Association of Signal-Controlled Method at Roundabout and Delay

摘要

The uncontrolled roundabout is only applicableto smaller vehicle flows. With increasing of roundaboutflows, series of problems have occurred in respect of trafficjams and accidents. Arrangement of signal control will helpto improve delay and safety at roundabout while differencesexist between condition of adaptability and traffic efficiencyunder different signal controlling methods. It is on the basisof “The Secondary Control Theory on Left-turn at CircularRoad” that this text is aimed at mainly introducing the threedifferent control methods of “Control of Orderly DischargeClockwise at Single Entrance Lanes”, “Control of OrderlyDischarge Clockwise at Single Entrance Lanes +Sub-trafficFlow Interweaving”, and “Control of Synergistic Dischargeat Multi Entrance Lanes”. Everything is done inconsideration of roundabout with different amount ofentrance lanes and based on the control theory of trafficsignal and the optimization method. In this foundation, byapplying methods of numeric calculation and experimentaltraffic engineering, we analyze the influence law on theaverage delay of vehicles caused by the signal cycle of timespacestrategic parameters and radius of central island. Theresearch result will help to improve the theoretical systemconcerning signal-controlled circus road and will alsoprovide technical support to the reconstruction ofuncontrolled circus road and to the mode selection of signalcontrol for circus road, which is of important applicationvalue in practice.