Research On Traffic Safety Risk Of Pedestrians Crossing The Street At Urban Signal Intersections

With the rapid development of my country’s economy and the accelerating process of urbanization,the travel needs of urban residents are also increasing.As a place where pedestrians and motor vehicles converge,intersections are prone to traffic jams and accidents,and conflicts are frequent.In the process of traveling,pedestrians do not have any protective devices and are vulnerable to external injuries,belonging to the vulnerable group of traffic participants.Therefore,in order to reduce the potential danger of pedestrians crossing the street,this paper studies the safety of pedestrians crossing the street at the signal-controlled intersection based on the characteristics of pedestrian traffic behavior and the conflict between pedestrians and vehicles.The paper firstly formulates a research plan related to pedestrian traffic safety at intersections and conducts an overall analysis of the research data.Based on the observation video combined with Tracker software,data collection is carried out on pedestrians crossing the street,motor vehicles crossing the street and the road environment,classification of pedestrian crossing forms from the perspective of violations,and statistical analysis of pedestrian crossing violations,pedestrian start delays,and pedestrian pace.The running state,speed change and distribution of right-turning headway of right-turning motor vehicles are analyzed.Secondly,the paper analyzes the mechanism and characteristics of human-vehicle conflict,studies the occurrence rate,conflict point distribution and conflict classification at intersections,and analyzes the three indicators of TTC,DST and PET for judging the severity of humanvehicle conflict.Applicability,a calculation model was established to solve the index value,and based on the fuzzy C clustering method,a conflict severity level classification model was constructed,and the severity of human-vehicle conflict was divided into three categories:general,minor,and serious.Then,from the aspects of model structure,parameter estimation,model testing,marginal effect,etc.,from constructing an ordered Logit model to constructing a generalized ordered Logit model,the paper quantitatively analyzes the influencing factors and degree of influence of the conflict between people and vehicles,and obtains 9 There are significant factors that affect the severity of conflict,and the factors with the greatest impact are: pedestrians committing early violations,whether pedestrians travel together,gender,and whether they are adults.At the same time,the paper calculates the marginal utility of each factor,and obtains the probability of changing the severity of the conflict when the variable changes.Finally,according to the analysis of the influencing factors of pedestrian-vehicle conflict,the paper proposes two safety optimization strategies,the early-opening phase for pedestrians and the special phase for right-turning vehicles,which are verified by simulation.The delay changes and conflict changes of right-turning vehicles and pedestrians before and after the optimization strategy are analyzed and calculated,the calculation method of the early-opening phase duration is determined,and the settings of the pedestrians’ early-opening phase and the right-turning special phase are respectively explored from the perspectives of efficiency and safety.condition.Using VISSIM and SSAM software,the traffic simulation of the intersection is carried out,and the changes of the intersection conflict and delay before and after different safety policy settings are simulated,which proves the feasibility of the traffic safety strategy.