Implementation of Cold In-Place Recycling with Expanded Asphalt Technology in Canada (05-2531)
Becca Lane, Ontario Ministry of Transportation, Canada
Thomas J. Kazmierowski, Golder Associates Ltd., Canada

Cold In-place Recycling (CIR) is a pavement rehabilitation method that processes an existing hot mix pavement, sizes it, mixes in additional asphalt cement, and lays it back down without off-site hauling and processing. The added asphalt cement is typically emulsified asphalt. A recent development in CIR technology is the use of expanded (foamed) asphalt, rather than emulsified asphalt to bind the mix. This combination of CIR and expanded asphalt technologies is termed Cold In-Place Recycled Expanded Asphalt Mix (CIREAM). The Ministry of Transportation Ontario (MTO) constructed a CIREAM trial section on Highway 7, in July 2003. The 5-km CIREAM trial section was constructed adjacent to 8-km of conventional CIR. CIREAM placement resulted in a smooth, hard, uniform surface, providing an excellent platform for paving operations. The CIREAM placement progressed in a continuous and efficient manner, placing 5 km over a three-day period. Indirect tensile strength testing was carried out on both materials during construction. Falling Weight Deflectometer (FWD) testing and evaluation of pavement roughness and rutting using MTO’s Automatic Road Analyzer (ARAN) were carried out. Resilient modulus testing was also carried out on core samples of the CIR and CIREAM. FWD, ARAN and resilient modulus test results indicate that the CIR and CIREAM pavements are performing similarly. A field review one year after construction showed no discernable distortion, rutting, or cracking. Based on short-term results, CIREAM appears to be an acceptable in-place recycling/rehabilitation strategy that provides an economic alternative to conventional CIR, reducing curing time, and extending the construction season.