"A good skid resistance of the pavement surface is of essence for road safety. Loss of skid resistance can have dramatic material and loss of life consequences. The problem is aggravated further in the presence of water, due to the phenomenon of hydroplaning. In this project the micro-mechanical factors controlling skid resistance at the tyre-pavement interface in asphalt concrete pavements shall be identified and related to asphalt mix characteristics on the basis of experimental evidence and computational studies.In the first phase of the project, the skid resistance characteristics of various combinations of dry pavement surfaces and tyre types shall be evaluated experimentally. The tests shall provide the information necessary for micro-mechanical finite element simulations of tyre-pavement interaction. A state of the art 3D rolling contact algorithm, accurate representation of the tyre characteristics and the surface morphology shall be utilised. On the basis of the simulations, the parameters controlling the magnitude and the degradation of skid resistance in dry pavements shall be identified.These parameters shall be used as input for wet pavement analyses in the second phase of the project in which focus shall be placed on the detrimental influence of water on skid resistance. The rolling contact algorithm shall be extended by a hydrodynamic component to enable simulation of hydroplaning. On the basis of these simulations, the influence of water on the parameters controlling the magnitude and the degradation of skid resistance in wet pavements shall be identified. In particular, the influence of progressive pavement surface unevenness shall be investigated.Design tools will be produced for the evaluation of the critical asphalt mix parameters on the dry and wet skid resistance degradation as a function of tire type and driving speed. These can be used by road authorities to decide for the choice of safe driving speed limits."