The spatial efficiency evaluation and classification of multi-modal passenger transportation hubs: A case study in Beijing-Tianjin-Hebei urban agglomeration, China

The spatial efficiency evaluation of multi-modal passenger transportation hubs (MPTHs) in urban agglomeration is conducive to the optimization of future hub layout and urban development enhancement. This study delves into the spatial efficiency of MPTHs by considering three dimensions: intercity travel network characteristics, urban development features, and the connectivity between MPTHs and urban facilities. An evaluation index system consisting of 22 indicators was constructed for MPTHs within urban agglomerations. Gaussian Mixture Clustering was employed to conduct a detailed classification of the development of these MPTHs. A ‘Node-Place-Connectivity’ coupling coordination model was proposed to assess the spatial efficiency of them. Using the Beijing-Tianjin-Hebei urban agglomeration as a case study, the spatial efficiency variations among MPTHs were examined. The results indicated that the efficiency of MPTHs and the coupling coordination degree are divided into 12 classes. Highly balanced MPTHs were concentrated in Beijing, showcasing a monocentric regional structure within the urban agglomeration. Good coordinated MPTHs were strategically located in the main urban areas of cities such as Tianjin, Shijiazhuang, and Baoding, potentially fostering a polycentric urban structure within the urban agglomeration. The coordination and balance of MPTHs gradually decreased from the main urban areas to the periphery, forming a distinct concentric distribution pattern, which was particularly evident in cities like Beijing, Tianjin, and Shijiazhuang. In the marginal areas of cities and urban agglomerations, the efficiency of MPTHs was relatively low, and these MPTHs should be further developed to promote the fairness of socio-economic development in urban agglomerations. This method can serve as a decision-making tool for the planning of MPTHs.