Abstract
One of the most important factors determining the skidding resistance of a bituminous road is the polishing resistance of the aggregate appearing in the road surface. A study has been made of the factors that affect the results of polished-stone value (PSV) tests. These factors can be separated into those connected with the test procedure itself and those arising from the production of the aggregate and from sampling procedures. The 7 main conclusions that were drawn from this study are discussed.