Loughborough University
Browse
1-s2.0-S0001457523003883-main.pdf (8.41 MB)

Before-after safety evaluation of part-time protected right-turn signals: an extreme value theory approach by applying artificial intelligence-based video analytics

Download (8.41 MB)
journal contribution
posted on 2024-02-01, 11:02 authored by Md Mohasin Howlader, Yasir AliYasir Ali, Andrew Burbridge, Md Mazharul Haque
Extreme value theory models have opened doors for before-after safety evaluation of engineering treatments using traffic conflict techniques. Recent advancements in automated conflict extraction technologies have further expedited conflict-based safety evaluation as a potential alternative to traditional crash-based methods. However, the suitability of extreme value theory models in the before-after evaluation of engineering treatments needs to be rigorously tested. As such, this study proposes a traffic conflict-based before-after evaluation of a novel part-time protected right-turn signal strategy for right-turn or opposing-through crashes at signalised intersections. A part-time protected right-turn signal strategy refers to a signal arrangement where permissive and fully protected right-turn phasings are operated during peak and off-peak hours, respectively. A deep neural network-based computer vision technique was applied to extract the conflicts from a total of 654 h of video recordings (before period: 266 h and after period: 388 h) over seven treated approaches, and four matching control approaches at five signalised intersections in the city of Cairns, Australia. Using post encroachment time and post-collision velocity difference as traffic conflict measures, non-stationary bivariate generalised extreme value models were developed to estimate the severe and non-severe opposing-through crashes at signal cycle levels. The odds ratio analysis of model-predicted crash risks suggests that part-time protected right-turn signals reduce 67% and 81% of severe and non-severe opposing-through crashes at signalised intersections, respectively. Part-time protected right-turn signal strategy offers a good safety solution without precipitating need for capacity upgrades to accommodate queued right turners at signalised intersections.

Funding

Australian Research Council grant LP220100226

History

School

  • Architecture, Building and Civil Engineering

Published in

Accident Analysis & Prevention

Volume

194

Publisher

Elsevier

Version

  • VoR (Version of Record)

Rights holder

© The Author(s)

Publisher statement

This is an Open Access Article. It is published by Elsevier under the Creative Commons Attribution-NonCommercial 4.0 International Licence (CC BY-NC). Full details of this licence are available at: https://creativecommons.org/licenses/by-nc/4.0/

Acceptance date

2023-10-08

Publication date

2023-10-19

Copyright date

2023

ISSN

0001-4575

eISSN

1879-2057

Language

  • en

Depositor

Dr Yasir Ali. Deposit date: 30 January 2024

Article number

107341