Study On Area Traffic Characteristics And Control Strategies Under The Influence Of Large Special Event

Large special events can attract multitudinous traffic flows arrived at a small area of the city during a short time, this phenomenon poses a severe challenge for the urban transportation system which focuses on resolving the conventional traffic problem including commuting, business, going to school and so on. Especially with the development of the economic, some international large-scale events with significant influence are held frequently in our country, which made the resolution of this problem becomes imminently. Traffic status is an important indicator of successful special events. It will be a resolved problem, that how to minimize the impact on daily traffic from the special events and protect the special events carried out smoothly. This thesis focused on the traffic characteristics on road network affected by the large-scale events, the influence of daily traffic and the control and management strategies for special event.Firstly, with the dissipated traffic data of the large-scale events from high digital video monitoring systems, this thesis analyzed traffic characteristics when special events dispersal, pointed out that the audience behaviors during the special events are short-term unconventional travel, which has characteristics different from conventional transport, such as short duration, temporary, inducing great travel demand, all to one mode (all travel production starting points to one destination), distinct difference of traffic travel and so on.Secondly, analyzed traffic space-time evolution rules of the special events disposal, and proposed a space-time dissipation method which considered the spatial distribution and traffic flow distribution. Used VISSIM traffic simulation software to make the network simulation more comprehensive, verified the accuracy of the simulated network, and studied traffic characteristics laws of special events, including traffic flow disposal laws, speed variation laws in different road, time-mileage laws and speed variation laws in the situation of weather organized special events.Ultimately, traffic signal fuzzy association control method was proposed for oversaturated intersection during special events. With the object of improving capacity and avoiding overflow for oversaturated intersections, the methods of how to determine queue length threshold, detect threshold and estimate queue length were put forward, then according to relevance of sections, traffic flow state, sections space constraints and vehicle release demand, the sections were classified and the dynamic phase combination and phase sequence was designed. On the basis of the above work, by identifying key parameters, the control method for oversaturated intersections was studied with gather-disperse theory and fuzzy control, at last, oversaturated intersections traffic signal interconnected control method was put forward. The simulation result showed that the new method can not only restrain oversaturated intersection overflow, but also can reduce vehicles average delay time.