| Private car license,as an important control device of urban traffic management for many mega-cities,is the core combination of urban traffic management with corresponding restriction policies.Based on the theory of "externality" in public management and the actual situation of Shanghai,this paper studies the restraining effect of the policy of "license limit" and "administrative limit" on Externality in the management of super-large urban traffic.This paper takes the implementation process of Shanghai’s "Limited License and Restricted Travel" policy as a case to conduct an empirical study.It studies the hedging effect of "Limited License and Restricted Travel" policy on driving externalities in this case by integrating various sociological research methods such as historical data,relevant interviews,literature analysis and comparative analysis of similar cities.Since 1994,license plate auction in Shanghai has undergone from "no bottom price,public auction" to "warning price auction".The core purpose of the policy is to control the number of private cars in Shanghai by controlling the number of license plates put in,and to offset the externality of urban traffic by setting access threshold.Although the implementation of 25 years has controlled the growth rate of Shanghai vehicles to a certain extent,it has won a certain amount of time and construction costs for the construction of urban road network.However,with the rapid development of Shanghai’s dual-center construction,the integration of the Yangtze River Delta has brought huge cross-regional traffic demand,and the current policy deviates from the demand of urban development.In the process of implementing the policy,many fine-tuning has been made for the mode of license plate auction and the time limit period.With the gradual increase of the total number of license plate,the habitual congestion of the peak,north-south elevation,Yan’an road elevation and some sections of the inner ring can not be solved by the restriction of the external license plate.The price of license plate is increasing year by year,and the scarcity caused by restrictions on the release of license plate causes market failure,which can not be adjusted by price means.The externalities of urban traffic are generated by vehicles on the road.The root cause of externality is driving rather than driving.According to the specific situation of Shanghai,congested areas are relatively fixed in a certain period of time,mainly concentrated in high-density commercial areas within the outer ring and around large-scale public facilities,driving the same mileage,because the externalities of different origins and destinations are different;like other comparative cities,the traffic congestion time in Shanghai is also bimodal,that is,traffic congestion time is bimodal.In the morning and evening,the externalities of driving behavior in different periods are also different.The externality of urban traffic has the characteristics of short duration,point-to-point,distributed and partially random.In view of the above characteristics and the empirical analysis of the implementation effect of Shanghai’s "Limited Licensing and Restricted Travel" policy for many years,this paper proposes that the focus of governance at this stage should be changed from "double restrictions" dominated by administration to "congestion areas" and "parking areas".The traffic congestion fee levied by different levels of vehicles enables the market to play a leading role in hedging the externalities of driving in urban traffic.It is worth noting that this paper combines the theoretical study of congestion tax(congestion fee)with the actual situation of collection in London and Tokyo.Considering the actual characteristics of traffic management in Shanghai,it innovatively classifies the collection object of congestion fee as non-transit vehicles in congestion areas,which produces greater externality.In addition,the location of congestion tax collection is set at the exit of parking lot.Firstly,the toll station itself is the bottleneck of congestion in the process of collecting a single entry fee in London and other cities.In addition,the implementation cost of congestion surcharge is lower and the policy is more enforceable in the phase of parking fee collection.At the same time,referring to CAR POOL LINE,which has successful experience in North America,it is suggested that carpooling lanes should be set up in some sections of Shanghai Central and Outer Ring,such as Jiamin Elevated Road,Yan’an Elevated Road and North-South Elevated Road to encourage carpooling.At the same time,in view of the current development of domestic shared economy,legal carpooling is encouraged in road use.Under the condition that the total travel demand remains unchanged,policies should be adopted to encourage reducing the vacancy rate of vehicles on the road and reducing the number of vehicles on the road. |