The widening and reconstruction of Teston Road from 250 m West of Pine Valley Drive to Weston Road in the City of Vaughan, was a necessary yet complex project. During construction, one of the most important aspects was minimizing the traffic and disruptions to local commuters and residents. The project team was able to achieve that by widening the road one side at a time.

The bridge is a single span on Teston Road over Purpleville Creek Tributary C2 in Vaughan. The precast girders used for this project are modified NU 2400s that are 25mm wider than the standard section.

The precast concrete used included:

• 9 – NU 2400 Modified Girders
• Length = 45.6m
• Weight = 81.42 tonnes
• Exterior girders had 70 – 0.6” diameter strands and 6 – 0.6” diameter temporary strand for trucking, with a required transfer strength of 47.3 MPa.
• The interior girders had 66 – 0.6” diameter strands and 6 – 0.6” diameter temporary strands for trucking, with a required transfer strength of 45MPa.

These large, heavily prestressed girders posed the following challenges during production:

• Completing the setup in the casting bed and subsequent concrete pour at a steady pace to ensure a daily production cycle.
• Attaining the specified transfer strength (47.3MPa for exterior girders and 45.0MPa for interior girders) daily to ensure a daily production cycle.
• Transportation throughout the plant, in and out of moist curing, and in the yard. Two rubber-tired gantry cranes (70-ton and 100-ton Travelifts) were required to move these girders into the yard and load them onto the trucks.

The length and weight of the girder also posed challenges for shipping as haul route options to the project site were extremely limited.  Superload permits were obtained, and a preliminary assessment of the load's impact on a culvert spanning Cold Creek was completed prior to shipping the girders to the project site. A jeep and steerable dolly were used to deliver the girders to the east end of the bridge.  It was imperative that the access road at the east end of the bridge was a level compacted roadway as the lateral stability of the girders was close to the limits for factor of safety during transportation. Five (5) of the girders were delivered the day before the scheduled installation date and staged onsite to work around the GTA curfew that prevents movement of oversized/overweight loads into the area prior to 9:30 AM. This allowed the installation to start at 8:00 AM and thereby allowing all of the girders to be installed in just one day.

The installation utilized a brand new 700-ton LTM 1650 crane to lift the back end of the girder off the steerable dolly and over the valley while the other end remained on the truck.  The jeep then reversed towards the east abutment while the 700-ton crane moved the girder over the valley towards the west abutment. To allow this procedure to take place, a large quantity of reinforcing bars that projected from the east abutment needed to be cut down, thereby permitting passage of the girders over the east abutment. The west end of the girder was then passed to a 600-ton LTM 1500 crane located behind the west abutment and then the 700-ton crane lifted the east end of the girder off the truck. The girders were then lifted in tandem and set in place.

Precast concrete was an ideal solution to accelerate the overall construction schedule, reduce commuter impacts, and ensure a long lifespan and safety.