Reasearch On Traffic Conflicts And Safety Evaluation Between Pedestrian And Right-turning Vehicle In Signalized Intersection

Aiming at pedestrian safety at urban signalized intersection, this thesisinvestigates potential crashes by between pedestrians and vehicles by applyingtraffic conflict techniques. First, the paper presents a comprehensive literaturereview on studies concerning traffic conflicts between pedestrians and vehiclesand summarizes the latest research results in China and elsewhere in the world,which includes critical traffic conflict analysis methods, data collectiontechnology, evaluation of potential consequence of conflict and practicalapplications.The scope of the study is on conflict between vehicle right turn andpedestrian. Specifically, the thesis investigate right turn flow characteristics atsignalized intersection and their conflicting with crossing street pedestrian.The extensive video data were collected and SIMI Motion software was used toretrieve the data that reflect right-turning vehicle conflicting elements such asdistance traveled, operating speed, acceleration. And deceleration. By analyzingthe retrieved data, the study is able to identify characteristics of conflictingpedestrian and vehicle flow. With deceleration rate as the judging criteria, thethreshold were developed based on right-turn vehicle deceleration change fornon-conflicting vehicle maneuvers, which allows the investigation only keepingthe data when the conflict occurred. Through analyzing the refined traffic data,the study reveals how traffic volumes of both vehicular and pedestrian affectthe number of conflicts, which served as the basis for a conflict evaluationmodel. With the developed model, this study evaluates the four conflict pointswith Morning, flat and evening peak by the gray cluster theory using the ratio ofconflicting vehicles over total traffic volume as evaluation index. The model isvalidated by the case study results that also demonstrates the modelapplicability.