Operational Evaluation of Right Turns Followed by U-turns at Signalized Intersections as an Alternative to Direct Left Turns
Operational Evaluation of Right Turns Followed by U-turns at Signalized Intersections as an Alternative to Direct Left Turns

Author: Jingjing Fan

Publisher:

Published: 2004

Total Pages:

ISBN-13:

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ABSTRACT: Data reduction was conducted after that and several statistic models were developed evaluating total travel time, travel delay of these two movements and the ratio of drivers choice of RTUT versus DLT. As the conclusion, the study found that RTUT followed by U-turn at signalized intersection has longer delay and longer travel time as compared to DLT and the existence of long cycle downstream signal will discourage driver's selection of RTUT. There conclusions are very important in that they provided decision makers with useful information regarding the selection of the suitable U-turn location.

Determination of the Offset Distance Between Driveway Exits and Downstream U-turn Locations for Vehicles Making Right Turns Followed by U-turns
Determination of the Offset Distance Between Driveway Exits and Downstream U-turn Locations for Vehicles Making Right Turns Followed by U-turns

Author: Jian John Lu

Publisher:

Published: 2005

Total Pages: 194

ISBN-13:

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Florida increasingly uses restrictive medians and directional median openings on multi-lane highways to manage left turn egress maneuvers from driveways and side streets. By installing non-traversable medians and replacing full median openings with directional median openings at various locations, Florida prohibits direct left-turn exits onto some major arterials. The purpose of this research was to evaluate how the offset distance between driveway exits and downstream median openings or signalized intersections impacts traffic operational and safety performance. The primary objective is to determine optimum offset distances to facilitate driver use of Right Turn Followed by a U-Turn (RTUT) maneuvers, specifically investigating (1) traffic operational performance, based on the evaluation of vehicle travel time at various offset distances, and (2) safety performance, based on the evaluation of traffic conflicts and crash data. The focus of this research was on urban or suburban multi-lane divided arterials. Researchers studied the impacts of offset distance under four different scenarios: 4-lane divided roadways accommodating U-turns at median openings, 4-lane divided roadways accommodating U-turns at signalized intersections, 6 or more-lane divided roadways accommodating U-turns at median openings, and 6 or more-lane divided roadways accommodating U-turns at signalized intersections.