Effects of simulated day and night driving on the speed differential in tangent-curve transition: a pilot study using driving simulator

"Objective. The pilot study described in this paper is aimed at analyzing the driver speed profile for the evaluation of road design consistency during simulated day and night driving. The research, carried out using a driving simulator, is developed with the overall objectives of evaluating the speed differential during simulated night driving for the identification of critical road situations not detected by design consistency evaluation during simulated day driving.. . Methods. An existing two-lane rural road, where high accident rates were recorded during nighttime, was implemented in the driving simulator of the Inter-University Research Centre of Road Safety (CRISS) and the drivers speed profiles were recorded both in simulated day and night driving conditions over the 39 tangent-curve configurations that composed the road alignment.. . Results. The analysis of the speed differential based on 85MSR indicator during simulated day driving was not able to identify critical road situations that, on the contrary, the same analysis during the simulated night driving revealed. It occurred for the most of tangent-curve configurations.. . Conclusions. The study demonstrate that limiting the speed analysis only to day driving condition can not exclude the possibility that during the night driving some road configurations could become unsafe. The findings of the study highlight the need for carrying out design consistency evaluations also for night driving conditions.. "