Determination and prediction of pavement skid resistance-connecting research and practice

Adequate pavement skid resistance is a key requirement for safe road operations. Unfortunately, the measurement and prediction of the skid resistance property of an in-service road pavement, or pavement mixture specimens in the laboratory, is a highly challenging process from both theoretical and practical points of view. For more than 60 years, owing to the lack of theoretical solutions to the complex tire-fluid-pavement interaction problem, the practice of pavement skid resistance determination and prediction has essentially been derived from experimental and field observed data. The rapid development of efficient numerical computational techniques and high-power computing facilities in the last two decades made it possible for researchers to numerically solve the tire-fluidpavement interaction problem. It enables the numerical evaluation and prediction of high-speed wet skid resistance, and the determination of the tire-pavement kinetic friction coefficient in the evaluation of low-speed skid resistance. This paper presents a state-of-the-art review of the research development of theoretical mechanistic approaches in the determination and prediction of pavement skid resistance. It covers the following main aspects of the subject matter: (i) mechanisms of skid resistance generation in dry, wetted (i.e., damp), wet and flooded pavements; (ii) theoretical evaluation of pavement skid resistance in dry, wetted, wet and flooded states; (iii) theoretical approaches in pavement skid resistance prediction; and (iv) concepts of representing the skid resistance state of pavement. The capability of finite element simulation approach for wet skid resistance evaluation with good accuracy is explained. Also highlighted is the practical significance of the Concept of Skid Resistance State. Areas of practical applications of the concept, coupled with the simulation model, are introduced. They include applications in driving safety analysis, road safety design and control, design of paving mixtures, safety maintenance and management of pavements, and harmonization of skid resistance measurements and predictions.