Microwave heating of asphalt paving materials: Principles, current status and next steps

Microwave heating could contribute to the sustainability of several operations in the construction and maintenance of asphalt pavements. This paper aims at describing the current status of this technology and pointing out the next steps to promote its spreading in the asphalt industry. According to this investigation, asphalt binders are not susceptible to microwaves, but some types of aggregates remarkably promote the heating process. The addition of steel slag, metallic fibers or carbon nanomaterials can also enhance energy efficiency. Nevertheless, the lack of laboratory standardization and the need for full-scale equipment and projects can slow the use of this technology. (C) 2020 Elsevier Ltd. All rights reserved.