Research On The Melting Of Ice And Snow Pavement With Electric Heating Asphalt Film

In winter,snow and ice on the road surface not only reduces the road capacity,but also a serious threat to road traffic safety.Therefore,rapid and efficient snow or ice removal is a necessary work for winter road maintenance.The basic way of road deicing is nothing more than to promote ablation and manual or mechanical cleaning.In promoting the melting of snow and ice,at present,besides the chemical methods of deicing salt or snow melting agent,the road engineering field has also developed physical methods such as electric-heating,fluid tube heating and external heating.Among them,the longtime electric-heating method is simple in principle,difficult in construction,and has been widely used.So far,there are two kinds of electric-heating pavement developed in road engineering field:A.conductive heating cable/electric-heating wire;B.conductive heating asphalt or cement paving layer.The former is embedded at the 4cm⁶cm below the road surface,and has a certain influence on the force of the road surface.It cannot solve the contradiction between the durability of structure and heating efficiency.The latter often uses the sandwich structure to be used in the middle/lower layers of asphalt,which has the problems of large heat storage and low heating efficiency.Therefore,further research should be done on the problem of electric-heating deicing road.In this study,an electric-heating asphalt film with thickness of 1²mm is proposed as the new type of conductive heating pavement structure.The scheme is similar to the"sandwich"structure of the conductive heating asphalt layer,using an asphalt mortar with a higher conductivity to be laid between the abrasive layer and the under layer with a seal or adhesive construction process,and then access the safety circuit to generate heat.However,compared with the heating scheme of the conductive asphalt layer,the structure of the asphalt film itself has little heat storage,higher heating efficiency and lower construction cost.Compared with the heating cable/hot wire scheme,the electric-heating asphalt film does not change the force behavior of the road surface,the heating is more uniform,and the principle of the circuit decides that the local damage is not invalid.Firstly,the development of high conductivity asphalt mortar was carried out.A conductive asphalt mortar with the main components of asphalt,graphite and chopped carbon fiber was optimized by the conductivity test.The resistivity of the conductive asphalt mortar was 10^-2?·m,which could achieve the heating target of 450W/m² under safe voltage.At the same time,it is proved that it has excellent mechanical properties and construction performance as pavement structure layer materials based on shear test,anti-drawing test and anti-construction disturbance test.Then,according to the technical characteristics of the developed material,the design and analysis of the asphalt pavement structure and the circuit design,a feasible structure is put forward under the waterproof wear layer with the adhesive layer construction technology.The way of heating electrode arrangement and safety circuit for electric heating asphalt film is put forward.The combination of electric power,electrode and film thickness can be set under the safe voltage.The numerical simulation is used to analyze the deicing performance of the electric-heating asphalt film scheme.The results show that the scheme can achieve the goal of deicing.Meanwhile the composite plate specimens of outdoor ice and snow melting test also confirmed this conclusion.Finally,the comparison between the construction cost and the operating cost is carried out on the similar schemes of the electric-heating asphalt film and the conductive asphalt pavement.The results show that the electric-heating asphalt film scheme has obvious advantages in terms of construction cost and operating cost.In summary,the electric-heating asphalt film scheme presented in this paper provides a new technical idea for the deicing of electric heating pavement.The technical balance of the four aspects of the safety,efficiency,durability and controllable cost of the deicing technology is basically realized.With the development of new energy technologies such as road-surface power generation,there is no shortage of prospects.Therefore,it is worth further research and exploration.