Left-turn gap acceptance models considering pedestrian movement characteristics

• Published in: Accident analysis and prevention 2013-01, Vol.50, p.175-185
• Main Authors: Alhajyaseen, Wael K.M., Asano, Miho, Nakamura, Hideki
• Format: Article
• Language: English
• Subjects: Accident Prevention; Accidents, Traffic - statistics & numerical data; Biological and medical sciences; Conflict analysis; Demand; Environment Design; Gap acceptance; Humans; Intersections; Japan; Level (quantity); Medical sciences; Miscellaneous; Pedestrian safety; Pedestrians; Prevention and actions; Public health. Hygiene; Public health. Hygiene-occupational medicine; Risk Factors; Safety; Traffic engineering; Traffic flow; Turning vehicles; User behavior; Vehicles; Walking - injuries
• ISSN: 0001-4575; 1879-2057
• DOI: 10.1016/j.aap.2012.04.006

► Pedestrian direction of movement significantly affects the left-turn lag/gap acceptance. ► Observed lag/gap acceptance probabilities are modeled using Cumulative Weibull distribution. ► Drivers accept short lags while being conservative about short gaps. ► Drivers accept shorter lags/gaps between near-side pedestrians compared to far side pedestrians. ► Conflicts occur at low pedestrian demand levels are more severe than those at high demand levels. Pedestrian–vehicle conflicts are considered as a common safety problem at signalized intersections. The threat to pedestrian safety is mainly related to the interaction with turning vehicles, especially left-turners (left-hand traffic system). This study aims to analyze the lag/gap acceptance behavior of left-turners considering pedestrian movement at signalized crosswalks. Furthermore, the severity of pedestrian–vehicle conflicts is addressed by analyzing vehicle speeds at the conflict points. User behavior at several signalized intersections in Japan is observed by using video cameras. It is assumed that pedestrian movements have their origin at either the near-side (the side of the exiting vehicular traffic) or far-side of the crosswalk. Accepted/rejected lags and gaps are extracted, classified depending on the direction of pedestrian movement, and modeled by using Cumulative Weibull distribution function. The results show that drivers tend to accept shorter lags/gaps between near-side pedestrians compared to far side pedestrians. Furthermore, drivers tend to accept short lags while being conservative about short gaps. Simultaneously vehicles clear the conflict area with significantly higher speeds when accepting lags with single pedestrians. This indicates that the conflicts that occur at low pedestrian demand levels are more severe compared to those at high demand levels.