Research on the Influence of Last Digit Restriction to the Traffic Flow Characteristics

The Beijing government is taking measures to remit traffic congestions by restriction based on the last digit on a license plate, which influences the characteristic of traffic flow. This paper first builds a model about traffic flow characteristic, including vehicle velocity, roadway reliability and traffic congestion recovery time. The paper also researches different pattern of vehicle velocity before and after the rail number restriction, analyzes the changing trend of road-mobility reliability with traffic demands, and calculates the pattern of traffic congestion recovery time between the restrictions. The result indicates that when traffic flow’s density is large, the vehicle’s velocity is increased to 180% of the original after the restriction; and the recovery time from congestion to smooth is decreased to 75.8% of the original; after taken the restriction measures, the road unblocked reliability in Peak hours is increased, and the traffic condition ameliorate evidently.