Study Of The Interaction Between Traffic Assignment And Information Control

The deployment of advanced traveler information system needs a new model for the analyzing and designing of road traffic in the city traffic management. The traffic information increasing of driver reduces the uncertainty of his route choice. Traffic information may change the time and space distribution of traffic stream in urban traffic network, thus the traffic throng is alleviated. There exists a basic problem to answer:how to distribute the information and in what extent could the traffic be improved?A traffic assignment and traffic information interaction model is presented. The VIS SUM and VISSIM simulation models are set up according to the real road network of Park City, Utah, US. The traffic assignment and traffic information interaction model is simulated by VISSUM and VISSIM simulation models. The OD matrix is calibrated by the field turning counts. The effects of traffic control, pre-travel information and in-travel online real time information on traffic improvement are studied through microsimulation. Traffic control and Pre-travel information scenarios are tested under fixed-time signal, vehicle actuated signal and adaptive traffic control signal. In-travel online real time information scenarios are tested under adaptive traffic control signal.Tests have shown that the total travel time and total delay decrease after changing the traffic control strategy. Pre-travel information has improved total travel time and total delay under all the traffic control strategies. Under adaptive traffic control signal, the in-travel online real time information has negative feedback effect, and the traffic flows become stable. The information distribution parameters including frequency, delay and proportion of drivers using the information exists a window effect. Within the widows, total travel time decreases more than 10%, and total delay decreases more than 20%. The conclusion is that by carefully selecting the distribution parameters of online real travel time information, the traffic situation of this road network could be improved.