Estimation of Pavement Surface Freezing Indices

A rational and usable correlation between the freezing index values determined from air temperatures and from pavement surface temperatures has been developed. Data for the study were obtained by field measurement by means of thermocouples connected to a continuous recorder. Thirteen measurement sites were selected to include bituminous and concrete pavements within West Virginia. Multiple linear regression analyses were performed for each site to relate the air temperatures to the pavement temperatures, assuming that the air temperature varied in a sinusoidal fashion. The effects of solar and net longwave radiation were considered. An equation is developed for the estimation of pavement surface freezing index. This is easily adapted to computer solution to facilitate design use. It is demonstrated that the ratio of pavement surface freezing index to air temperature freezing index varies by geographic location and severity of winter.