The synergy impact of private vehicle restrictions and public transportation improvements on commuters: a case study of Chengdu, China

Vehicle restriction policies help alleviate peak-period traffic congestion and reduce environmental pollution in urban areas. However, the inconvenience and crowding of public transportation lead to commuter dissatisfaction, particularly among those transitioning from motorized commuting to public transportation as a result of vehicle restriction policies. Utilizing multisource data on various travel modes in Chengdu, China, the study examines the practical effects of two vehicle restriction policies (one-day-per-week and odd-and-even) within the context of public transportation improvements. The study investigates how commute choices across various travel modes (subways, buses, ride-hailing services, shared bikes, and private cars) influence commuter surplus and the shift from motorized commuting to public transportation. The results indicate that the combination of different vehicle restriction policies and public transportation enhancement strategies has varying effects on commuters’ mode choices. Improvements in bus frequency, regardless of the specific restriction policy they are combined with, lead to a win–win situation. These improvements enhance commuter surplus and promote a shift to public transportation modes within a short timeframe. In contrast, expanding bus routes has a limited effect on both enhancing commuter surplus and alleviating traffic congestion.