Performance Evaluation of U-Turn at Median Opening Case Study : Conventional Median Opening With Loon and Without Loon on 4 Lanes Roads.

Abstract

The U-Turn at-grade was considered the problems to improve efficiency and safety. There were 3 reasons consist of (1) Turning Volume, (2) Storage length, and (3) Limited Sight Distance. According to the main problems, type of U-turn found the presence of a turn lane and the presence of loon on 4 lanes. The objective of this research was to analyze the efficiency of the U-Turn and present alternatives for management with traffic simulation models. These research studies found factors in median opening depend on 2 parts. (1) U-Turn geometry, such as storage length, median width and right of way. and (2) The volume opposing through and U-Turn relationship has a capacity of about 1,100-1,200 vehicles per hour. and will decrease as the volume of opposition increases. As for the effect of queue length varying with the capacity of U-Turn.