Skid Resistance in Austrian Tunnels with Special Attention to Concrete Pavements

The skid resistance of a road surface is of high importance for road safety. All kinds of controllable acceleration, deceleration and steering actions are only possible, if the road surface offers at least the same adhesion as the driver’s action requires. It gets even more difficult due to the fact that the driver can not perceive the skid resistance level of a wet road surface and can not adapt his driving behaviour. In Austria skid resistance measurements are carried out periodically with the high performance measuring vehicle RoadSTAR. In addition, skid resistance acceptance tests and tests at the end of the guarantee-period are mandatory on new road pavements of the motorway network of Austria. The data evaluation of the friction measurements, especially the measurements of the acceptance tests pointed out, that the values of skid resistance in tunnels are noticeable lower than those of the other sections of the road network. Because of this problem a national research project has been started to analyse these friction data in detail and to find some indications for the skid resistance problems in tunnels. In this paper the results of the first step of this research project are presented.