Saskatchewan Department of Highways and Transportation (SDHT) is investigating alternate recycling and strengthening systems for in-service thin granular pavements in an attempt to improve granular pavement structural integrity through recycling and stabilization, as well as reduce the dependence on new source aggregates. This paper summarizes the findings of a pilot project investigating the mechanistic-climatic laboratory characterization of two typical Saskatchewan thin granular pavements stabilized in the lab with foamed asphalt, cement and asphalt emulsion. This research showed that conventional indirect tensile testing was relatively insensitive to the effects of foamed asphalt stabilization. In addition, conventional indirect tensile testing does not provide material constitutive relations across the full range of typical Saskatchewan field state conditions, including stress states and load frequencies. It was found that asphalt emulsion with cement significantly improved the mechanistic constitutive behaviour of both granular systems considered. This research also determined that foamed asphalt stabilization provided only marginal improvements in the unconfined compressive strength of post saturation and freeze-thaw climatic conditioning relative to the asphalt emulsion and cement stabilization system. For the covering abstract of this conference see ITRD number E216511.
Samenvatting