Effectiveness of a roundabout rerouting signalization scheme for road works

Safe work zones are very important to road authorities. The European Parliament emphasizes this and “Calls on the Commission to ensure that road work sites are made safer through guidelines for designing and equipping sites […]; calls for guidelines, which should include proper signing, removal of original road markings […]”. The Flemish Agency for Roads & Traffic created different standard signalization schemes which ought to be used at road work sites. One of these schemes deals with the signalization of road works at a roundabout. Goal of this study was to test the comprehensibility of the proposed signalization by means of a driving simulator and to evaluate if drivers could reach the destination. Fifty participants drove seven different routes (3.5 km) in a randomized order fixed-base simulator (NADS MiniSim™). The scenarios consisted of a realistic Flemish road in which the signalization scheme was implemented. Drivers were instructed to drive as they normally do and to drive to one of four destinations. The western roundabout branch was closed because of road works and participants needed to follow a detour. The route choice behavior of the participants at two decision points was qualified as correct or incorrect. Across scenarios, 23% to 90% of the participants could reach the destination. Based on these results, several recommendations were provided. One important adaptation was recommended in the route where participants needed to use the roundabout clockwise (only 23% did this correctly). Drivers who did not comply to the signalization instructions in this situation, verbally gave the comment that the information at the advance direction sign in this route was not clear. Therefore, we suggest to modify the advance direction sign at this place. Another recommendation is to change the general temporary direction signs “detour” by specific temporary direction signs which state the municipality name.