Assessment of pre-timed, actuated and adaptive signal controls for urban transportation networks.

摘要

The majority of all urban network delays, increased fuel costs and fatalities can be attributed to the delays being experienced at signalized intersections on the major arterials. Currently pre-timed and actuated signal control strategies are widely used at many signalized intersections. Adaptive signal control strategies, on the other hand, have not been extensively utilized due to difficulty in determining their benefits. This report investigates and compares the optimization and the consequential benefits that can be achieved through the use of pre-timed, actuated and/or adaptive signal control strategies by carrying out a systematic transportation planning and traffic operational study. Traffic variables such as level of congestion, directional mix, mid block flows, degree of randomness of arrivals and turning movements are examined to determine their impacts on the potential benefits.;The results of this research provide an insight into various parameters of urban transportation planning and traffic operational network. This research has developed a method to estimate Origin-Destination (O-D) matrix and forecast turning movements at the intersections by integrating transportation planning and traffic operational software. It also provides information under what conditions the use of adaptive and/or actuated control will be more efficient than the use of pre-timed control. Additionally, this research provides guidance to municipalities and local authorities towards the application of pre-timed, actuated and adaptive signal controls for optimizing traffic operations on urban road networks.;Key words: Transportation planning, modeling, simulation, optimization, traffic operations.;The verification of macroscopic and microscopic simulation models was first carried out to assess and analyze their use in the planning and operation of urban traffic signal networks. It was found that the EMME/2, TRANSCAD, Synchro, Sim-Traffic and INTEGRATION transportation planning and traffic operation models could be effectively utilized to carry out this simulation and analysis. Secondly, a simulated network of 9 intersections was developed and properly coded to examine and evaluate the optimization and benefits of pertained, actuated and adaptive signal controls. Thirdly, an idealized large urban network of 132 intersections was developed and evaluated to assess the impacts of the control variables. Finally, an identical analysis was carried out for an urban central business district or downtown network consisting of 237 intersections for the City of Brampton, a medium size city in Ontario.