CONTINUED DETERMINATION OF THE INFLUENCE OF IMPORTANT MATERIAL/TECHNICAL FACTORS AND MIXTURE COMPOSITION ON THE WEAR OF BITUMINOUS ROAD SURFACINGS

WEITERFUEHRUNG DER ERMITTLUNG DES EINFLUSSES DER WICHTIGEN MATERIALTECHNISCHEN FAKTOREN UND DER MISCHGUTZUSAMMENSETZUNG AUF DEN VERSCHLEISS BITUMINOESER FAHRBAHNDECKEN

RESEARCH PROJECT NUMBER 7.004 G 73 1 (IRRD NO. 700176) HAS ALREADY BEGUN TO EXAMINE THE MOST IMPORTANT MATERIAL FACTORS INFLUENCING THE WEAR BEHAVIOUR OF BITUMINOUS LAYERS. IN PARTICULAR THE STRESSES CAUSED BY WINTER TRAFFIC, SUCH AS ALTERNATING FREEZING AND THAWING, WET ROAD SURFACES, DEICING SALTS AND STUDDED OR OTHER WINTER TYRES HAVE TO BE CONSIDERED. HITHERTO 100 DIFFERENT MIXTURES HAVE BEEN EXAMINED FOR WEAR BY MEANS OF EQUIPMENT SIMULATING WEAR. THIS HOWEVER IS NOT ENOUGH TO MAKE A RELIABLE ASSESSMENT OF THE INFLUENCING FACTORS. THE WEAR TESTS ARE TO BE CONTINUED ON A FURTHER 120 MIXTURES. THEY WILL BE SELECTED AFTER AN EVALUATION OF THE AVAILABLE STUDY RESULTS. ASPHALTIC CONCRETES AS WELL AS GUSSASPHALTS ARE TO BE TESTED. THE MAIN VARIABLES ARE TO BE THE FOLLOWING: FILLER QUANTITIES AND QUALITY, BINDER QUANTITIES AND ADDITIVES TO THE BINDER, QUANTITIES AND QUALITY OF CRUSHED SAND, AND GAP-GRADED AGGREGATES IN ASPHALTIC CONCRETE. ONLY 2 OF THE 6 PIECES OF EQUIPMENT PREVIOUSLY USED ARE TO BE USED AGAIN.