This paper presents original research, and summarizes the published literature regarding tests of tire-road friction in winter conditions. The original research investigated the effect of temperature variation on tire-road friction on a variety of winter driving surfaces, including an investigation of the variation of friction coefficient with the dispersion rate of applied sand. Tests were conducted on surfaces including bare asphalt, black ice, ice and snow, ice and snow with a variety of sand overlays, ice and snow with a layer of fresh snow, and glare ice at temperatures ranging from -42 degrees C to -4 degrees C (-44 degrees F to 25 degrees F). The published literature relating to tests of friction in winter driving conditions was surveyed. Data from the original research and the previous publications is presented in a uniform fashion. (A)
Abstract