Signal Control Optimization Research For The Exclusive Pedestrian Phase Intersection

Pedestrians are usually in a disadvantaged position in traffic accidents.The intersection of urban roads is a place where motor vehicles and non-motor vehicles have conflicts thought to be one of the high incidences of traffic accidents.Exclusive pedestrian phase is a signal phase that gives pedestrians independent access rights.During the exclusive pedestrian phase all motor vehicles are prohibited from passing,stripping the conflicts between pedestrians and motor vehicles,significantly improving the safety of pedestrians crossing the street.As a result,exclusive pedestrian phase is becoming popular in more and more cities,but there is no uniform standard for exclusive pedestrian phase signal timing schemes and setting conditions.Therefore,it is of great significance to carry out research on exclusive pedestrian phase signal timing and setting conditions.In this paper,firstly the speed characteristics and waiting time characteristics of pedestrian crossings at signalized intersections are obtained through investigations.The forms,causes and current solutions of the pedestrian-vehicle conflicts are analyzed.Secondly,based on the summary and analysis of traditional signal timing methods,bilevel optimization model is proposed,which comprehensively considers pedestrian and motor vehicle benefits.and the model is solved.Thirdly,the actual exclusive pedestrian phase intersection is selected as a case study,and the effectiveness of the bilevel optimization model is verified by Vissim simulation.Finally,on the basis of the case,a common signal phase timing scheme is obtained by using Webster method,and then the Vissim model is used to model the intersection.By changing the traffic parameters of the common phase intersection model and the exclusive pedestrian phase intersection model,the output indices of the two models are analyzed,and the traffic conditions of exclusive pedestrian phase setting are obtained.The results show that the bilevel optimization model has good applicability for exclusive pedestrian phase timing optimization;exclusive pedestrian phase is suitable for planar signalized intersections with high demand for pedestrian crossing and vehicle saturation greater than 0.6.When the demand for pedestrian diagonal crossing is higher than 60% and the turning rate of motor vehicle is higher than 50%,the effect of setting Exclusive pedestrian phase is the best.