The Research Of Roundabouts Signal Control And Simulation

The roundabouts played an irreplaceable role in urban transport because of its fewconflicts， security and other advantages in the beginning of the20thcentury. However as theautomobile industry developed fast， the car ownership per capita became higher and higher.The common roundabout capacity can not meet the existing traffic demand. In order to protectthe landscape as well as to improve the capacity of the roundabout， the domestic trafficengineers applied the signal control theory to the roundabouts to improve the ring cross-trafficconditions.This paper made a brief introduction to the origin and development of the roundabouts.Illustrates the changes of roundabouts from the beginning on， such as the into ring rules andthe control methods. It also introduced the major research on the roundabouts that the scholarsfocus on， such as the capacity， critical gap， and the signal control method.Secondly， it introduced the graphic design of the roundabouts， contains the designrequirements of the radius of the center island， interwoven length and the width of the ringroad as well as other indications.Thirdly， the paper made a systematic introduction to the roundabouts signal control.The roundabouts control method can be broadly divided into two types， the singlet signalphase control method and the double signal phases control method. The paper introduced theindications determination method and calculate the inter green time by the conflict-method.This paper do the signal research on the four-way roundabouts, and do the analysis bythe VISSIM simulation. Draw the conclusion that the dual phase signal control can improvethe roundabouts operation best; the single phase signal control has not so good changes to theroundabouts which has a large traffic volume...