Effect of Waiting Time on the Gap Acceptance Behavior of U-turning Vehicles at Midblock Median Openings

Abstract

The waiting time at the stop line, one of the factors affecting the gap acceptance behavior, was investigated in this study. The study focused on the u-turn movement of passenger cars at midblock median openings. The statistical analysis was conducted to judge the effect of the waiting time. The analysis results showed that the waiting time of more than 30 seconds would frustrate the drivers to accept the significant smaller gap than the drivers facing smaller waiting time at the 90% confidence interval. The critical gap parameters were also estimated by the classical regression method. The results showed the critical gap of 4.3 seconds and the follow-up time of 3.4 seconds. The capacity models showed the maximum u-turn capacity of 1,060 pcu/hr. The u-turn traffic control and management at median opening was recommended for safety purpose, especially when the u-turning vehicles might face the long waiting time.