The concrete industry felt the thrill of victory when Medicine Hat, Alberta, decided to replace deteriorated asphalt intersections on the Trans-Canada Highway with concrete. Robert Seme, regional paving engineer of the Canadian Portland Cement Association's western region, calls the project "the largest major intersection rehab in concrete in Canada." About 140,000 square feet of concrete pavement were used to restore the asphalt intersections and intersection approach lanes.
The Canadian city, which typically uses asphalt as a paving material, chose not to select the lowest-priced solution. Instead, it decided to increase the budget for the project and use concrete at the intersections and some turn lanes and use improved high-strength asphalt elsewhere. Concrete was chosen because it doesn't rut, and it has a life of at least 40 years compared with only 10 to 15 years for asphalt. Also, the existing pavement could be milled down to accommodate a concrete pavement, saving curb and gutter.
The project general contractor, MEDICAN Construction Ltd., used a four-track slipform paver to place the concrete pavement in 12-foot-wide passes. An inserter attachment on the slipform paver automatically inserted dowels at 27.6-inch on-center spacings. The paver also has an automatic float attachment, so little hand finishing was needed. Workers simply tined the concrete behind the float then applied curing compound.