A Study Of Applied Technology In Deicing And Melting Snow For Road Surface By Carbon-fiber Electrical Heating Wire

It is well known that ice or snow accumulation on the road surface has great influences on transportation in cold winters. Not only does it affect traffic safety and life of inhabitants severely, but also it is a potential danger to national economy development.However, the most commonly method where deicing salt is used could reduce the endurance of the concrete road surface, and destroy establishment of the roadway and pollute the environment.Therefore,it is great important to seeking the new method of deicing or melting snow.In this paper, backgroud of deicing and snow melting for road in winter, the carbon-fiber electric-heating-wire is used in concrete road, this dissertation makes use of the Joule heating effect of electric-heating-wire concrete to deice or melt snow. And bases on the theory of heating transfer, main factors when used the electro-thermal effect of carbon-fiber electric-heating-line for deicing and snow melting are studied. The study in this paper will provide a theoretical and experimental basis for the future application of carbon-fiber electric-heating-wire concrete. The main research works are described as follows:(1) Based on the energy conservation law, the temperature heating and cooling differential equations of carbon-fiber electric-heating-line concrete under electric heating are established and solved. Then the temperature variation curves during heating and cooling are achieved, the curves express comprehensively the effect of section shape and size, surface area of thermal losing, electric heating power output, and coefficients of convective and radiant heat transfer on the temperature variation regularity. The temperature increasing and decreasing curves are measured in laboratory and the experimental results are consistent with those computed by the temperature variation curves.(2) Using the electro-thermal effect of carbon-fiber electric-heating-wire for road surface deicing or snow-melting, main parameters affecting heat losing are convection and radiation. Wind scale, environmental temperature, and heat insulation layer significantly affect on heat losing. The relationship between the surface temperature of concrete slab and the wind scale, environmental temperature at different input power is researched. By comparing the models with and without heat insulation layer, different effects on heating concrete slab are described in this paper. These researches provide an important basis of concrete road surface heating system for deicing or snow-melting with carbon-fiber electric-heating-wire. (3) Established the heating apparatus for deicing or snow-melting by carbon-fiber electric-heating-line, the space of laying the carbon-fiber electric-heating-line is studied, the results show that the space is 10 cm, the uniformity thermal energy produced by carbon-fiber electric-heating-line under electric heating can meet the requirement of deicing or snow-melting for road surface.(4) The deicing or snow-melting in laboratory (in the freezer) experiment was carried out, the relationship between the melting time of snow or ice and the input power, circumstance temperature, snow or ice thickness are studied, and then application of concrete slab for deicing or snow-melting in field was studied. The results show that the range of power consumption per square meter form 500 W/m~2 to 1000 W/m~2, the thermal energy produced by carbon-fiber electric-heating-line under electric heating can meet the requirement of deicing or snow-melting effectively for road surface.