Exploration of the Beltway Toll-free Policy With the River-crossing Needs
Aiming at the increasingly serious river-crossing traffic congestions and under-utilizations of beltways in many cities,Changsha was taken as the example to explore the impact of beltway toll-free on the river-crossing traffic.Firstly,traffic operations of all urban crossing Xiangjiang River channels in Changsha were investigated.It is found that Houzishi Bridge and Xiangfulu Birdge had severe traffic congestions at morning and evening peaks.The traffic flow data was analyzed and modeled by Greenberg model to build the traffic flow model.Then,according to the expressway frame data,based on the evening peak beltway ETC data,it is found that 67.2%of the Changsha Beltway traffic travelled was inside the city,only 0.8%of them was city-crossing traffic and mainly minibuses,which lays better foundation for the toll-free policy.Analyses of the morning peak traffic have similar findings.Finally,if in the toll-free policy of the beltway,5%,10%,and 15%of traffic of Houzishi Bridge and Xiangfulu Bridge were diverted to the beltway,it is found that traffic congestions of these two bridges can be greatly alleviated with keeping the beltway traffic smooth.