Abstract Manager

The Highway 401 Expansion project is a Design Build project to widen 18km from Credit River in Mississauga to Regional Road 25 in Milton, from the 3 lanes in each direction to 5 lane sections and 6 lane (collector/express) sections. It’s a $650M project that was built under a very aggressive schedule to be constructed in under 4 years. Highway 401 is the busiest and most congested highway in North America, carrying approximately 180,000 vehicles on average per weekday from Credit River to Regional Road 25.

One of the most complicated aspects of the project was to maintain traffic during construction. The staging approach involved widening the highway to the outside, then shifting traffic to the widened portion and then reconstructing the median portion of the highway. The traditional method to have done the reconstruction in the median would be to remove the existing road (asphalt, concrete base, aggregate & concrete barrier walls) and transport them in trucks off-site, then process followed by transport granular material from off-site to build the road base and sub-base. However, this approach would require trucking an extremely large quantity of material off-site for disposal and inversely transporting a large amount of material to the site from aggregate sources, which has the added complication of trucks having to cross 3 lanes of live traffic to leave the site, while also having to have a lot of fuel consumption for transporting all that material.

The project team looked at this activity to determine whether there was a better alternative approach. Based on the quantities, it was determined that it would be feasible to bring crushers on-site to recycle the asphalt and concrete to produce granular material that would meet the requirements for Granular A to be used in the pavement structure. Four of these crushers were brought on-site to continuously crush the material, which was transported and placed on-stie without the need for off-site trucking. Not only did this recycle a lot of material, but it also had the added benefit of reducing the amount of truck traffic on highway 401, reducing the amount of interface with trucks, which improves safety for the travelling public and reduces the amount of congestion on Highway 401.