The Reuse of Old Pitch Containing Asphalt in Cement Bound Base Courses Depending on the Level of Harmful Substances

Large quantities of old asphalt containing varying admixtures of tar/pitch are produced during the renewal of asphalt roads. These pitches contain environmentally relevant substances such as pnlyr.yr.lic aromatic hydrocarbons (PAHs) and phenols which must not be allowed to leach out into the ground water. The intention is to bind the harmful substances in base courses used for road construction by stabilization with cement to make them environmentally safe. The suitability for road construction and the leaching characteristics of the base course were tested with starting materials with different contents of harmful substances.