The Temperature Field Characteristic And Energy Conversion Rule Of The Inductive Heating Asphalt Pavement

The inductive heating asphalt pavement(IHAP)has been widely used to achieve various pavement functions,such as snow-melting,self-healing,hot recycling and pavement maintenance.However,there are some existing problems,such as insufficient heating speed,non-uniform temperature distribution and insufficient energy utilization efficiency.These problems have negative effects on the above functions.To solve the above problems,this study investigates the temperature distribution of traditional IHAP from the perspectives of the experiment and simulation.On this basis,the magnetically controlled inductive heating asphalt pavement was proposed based on magnetic flux concentration technology,which aims to improve the heating speed and energy utilization efficiency,and obtain more uniform temperature distribution at the same time.To improve the heating efficiency and mitigate the non-uniform temperature distribution simultaneously,IHAP containing waste steel shavings(WSS)was designed,and its preparation method was proposed.The induction heating experiments were conducted,and based on the experimental results,a comprehensive evaluation method was proposed to improve the heating efficiency and temperature uniformity at the same time.It is recommended to use as optimum scheme: 10% wt.of WSS content 3Kw power,55 k Hz frequency of the induction generator.To further analyze the temperature field distribution characteristics,a novel dispersed heat source simulation method was proposed.2-D geometric model of IHAP was established through modified random aggregate algorithm,and based on the above model,the induction heating simulation of IHAP was conducted.The effects of operating parameters,material composition,and environmental factors on the maximal and average temperature of the pavement surface were analyzed,and the prediction models of the temperature of the pavement surface were proposed,which can be the guidance for the temperature regulation of IHAP.It is found that the above problems cannot be solved simultaneously by the investigation of traditional IHAP.Thus,based on the magnetic flux concentration technology,a novel functional asphalt magnetically concentration layer(MCL),whose aggregate is replaced by waste ferrites(WF).The design and the preparation method of MCL were investigated,and its pavement performances were studied.The results show that MCL,which is functional layer of the IHAP,meet the basic requirements of the pavement performances.Based on the MCL,the magnetically controlled inductive heating asphalt pavement was proposed.Its pavement model was established by the above simulation method,and its induction heating simulation was conducted.The effects of MCL on the energy utilization efficiency and the temperature distribution of IHAP were analyzed,and the material composition of IHAP and operating parameters were optimized.It is recommended to use as optimum scheme: 400-500 A current amplitude,50-60 k Hz current frequency of the induction generator,12 min heating time and 4% wt.of WSS content.