Research On Traffic Flow Evolution Model For Large-Scale Activities

With the development of social economic and the improvement of people’s living standard, the holding times of large-scale activities in city gradually have increased. The characters, such as traffic strongly accumulated and dispersed, short-time and unbalanced-distribution of large-scale activities, make traffic demands highly concentrated during the key periods. Under the situation, the high traffic flow brings huge pressure to traffic system especially in bottleneck road. In addition, that may not only increase travelers’ costs, safety hazard, but also aggravate environmental pollution and energy consumption. However, most studies on urban traffic system now focus on solving daily traffic behavior such as commuting, going to school. So The characteristics of traffic flow during large-scale activities are explored, and travelers’departure time and route choice effecting on travel costs in different cases are studied as well. Those can provide theoretical foundation for traffic management department when setting traffic organization schemes scientifically and detailed during large-scale activities. The main job of this thesis are as follows.First, types of large-scale activities are introduced and select the most common type as the research object in this thesis. The characteristics of these types are having fixed start time and end time, having fixed place, having certain number of maximum capacity with fixed seats and the number of activity participants unchanged basically. We analyze the traffic demand characteristics and traffic flow characteristics of this kind of large-scale activities.Second, a day-to-day evolution model was proposed based on no toll based onthe certain User Equilibrium theory. This model can describe the adjustment process of the path flow during peak periods and how the adjustment process influence on the travel cost. We illustrate the mode by a numerical example, and the result shows that the stationary sate of the model is corresponding to the user equilibrium state.Third, toll can alleviate traffic jams effectively as one of demand management methods. So a day-to-day evolution model is proposed in the case of toll. This thesis studied how travelers adjust the travel time when carrying toll during peak intervals of large-scale activities. Moreover, we compare the case of toll with the case of no toll to analyze congestion toll influence on the total cost of the system.Fourth, a day-to-day evolution model was built containing multiple bottlenecks on urban transportation networks with multiple origin and single destination. The urban network is based on the two former models. We combine the approach of the space time expanded network (STEN) to analysis and study how travelers adjust the travel time and routes during peak periods of large-scale activities on urban transportation networks with multiple origin and single destination and how the adjustment process influence on the system total cost.