How Rail Transit Access Mode Affects Airport Landside Traffic Sharing Rate: Evidence from Beijing, China

Rail transit airport lines, as fast passages connecting urban areas and airports, play an important role in facilitating residents’ travel and optimizing urban spatial layout. This study aims to explore the passenger flow characteristics of airport landside modes under three kinds of rail transit access form: dedicated, general, and mixed. On the basis of analyzing the access features of different airport lines, a three-level nested logit (TLNL) model is proposed to explore the decision-making mechanism of passengers’ landside mode choice in two stages. Then, taking the rail transit of Beijing Daxing International Airport as an example, scenario application is carried out to discuss the change of the landside mode sharing rate after the airport line is extended. The results show that the access form of rail transit has no essential impact on the landside traffic structure. When the airport line extends to the urban area, its sharing rate increases significantly, the passenger attraction effect of the dedicated line being significantly better than the other two forms. Extending the airport line downtown and connecting with large transport hubs can reduce the number of transfers, effectively managing the contradiction between passengers’ travel convenience and comfort. In general, the TLNL model has good applicability to the analysis of how rail transit affects the sharing rate of landside modes; the results can provide reference and ideas for the selection and planning of rail airport line access forms.