Research On Dynamic Coordination Control And Optimization Methods Of Arteries Based On Road Traffic State Identification

In recent years, with the development scale of urban expanding and the continuous adjustment of the spatial structure, the trip distance is gradually increasing, the total traffic demand continues to be enlarged, which gradually shows the imbalance between the supply and the demand of traffic temporal resource. Urban traffic congestion presents the situation that the congestion period extends from the peak period to the flat peak period, the congestion scope expands from the locality to the region, the congestion state converts from the sporadic to the normal. So the development of urban transport system is facing with serious challenges, and improving service level and traffic capacity of the network is an important measure to ease urban traffic congestion.Studies have shown that it is not enough only to rely on speeding up the construction of urban roads to manage traffic congestion but need to depend on advanced traffic management and control measures to ease the traffic congestion problems. In this paper, regarding the urban road as the subject and aiming at its traffic scenes and network state, we analyzed the traffic network elements of intersections and links and their mutual mechanism, identified the road traffic state and investigated the strategies easing traffic congestion to propose effective dynamic coordination control and optimization methods of arteries, the achievement of which will provide technical support and theoretical basis for traffic management and control of urban road systems. Research contents are briefly summarized as follows:Firstly, the traffic information collection and characteristic parameters are analyzed. By analyzing the operational principle of vehicle detectors, the layout optimization of loop detectors was proposed. Based on traffic information collection, traffic parameters were studied and the similarity of time dimension and space dimension was analyzed, which provides the basis for the state identification of road traffic.Then, the state identification of road traffic is introduced. Fuzzy comprehensive analytic hierarchy process was applied into analyzing each evaluation index and the mutual mechanism among traffic states including the confirmation of factors set and judgement set, the membership function establishment of each evaluation index and the calculation of its weight, and each evaluation index and the road traffic state are respectively conducted the single factor evaluation and fuzzy comprehensive evaluation to determine the comprehensive index of the road traffic state.Thirdly, road traffic signal control strategies are discussed. Based on the state identification, traffic signal control strategies are in depth studied. By studying the traffic control mechanism of point, line, area, we analyzed the correlation characteristics of each intersection and divided the control sub-area. The control modes were selected according to the operating state of traffic flow and the control strategies were evaluated using the appropriate evaluation index, which revealed synergistic reaction of control strategies.The fourth part describes the dynamic coordination control and optimization methods of arteries. Based on the analysis of road traffic state identification and road traffic signal control strategies, taking dynamic coordination control as the idea, traffic wave theory as the foundation, the cycle, phase, sequence, green ratio, phase offset and other control parameters were optimized, and we raised the dynamic coordination control and optimization methods of arteries with the main line improving road service level and developed the quantitative models.Finally, case studies are presented. Binhai road in Huangdao district is implemented dynamic coordination control and optimization of bidirectional green wave using the TDP green wave software tools and the data are used for mathematical statistical analysis. Through comparing the index values before and after the dynamic coordination control and optimization, the accuracy and practicability of dynamic coordination control and optimization methods are to verified, making further efforts to study the dynamic coordination control and optimization methods of arteries fitting our country.