| Over the past two decades,China has entered a very rapid urbanization process,expanding at an alarming rate to complete it.In the process of urbanization,we have enjoyed the dividend of China’s economic take-off and the improvement and optimization of urban infrastructure and transportation system.The urban road network is criss-crossing,which greatly improves the convenience and accessibility of our daily travel.But we also facing some disadvantage results which urban transportation development had brought and the demographic dividend brought by the serious traffic congestion problems,our city like a great pie,in the behind of this city development model,our city planning with the development of car-oriented,which led to our urban road resources is in short supply,we urgently need to optimize the urban road traffic organization design,improve our road and intersection space-time utilization.This paper summarizes the four non-traditional traffic organization optimization design schemes,such as the design method of CLL(Contraflow left-turn lane),the"Tandem" organization optimization design method and the pre-signal design application of the bus priority strategy and EFT(Exit-lanes for left-turn)exit type-left turn traffic mode.This paper proposes a new method of traffic organization optimization based on the adaptive control of the main and pre-signal,and proposes a variety of control strategies and dynamic selection of different strategies based on real-time traffic conditions.The traffic algorithm of the first layer is designed,and the second layer control of adaptive algorithm with different strategies and real-time switching is given.Considering the temporal and spatial dynamic changes of traffic flow characteristics,a strategy control method is proposed to optimize the running state of the current road by means of the technology of vehicle detection and the ITS technology.The geometric conditions,traffic conditions,parameter conditions and facility conditions of the strategy control method are summarized.The critical evaluation index of the control algorithm is put forward:per capita delay.Then,through the VISSIM example,the applicability of the simulation strategy is obtained and the evaluation indexes are analyzed.When the traffic flow is larger,the comprehensive waiting-area optimal design of the traffic organization can greatly improve its traffic capacity and significantly reduce the per capita delay.When the bus departure frequency is higher and the bus and car passenger load factor ratio is greater,set the bus priority traffic organization method to improve the road capacity,reducing the per capita delay has significantly changed.Finally,the paper summarizes the main research results and future prospects of this direction and further study of the paper. |
