Quasi-dynamic Traffic Assignment Method Based on Traffic Control Strategy under Freeway Net

Due to the static traffic assignment not describing the dynamic traffic flow of network, and as the intelligent traffic developing, dynamic traffic assignment becomes research hotspot. Traffic control strategy will influence the driver´s route choices, so these effects should reflect in the dynamic traffic assignment. Freeway traffic bottleneck section or accident often forms different degree of congestion, according to the different congestion degree and the feedback traffic operation parameters of road traffic detectors, different traffic control strategy is needed, such as ramp control, variable information sign, traffic radio and speed limit, etc.. The traffic control strategy will influence the road impedance, which is one of important constraint conditions in dynamic traffic assignment. It establishes a travel cost function considering these factors; and quasi-dynamic traffic assignment model based on the travel cost function is presented. Then, it analyzes the validity and practicability of the model through computer software results.