STUDY OF THE USE OF MIXED SALTS TO PREVENT THE FORMATION OF BLACK ICE

UNTERSUCHUNG DER ANWENDBARKEIT VON MISCHSALZEN ZUR GLAETTEBEKAEMPFUNG

ON HIGH MOUNTAIN ROADS IN AUSTRIA AND SWITZERLAND MIXTURES OF COMMON SALT (NACL) AND CALCIUM CHLORIDE (CACL2) ARE USED AT VERY LOW TEMPERATURES TO ACT AGAINST BLACK ICE.A STUDY IS TO BE CARRIED OUT TO SEE WHETHER WHEN SUCH MIXTURES ARE USED ON ROADS IN AREAS WITH HIGHER TEMPERATURES IT IS POSSIBLE TO DECREASE THE AMOUNTS SCATTERED FOR REASONS OF ENVIRONMENTAL PROTECTION,AND THEREBY TO ATTAIN OPERATIONAL IMPROVEMENTS AND COST SAVINGS.THE INVESTIGATIONS WILL COMPRISE THE TESTING OF THE DE-ICING EFFECTIVENESS OF VARIOUS MIXTURES IN THE COLD ROOM,THE CARRYING OUT OF PRACTICAL TRIALS WITH THESE MIXTURES,THE TESTING OF THE STATE OF THE ROAD COMPARED WITH ROAD SECTIONS TREATED WITH NORMAL DE-ICING SALT (NCAL) , THE DETERMINATION OF THE AMOUNTS OF SALT TO BE SPREAD,THE NUMBER OF PASSES REQUIRED AND A COST COMPARISON OF THE TWO METHODS.