A Study on Capacity Estimation of Shared Left Turn Flow at Signalized Intersection

The objectives of this study are to analyse bay lane capacity and to develope its estimation model. Capacity analysis was carried out In the form of traffic characteristics investigation for the shared left turn flow including U-turn movement at signalized intersection. Capacity estimation model has also been developed for left turn flow with the variation of U-turn vehicle percentage. The summary of this study is as below; 1) The percentage of U-turn vehicle on the lane and the left turn signal time are shown to be most influential variables fir left turn capacity including U-turn movement. 2) The critical percentages of U-turn vehicle causing the lane capacity decrease are found to be more than 25% for 60 m bay lane and more than 20% far 80m bay lane.