Ontario’s Experience in the Construction of Perpetual Pavement Trials

As part of the on going effort to promote sustainability in the design, construction, and maintenance of highway infrastructure, the Ministry of Transportation, Ontario (MTO) has identified the need to construct perpetual pavements on major highways. It is anticipated that this approach will reduce major rehabilitation works and the associated green house gas emissions by reducing traffic delays associated with major construction. In 2006, the first perpetual pavement trial with Rich Bottom Mix (RBM) was constructed on Highway 406, near Thorold. Subsequently, two more perpetual pavement trial projects were identified for construction on Highway 7, Carleton Place and Hwy 401, Woodstock in Ontario. The trial section on Highway 401 is divided into three segments: perpetual pavement section with RBM; perpetual pavement section without RBM; and conventional flexible pavement control section. All three segments will be instrumented in collaboration with the Centre for Pavement and Transportation Technology at the University of Waterloo, Ontario, to better understand the behaviour of the different layers in each section under various traffic loadings and environmental conditions. More specifically, the basic concept used in the perpetual pavement design will be evaluated through long-term monitoring of pavement performance through instrumentation as well as the traditional approach which includes manual distress surveys, and measurements of deflection, roughness and rutting. This paper describes briefly the experience gained in the construction of perpetual pavement design test sections in Ontario focussing mainly on the design and construction of rich bottom mix, and the instrumentation of the test sections.