Microwave Applicator for Thermal Treatment of Bituminous Surfaces

A comprehensive study of a microwave applicator for thermal treatment of bituminous surface is presented in this paper. The applicator consists of a customized rectangular waveguide horn surrounded with a hexagonal lattice of cylindrical chokes preventing hazardous leakage of microwave radiation beyond an exposure area. Electromagnetic simulations based on a finite-difference time-domain method are applied in a design process and afterward, the prototype is manufactured with the aid of computerized numerical control machining. Eventually, the applicator is applied for experimental testing of microwave-assisted thermal treatment of the trial bituminous surface, which demonstrates that microwave energy may be a viable alternative to typical thermal bonding techniques used in road construction and maintenance processes if appropriate conditions are met.