A Study on Optimizing Infrared Heating Technology for Asphalt Pavement Maintenance and Rehabilitation

Abstract

In Canada especially, cracking and potholes on asphalt concrete pavements is a continuous problem requiring constant repairs. With the increased expansion and use of asphalt pavement infrastructure, combined with more severe climactic conditions and freeze thaw cycles experienced by asphalt pavements, pavement maintenance and repair practices need to improve the quality and longevity of their repairs. When compared to current standard crack and pothole repair processes such as crack sealing, crack filling, and full milling and replacement, infrared heating repairs can consistently provide a longer lasting repair then crack sealing, crack filling, and mill and replace patch repairs. Infrared heating repairs provide a repair which is more cost effective than full roadway replacement, with significantly longer lifespans than most conventional repair methods, filling in an intermediary repair gap present in the current pavement maintenance roster. The City of Waterloo cooperated with University of Waterloo’s Centre for Pavement and Transportation Technology and infrared heating manufacturer Heat Design Equipment Inc. (HDE) to evaluate the use of infrared heating repairs on a local project. This project was located along Sugarbush Drive which requires major pavement rehabilitation. Upon visual inspection, and laboratory testing completed on the asphalt, granular base course, and subgrade materials, results indicated that Sugarbush Drive was a prime candidate for infrared heating repairs, mainly because the sampled asphalt cores contained high percentages of asphalt binder. It was recommended that the City of Waterloo proceed with the use of infrared heating technology to repair the entirety of Sugarbush Drive, and continue partnership with CPATT to observe and record the performance of the repair throughout the road’s lifespan. The development of a patching mixture utilizing infrared heating consisted of using reclaimed asphalt pavement (RAP) and rejuvenating agents. The properties of three different RAP sources were evaluated through laboratory testing in order to determine their respective performance gradings. Good performance was achieved from two of the standard RAP sources retrieved from previously used milled asphalt pavement materials from the region, however, extremely high stiffness was observed from a RAP source consisting of unused excess asphalt mixtures, and further testing was recommended to confirm the properties of the RAP source.