The Research On The Traffic Conflict Between Right-Turn Motor Vehicles And Non-Motor Vehicles At-Grade Urban Intersection

The grade urban intersection gathers the mixed traffic flow composed of motor vehicles,non motor vehicles and pedestrians,which is a relatively weak area of traffic safety.At intersections,right-turning motor vehicles are usually not constrained by signal control and are prone to traffic conflicts with non-motor vehicles.When a traffic conflict develops to a certain extent,it may evolve into a traffic accident.Therefore,in order to improve the safety of intersections,it is necessary to study the traffic conflict between right-turning motor vehicles and non-motor vehicles.Based on the field survey data and using the traffic conflict technology,this paper analyzes the severity and influencing factors of the traffic conflict between right-turning motor vehicles and non-motor vehicles at the intersection,and evaluates the safety status of the intersection.1.Analyze the traffic characteristics and conflict characteristics of right-turning motor vehicles and non-motor vehicles at intersections,select a typical intersection,adopt video survey method,and use drones to take videos of the intersection from above.Based on the shooting video,the Tracker software was used to extract the trajectory data of the traffic conflict between right-turning motor vehicles and non-motor vehicles,and the mean filtering algorithm was used to smooth the trajectory data,and the traffic characteristics and conflict characteristics laws presented in the conflict process were summarized.2.Based on the time difference to collision(TDTC),the probability of time difference to collision(PTDTC)is proposed.PTDTC and deceleration to safety time(DST)are selected as the index to quantify the severity of the traffic conflict between right-turning motor vehicles and non-motor vehicles,and a corresponding calculation model is established to solve the index value of each sample.The severity of sample conflict is divided into three categories:minor conflict,general conflict and serious conflict by FCM clustering method.3.Using the ordinal logistic regression analysis method,the influencing factors of the traffic conflict severity between right-turning motor vehicles and non-motor vehicles are analyzed and modeled.It is concluded that the flow of right turning vehicles,the change of speed of right turning vehicles,the following situation,the flow of non motor vehicles,the change of speed of non motor vehicles,the situation of non motor vehicles running red lights,the situation of non motor vehicles passing through,and the width of right turning lanes are the significant influencing factors.4.Taking the 8 traffic conflict areas of the intersection as the sample objects,using the total traffic conflict rate and the serious traffic conflict rate as the analysis indicators,the grey clustering method is used to establish the safety evaluation model of the right-turn motor vehicle and non-motor vehicle traffic conflict area at the intersection.Determine the safety level of each traffic conflict area,verify the effectiveness of the model based on the actual situation,and propose improvement measures.