Full Depth Recycling has been used in Western Canada since the early 1990’s. The use of Expanded Asphalt (Foamed Bitumen) as a Stabilizer in the Full Depth Reclamation process has been used in Eastern Canada since the late 1990’s. In 2001, the City of Edmonton, Alberta, contracted with a local contractor and Wirtgen GmbH for the construction of a demonstration project using Foamed Bitumen in the Full Depth Reclamation of three locations. Ellerslie Road consisted of 4 lane-km of a two-lane, low volume, rural section, 70 Avenue consisted of 3.1 lane-km of a two lane, light industrial, rural section and 150 Avenue consisted of 6 lane-km of a four lane, bus route collector roadway. With the assistance of AA Loudon and Partners, an Engineering Consultant from South Africa, a method specification for Foamed Bitumen Stabilization was developed for this demonstration project. The existing Hot Mix Asphalt (HMA), Oil mix and Granular / Soil Cement base were pulverized, had Foamed Bitumen added as a stabilizer, were re-graded and compacted. The process utilized in the demonstration projects also called for the addition of cement as active filler. Foamed Bitumen Stabilization was carried out to a depth of 200 to 225mm. The Foamed Bitumen Stabilization operation proceeded well and provided a smooth, hard, uniform surface suitable for the accommodation of detour traffic, and in the case of 150 Avenue, was used as a running surface for a six-week period. Generally the stabilized base was overlaid with HMA wearing course following a two-day curing period. This paper outlines the condition of the pavements prior to rehabilitation, basic design requirements, construction details, testing and evaluation completed and post-construction observations and monitoring of the three demonstration projects.
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