Optimization of Steel Fiber Used for Induction Heating in Porous Asphalt Concrete

Abstract

An electrically conductive porous asphalt concrete used for induction heating and subsequently healing of cracks is prepared by adding conductive materials (steel fibers and steel wool) in this research. In this paper, the optimization of steel fiber used for induction heating is reported based on the electrical resistivity, induction heating speed and particle loss resistance of porous asphalt concrete. It is found that porous asphalt concrete containing steel fiber with smaller diameter or longer steel fiber is more electrically conductive and induction heatable than that containing the same content of steel fiber with bigger diameter or short steel fiber. It is also found that steel wool type 00 with length of 9.5 mm is more effective than short steel fiber type 1 and steel wool type 000 to improve the particle resistance of porous asphalt concrete. Finally, 8% (by volume of bitumen) of steel wool type 00 is considered as the best option used for induction heating in porous asphalt concrete.