The ice-melting effectiveness of sodium chloride (sc), "qwiksalt(registered trademark) plus pci (registered trademark) granular reduced corrosion road deicer" (qwiksalt or qs) and "freezgard (registered trademark) plus pci (registered trademark) liquid reduced corrosion road deicer" (freezgard or fg) with respect to the removal of ice from highways was studied by laboratory experimentation. Qs is a solid consisting of a mixture of sc, magnesium chloride, water, and alignin-based biodegradable corrosion inhibitor called pci corrosioncontrol polymer. Fg is a concentrated aqueous solution of magnesiumchloride and pci. The rate of melting of ice by salts was investigated by two variants of a "blotter" method in which the aqueous saline solution generated by the melting of ice and dissolving of salt isabsorbed onto a tared blotter paper and weighed. The effects of several different conditions of relative humidity, temperature, treatment time, and extent of application of the deicers were studied. Results are reported as grams of saline solution generated per square meter of ice surface and also as estimated net pounds of water generated per lane-mile (63, 360 sq ft). Some preliminary experiments were conducted to estimate the effectiveness of the preparations with respect to penetration of ice and debonding of the ice-concrete interface. Relative to sc, qwiksalt generates brine more rapidly during treatment times up to 30 min. Differences are observed especially under conditions of low temperature and low relative humidity, for example, at -18 deg c and about 5 to 20% relative humidity. Freezgard formsbrine very rapidly, although less extensively than qs or sc. These new deicers should find many important applications. This paper appears in transportation research record no. 1246, Winter maintenance, roadside management, and rating routine maintenance activities.
Samenvatting