Improved approach for prediction of directional skid resistance based on directional pavement surface texture characteristics

Pavement skid resistance is commonly predicted from its statistical relationships with pavement texture indices, under the assumption of isotropic skid resistance and textural characteristics. The assumptions are incorrect because both skid resistance and surface texture of in-service pavements exhibit directional characteristics caused by uni-directional traffic polishing. This paper proposes a new approach for predicting directional skid resistance based on directional characteristics of pavement texture. Skid resistance and laser images of surface texture were measured from in-service pavements. Statistical equations were derived to relate directional texture indices with the corresponding skid resistance in the same direction. The results clearly indicated that, compared with the traditional method, the new approach produced significantly more correct and accurate predictions of in-service pavement skid resistance.