The use of salt being questioned more and more by road users, the general public and politicians. For this reason extensive research has been conducted to find more efficient ways of using salt and also to find less harmful alternative de-icers. The spreading of prewetted salt or saline solutions are methods which have been used for many years and they now are fairly well known techniques. Water, NaCl or CaCl2 solutions can be used for prewetting the salt, where the two former are most commonly used in Sweden. Studies of CMA (calcium magnesium acetate) have been carried out in Sweden since the beginning of the 1980s. Due to the high price of CMA, at least 20 times that of salt, laboratory and field tests have recently been done with mixtures of CMA and salt. The expected reduction of corrosion was however not as large as earlier results from laboratory studies, found in literature, had suggested. A chemical closely related to CMA is potassium acetate (KAc). KAc was developed mainly as an alternative to urea for runway deicing. After being tested both in laboratory and in field KAc has replaced urea on many airfields in Sweden. Calcium chloride (CaCl2) is used to some extent in the USA and also in some European countries. It is mainly used as a solution for prewetting of salt and at low temperatures also instead of salt. In Sweden CaCl2-solutions for prewetting salt and/or as a deicing agent have however lately been discussed and a literature review has been carried out. The conclusions drawn from the literature review and some ice melting effect on CaCl2 is lost when using a solution and that the de-icing effect is about the same as for NaCl for temperatures above minus 10 degree Centigrade. To reduce the risk of skidding at more exposed places, tests have also been carried out for many years with rubberised pavements and asphalt concrete with salt additives. Two salt additives have been tested, Verglimit and recently also Grikol. Both consist mainly of CaCl2. The conclusion from the earlier tests were that these types of pavements do not have any significant skid-preventive effect, except at some occasions with temperatures around zero degrees Centigrade and hoarfrost. (A) For the covering abstract of the conference see ITRD E202707.
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