the metro system, with longer ride durations occurring mainly in the urban core areas. Conversely, competitive interactions between these two modes are less frequent and associated with shorter rides, typically occurring in locales with a high density of metro stations. Educational, service, and residential factors are the main influences on people's choice of the "bike-sharing + metro" travel mode. The built environment exerts a greater impact on competitive relationships and less on complementary ones.