Study On The Performance Of Asphalt Pavement With Snow Melt Salt

Road Icy can make friction coefficient of road surface too low to seriously affect transportation security, which is a difficult problem for administrator. How to scientifically and effectively solve the problem becomes the focus of all circles. The asphalt pavement with snow melt salt has opened up a new method in solving this problem. Salt is added into asphalt mixture directly to replace the different parts of mineral aggregates to format new asphalt mixture. The active ingredients in salt becomes solution when salt encounter with water. Freezing temperature of water is reduced, which can realize the purpose of anti-freezing and snow melting. The snow melt mechanism and road performance of asphalt pavement with snow melt salt are systematically studied in this paper.The. salt content of asphalt mixture with snow melt salt is detemined by density equivalent substitution method. The results of tests indicate that the conventional road performance such as the water stability, the high temperature stability, the low temperature anti-crack performance can satisfy requirement. Matters which should be paid attention in the testing process are proposed. The mechanism of reducing the freezing temperature of water is explained based on the vapor pressure drop theory. The melting processes of asphalt pavement with different kinds of snow melt salt are analyzed. Focusing on the snow melt characteristics of asphalt pavement with snow melt salt, freezing delayed, thin ice pendulum tester method, snow melting and melting accelerating method are used to evaluate its short-term snow melt effect. The method of effective ingredients of salt dissolving out when soaked, accelerate dissolution and other test methods are adopted to evaluate its long-term snow melt effect. The results of tests show that its snow melting performance is good. But its long-term water stability is a bit poorer than common asphalt xiture.The influences of some factors such as temperature, rainfall duration to salt dissolving are analyzed based on asphalt mixture climate zone. The climate zone of asphalt pavement with snow melt salt is proposed, and based on which, the guiding principle of asphalt pavement with snow melt salt design for different climate zones is proposed. Finally, asphalt pavement with snow melt salt paved experience at home and abroad is summarized. The construction technique of asphalt pavement with snow melt salt and the validation method of effective ingredients are proposed.