Induction Heating and Healing Behaviors of Asphalt Concretes Doped with Different Conductive Additives

Abstract

It is consensual that the self-healing property of asphalt concrete can repair the damage inside it during high temperature and rest period. In order to not affect the traffic, the rest period of asphalt pavement is very short and uncontrollable; so, it is necessary to obtain enough high temperature in a limited time to achieve higher healing efficiency of asphalt concrete. The purpose of this paper is to study the induction heating efficiency and healing behaviors of asphalt concretes doped with different conductive additives. Steel fiber, steel grit, and steel slag were added to asphalt mixtures as conductive additives to prepare induction healing asphalt concretes. The steel grit and steel slag were added to replace the aggregates of corresponding particle size by equal volume to ensure the consistency of asphalt concrete volume, which can avoid degrading the performance of asphalt concrete due to the change of porosity. The induction heating efficiency and healing rate of asphalt concrete were quantified by infrared camera and three-point bending-healing experiment, respectively. The results showed that the thermal properties of asphalt concrete changed with the addition of different conductive additives. The asphalt concrete with steel fiber had the best induction heating property. While steel slag had extremely weak induction heating speed, the better thermal insulation property of the asphalt concrete with steel slag resulted in a higher induction healing rate. It was suggested to add steel slag to induction healing asphalt concrete to improve the healing rate.

Simulation Analysis of Induction Heating as a Self-Healing Method on Asphalt

“…To solve this problem, conductive materials must be added to the asphalt mixture. Some conductive filler materials can be used, but steel fiber is the most common material used as an addition to increase the overall electricity of the asphalt [13,15,16,33,34]. The systematic overview of the induction healing mechanism is shown in Figure 4.…”

Numerical Analysis of Bifilar Coil Geometry on Induction Heating Performance for Self-healing Asphalt

“…The most common material used as an additive is steel fiber. This additive can increase the asphalt's overall electrical conductivity [35][36][37] .…”

Energy Consumption and Environment Performance Analysis of Induction-Healed Asphalt Pavement by Life Cycle Assessment (LCA)

“…This stage includes resource consumption and GHG emissions from the development and transportation of the materials (asphalt, cement, coarse aggregate, mineral powder, fine aggregate, steel fiber). In addition to the raw materials of the traditional asphalt mixture, the key to the self-repairing asphalt pavement in this paper is the addition of steel fiber [ 16 , 23 , 24 ]. In the material manufacturing stage of raw materials, the production energy consumption and related emissions data of various materials are based on the existing database and relevant industrial environment and energy reports, while the transportation distance between the material manufacturer and the mixing station is recorded and converted to the calculated value according to the actual data of the project test section cases [ 25 , 26 , 27 ].…”