Study On The Characteristics Of Pedestrians At Countdown Pedestrian Signalized Intersections

Urban traffic is always the hot issue which attracts much attention. Pedestrians andvehicles are always the central topics. The number of vehicle increases rapidly along withthe development of the social-economic.As a result, a large number of the road resources ofwalking is occupied by vehicles. It is harder and harder for pedestrians to walk out andtraffic accidents occur frequently, and the study on the traffic security is urgent.First, the characteristics of pedestrian violation at intersection were analyzed. Thepedestrian violation behavior was defined. Moreover, based on the field data, the influenceof sexuality and age on pedestrian violation was discussed. Consequently, the impact ofcountdown pedestrian signal and general signal on violation ratio was also analyzed.The violation behavior was influenced by lots of parameters including the subjectivefactors of pedestrian violation willingness and the objective factors of intersection design,signal timing and headway distribution. In addition, the pedestrian violation behaviorresults in a large number of traffic incidents. Therefore, on basis of characteristics analysis,the Bayesian Decision Theory was applied to develop a violation ratio model. The crossingstatus of pedestrian was partitioned into crossing without delay and with delay. The loss ofpedestrian includes time lose, safety loss and legal loss which are caused by signal andvehicle interference. The delay time is determined by signal timing and arrival time whenpedestrians complywith the law. Meanwhile, the distribution of headway is key factor ofdelay time when pedestrian violates the law. The headway distribution for various turnmovements was depicted by Weibull distribution. The delay time of pedestrian was furthercalculated under different crossing patterns. Subsequently, a typical intersection wasselected to validate the proposed model. The headway model was calibrated and the fieldpedestrian violation data was collected to be the standard value.Based on the validation of proposed model, the method of univariate analysis wastaken to analyze thesensitivity. The parameter of signal timing and number of lanes wasanalyzed. According to the sensitivity analysis, the crucial parameter was identified.Consequently, it is possible to develop some suggestions about intersection optimization fortraffic managers in view of the pedestrian violation ratio.