Video analytics is becoming more reliable and available to assess the safety implications of innovative transport projects. The conflict analysis through video analytics was used to evaluate the safety measures at the first signalised intersection arrangement in Queensland where flashing yellow was deployed to protect active road users against turning traffic movements. The civil road infrastructure layout outside the new school in Dutton Park, Brisbane, included the provision of a Cycle Track on Gladstone Road at the signalised intersection. The signal operations on Gladstone Road have been designed to ensure that people cycling have similar green time as motor vehicles travelling in the same direction.
Various safety measures were compared during six data collection periods throughout the signal post commissioning. Test sites of Gladstone Road and T J Doyle Drive intersection were compared to and the nearby almost similar benchmarking intersections of Annerley Road and Gladstone Road and Annerley Road and Catherine Street.
The project considered two road user conflict indicators: Minimum Time-To-Collision (TTC) and Post Encroachment Time (PET). Traffic events with TTC ≤ 3 seconds and PET ≤ 3 seconds were considered critical traffic conflicts in the analysis.
Overall, the two test sites were found to have comparable or lower critical conflict rates than the two control sites during most hours during a typical day, with only a few exceptions.
Also, no evidence was found to suggest that the innovative infrastructure upgrades, including the crossing offsets and flashing yellow signals, resulted in confusion among the road users regarding crossing priority for cyclists at the test sites, and, consequently, rear-end critical conflicts among the left-turning vehicles and their followers.
