@article{ref1,
title="Operational evaluation of U-turns at at-grade signalized diamond interchanges",
journal="Transportation research record",
year="2019",
author="Zhou, Hongmin “Tracy” and Tydlacka, Jonathan and Ding, Liang",
volume="2673",
number="4",
pages="627-639",
abstract="U-turn lanes are commonly provided at at-grade diamond interchanges with frontage roads to reduce delays for U-turning traffic and for the interchange as a whole; however, there are currently many unknowns related to their design, operation, and use. Researchers of this study assessed the existing practice of U-turn implementation by evaluating operations of U-turn lanes at 25 diamond interchanges in Texas through field data collection and simulation analysis. Researchers determined the performance and limitations of U-turn lanes under various geometric and operational conditions, identified and investigated several factors affecting U-turn lane use, and determined the anticipated effectiveness of proposed solutions to U-turn operational issues. This paper provides implementable guidelines for designing and operating U-turn lanes at diamond interchanges. Among the ten countermeasures studied in this paper, closing nearby driveways, adding acceleration lane for U-turn departures, and separating U-turn departures from conflicting traffic using pylons were found to be effective solutions to improve U-turn operations.<p /> <p>Language: en</p>",
language="en",
issn="0361-1981",
doi="10.1177/0361198119840341",
url="http://dx.doi.org/10.1177/0361198119840341"
}