Spragues Road Rehabilitation with an Unbonded Concrete Overlay Region of Waterloo, Ontario, Canada.

Abstract

The work of this project includes the rehabilitation and widening of a 1.2 km (0.75 mile) section of Spragues Road (Regional Road No. 75) from Wrigley Road to the Region of Waterloo boundary in the Township of North Dumfries. The existing road is a rural two-lane composite pavement with partially paved and gravel shoulders. An initial geotechnical investigation determined that conventional road resurfacing strategies of the asphalt / concrete composite pavement were no longer cost-effective and additional assessments were completed to evaluate alternate rehabilitation strategies. Through this process, non-destructive testing was conducted to determine the structural adequacy of the concrete base and suitability for pavement preservation. Comprehensive field investigations determined the 80-year old concrete base was generally in good condition and should be preserved as part of the project. The final pavement design consists of re-profiling or cold planing the existing asphalt surface to meet proposed design gradients, installation of an asphalt intermediate separation layer and placement on an Unbonded Concrete Overlay, a unique rehabilitation treatment in the Province of Ontario.