@article{ref1,
title="Impacts of changing from permissive/protected left-turn to protected-only phasing: case study in the city of tucson, arizona",
journal="Transportation research record",
year="2019",
author="Li, Xiaofeng and Weber, Alexander and Cottam, Adrian and Wu, Yao-Jan",
volume="2673",
number="4",
pages="616-626",
abstract="Recent research has focused on the safety or mobility impacts of signal timing. Several studies have compared the choice between a protected-only left turn (PO) and a protected-permissive left turn (PPLT). However, few have compared both the safety and mobility impacts, and their tradeoffs. This study proposed data-driven methods to conduct a pilot study at an intersection in Tucson, Arizona. This study evaluated the impacts on vehicular mobility and multi-modal safety when changing from a PPLT to a PO. First, the daily and annual delay for the through and left-turn movements for the intersection was evaluated using a calibrated delay model and year-long 15-min traffic sensor data. Then, real-world near misses between cyclists, pedestrians, and vehicles were manually collected and analyzed using 48 h of videos. Last, both mobility and safety measures were converted into an annual cost to determine the trade-off between the before (PPLT) and the after (PO) situations. The results of this study demonstrate the feasibility of the proposed methods, providing practitioners with different options to evaluate left-turn phasing strategies effectively and efficiently.<p /> <p>Language: en</p>",
language="en",
issn="0361-1981",
doi="10.1177/0361198119842108",
url="http://dx.doi.org/10.1177/0361198119842108"
}