Study On Signal Timing Parameters Based On Conflict Analysis At Roundabout

Roundabout plays a significant role in the operation of urban transport in the early20th century because of conflict points less and the safe passage of vehicles, etc., but withthe rapid increasing of the car ownership, the capacity of the existing roundabouts hasbeen unable to meet the needs of traffic, in order to meet demand of urban traffic needand improve urban transport capacity Roundabout, domestic scholars proposed signalcontrol method for roundabout. Paper is organized as follows:To the unique of the geometry and traffic flow characteristics of roundabout, thepaper study on the traffic flow characteristics and signal timing. Based on the summary ofthe existing roundabout insufficient and research on conflict analysis, roundabout trafficflow analysis as a starting point, signal timing method roundabout were studiedmainly.Paper is organized as follow:The paper overview and summary the research status of the Roundabout from trafficflow characteristics, capacity, control method, and so on, and finally presents the mainresearch content and methods course.The paper analysis the characteristics of the vehicle reaches, speed characteristics andheadway characteristics base on the measured data, established the mixture distributionmodel based on the negative exponential distribution and normal distribution, verified theeffectiveness of the model using field data; this played a foundation for subsequentresearch by analyzing the traffic flow characteristicThe third chapter on the basis of traffic conflict analysis, according to the roundaboutgeometry and flow conditions, proposed roundabout phase setting method: with fourintersection roundabout that has two phase as analysis object,analyze the conflict betweenphase and phase internal traffic conflict to determine the calculations of roundaboutgreen interval time; For the condition of the capacity constraints in different regions, withfour intersection roundabout that has two phase as analysis object, analysis thecharacteristics of the key conflict point, established the cycle time model.The forth chapter using traffic simulation software VISSIM simulation of the actualroundabouts, basing on traffic data by field survey, using the relevant parameterscalculation method, get the signal time of the roundabout, with the delay as indicators toprove the timing parameter calculation is correct. The fifth chapter of the paper,the main findings were summarized and presented tothe next research program.