Research On Queuing Optimization Model Under Over - Overflow Condition Of Over - Saturation Crossing

With the rapid development of national economy in our country, the car ownership is growing rapidly. But the public road traffic infrastructure construction relative lag, the gap between traffic supply and traffic demand is bigger and bigger. Urban road traffic congestion also from "no" to "have", from "a single spark" to "the potential of fire" is gradually deteriorating. City road is mainly composed of road section and the intersections. Due to the mixed operation of all directions of traffic flow at intersection, there are a lot of the conflict points, distribution points and conflux points, intersection traffic capacity is smaller than the road capacity, intersection oversaturated traffic flow is often happened.Firstly, this paper divided the stretched import lanes traffic running state of dissipation flow rate into under-saturated and underflow, under-saturated and overflow, over-saturated and underflow, over-saturated and overflow four situations, and studied on their traffic flow rate change rule of dissipation flow, under the research background of urban road oversaturated traffic status and broadening-segment queue overflow phenomenon common existence. Then this paper summarized the time resources and space resources of signalized intersection from the perspective of the whole intersection, put forward the inner transformation relationship of time-space resources and established the time-space resources optimization strategy at the signalized intersection. Secondly, this paper studied the concepts and traffic characteristics of broadening-segment oversaturated traffic status and queue overflow phenomenon. At the same time, the formation mechanism and the internal logic relationship was researched based on traffic investigation and analysis of two different stretching-segment setting signal intersections in Kunming city. Then, this paper analyzed the advantages and disadvantages of coil and video detection and established import lanes traffic running state discriminant model based on the multi-source detecting data. And on this basis, this paper put forward queuing time-space resources dynamic programming model based on variable lane for oversaturated queue underflow condition. This model can optimize the allocation of time and space resources in the intersection and divide the traffic pressure based on the analysis of traffic data from the front-end detection equipment. At the same time, this chapter put forward the queuing time-space resources optimization model based on integrated waiting area setting. Finally, this paper selected Kunming Guangfu Road and Changhong Road intersection as the study object, took the saturation of import lane and the dissipate queue length as the evaluation index, simulated and evaluated this model based on the combination of the microscopic simulation software VISSIM and WM-C6.0 video traffic data detection system. Results show that this model can effectively reduce import saturation, optimize the queuing order, shorten the queue length, so as to avoid queue overflow.