Glare on tunnel endpoints: Road safety problem, new methodological approach for analyses and simulations

According to an Austroads research report, one of the factors contributing to the occurrence and severity of crashes adjacent to and within tunnels, is the variation in light levels when entering and exiting tunnel. The variations in light levels cause large visual load on the driver (i.e. a large eye pupil adjustment) when approaching the tunnel endpoints. Nevertheless, the negative effect of glare will not only affect human drivers, but also can be problematic for Autonomous Vehicles (AVs) causing a sudden disengagement of autonomous systems in a critical driving moment.

In this project we proposed a methodology to minimise the variations in lighting that occurs over a short distance at the entrance and exit of the tunnels which increase crash risk. A case study in Brisbane, Australia was selected where significant contrast exists between the dark interior of the tunnel and the bright illuminated environment outside. We tested the use of dynamic solar reflectors to reduce the luminance contrast found at tunnel endpoints, and adjusted luminance levels in accordance with the visual adaptation rate. This study aimed to optimise the location and configurations of these reflectors to fade the sharp transition between the maximum and minimum luminance.

Funding / Grants

  • IHBI (2019 - 2020)