Study On The Functional Characteristics Of Electromagnetic Induction Asphalt Pavement Under The Action Of The Magnetic Concentrating Layer

The electromagnetic induction asphalt pavement is widely used because it can achieve self-healing,ice/snow melting at the same time However,there are problems with slow induction heating rate(IHR)and poor function effect.In order to solve the above problems,researchers start with energy conversion of the pavement,namely,improving the energy conversion efficiency(ECE)of the first stage"electric energy to magnetic energy"and the third stage"electric energy to thermal energy".Although the IHR and functional effect can be improved to some extent,it does not fundamentally solve the problem.Actually,the serious’magnetic leakage phenomenon’in the second stage of the’magnetic energy-electric energy’is the essential reason for the above problems,resulting the waste of the magnetic energy.This is also the most important reasons why the heating effect of pavement is relatively low compared to its potential heating effect.Therefore,this paper intends to focus on the second stage of the‘magnetic energy-electric energy’conversion process.An asphalt magnetic concentrating layer(AMCL)with the function of‘magnetic absorption’and‘magnetic concentration’was designed based on the pavement structure.It is laid between the asphalt middle layer embedded with induction coil and the asphalt lower layer.On the one hand,it has the functions of waterproofing and strengthening the adhesion between layers;on the other hand,it can guide the magnetic energy,which is diverged into space due to the‘magnetic leakage phenomenon’,into the induction surface layer,thereby increasing the ECE of"magnetic energy-electric energy"and IHR,and improving the pavement function.In this study,firstly,the waste steel shavings were added to the asphalt mixture to prepare the induction surface layer,and the waste ferrites were mixed with asphalt to prepare two kinds of AMCL,including graded AMCL and single particle size AMCL.Then,waterproof test,shear test and pull-out test are used to test the waterproof performance and bonding performance of the AMCL.At the same time,the heating rate,self-healing rate,ice-melting rate and energy conversion improvement rate were proposed to evaluate the influence of waste steel shavings content and type of AMCL on the pavement function effect in induction heating test,self-healing test and ice-melting test.Based on the above four evaluation results,it is recommended that the optimal content of waste steel shavings was 6%,and the graded AMCL was optimal.Finally,the economic benefits and environmental protection value of the 1km long unit pavement under the action of the AMCL for 1 hour of operation are predicted and analyzed.It was found that the cost of electric energy saved by AMCL in an hour is almost four times of its own construction cost.At the same time,compared with the traditional electromagnetic induction asphalt pavement,when the ice melting function is realized under the action of AMCL,the carbon dioxide emission can be reduced by 5.43×10~5kg in one hour.