New methodological approach for glare analysis on tunnel endpoints

When entering and exiting tunnels, high luminance variations may cause severe crashes due to the occurrence of glare and the blackout effect. In this study, we propose a methodology that will effectively minimise the exaggerated light variations that arise over a short distance at the tunnel endpoints. An underpass which has the same characteristics of a tunnel in Brisbane, Australia was selected as a case study; a 3D model of the tunnel was created using Points Clouds, Digital Elevation Model and Open Street Maps. GrasshopperͲforͲRhino was used to merge this information in order to create the tunnel's model. The Radiance lighting simulation engine was used to simulate the High Dynamic Range (HDR) images from the drivers' field of view (FOV) to accurately understand their visual experience. These images were postͲprocessed by Evalglare to conduct advanced daylighting and glare analysis. Luminance maps highlighted the problem of high contrast and glare probability in the tunnel entrance. The beneficial outcome of the proposed methodology is not only evaluating glare problems, but also allowing for the optimisation of preͲtunnel lighting that utilizes daylight to maximize energy savings. Thus, the effectiveness of the solar techniques in reducing the contrast and creating a transitional zone that blends the highly illuminated outside with the dark interior can be evaluated.