Alberta Transportation identified an intervention was required at six vehicular bridges on the provincial highway network in southern Alberta in order to extend their normal service life.
BF395 carrying Highway 3 over the Crowsnest River - Frank, Alberta
BF395 is located within the Crowsnest Pass carrying Highway 3 across the Crowsnest River. With over 8000 vehicles per day travelling along the corridor between Alberta and British Columbia, accommodating traffic during the peak summer season was critical to project success. Dillon developed strict contractual requirements to minimize the impact reduced lane widths and closures would have on the travelling public.
Built in 1955 as a three span cast in-place concrete structure with end span cantilevers the bridge was first rehabilitated in the 1980s. The work at that time included altering the end spans from cantilevers to conventional spans with the addition of piles at the abutment locations.
The initial scope of work included replacing the wearing surface with fibre-reinforced high performance concrete overlay, approach paving, and approach guardrail upgrades. During preliminary engineering, Dillon confirmed with Ground Penetrating Radar testing what was shown on the original design drawings - there was no bottom reinforcement in the end span girders. With no bottom reinforcement, positive moments in the end span would be resisted only by tension in the concrete, a condition that is not allowed by Code. Working closely with Alberta Transportation’s Technical Standards Branch, Dillon developed project specific specifications specifically for the design, supply, and installation of Fibre-Reinforced Polymer Wrap Systems to provide the required positive moment capacity.
BF7870 carrying Highway 24 over the Bow River - Carseland, Alberta
BF7870 carries Highway 24 over the Bow River, near Carseland Alberta. Contractor adherence to the contract special provisions, specifically those directly related to the Migratory Bird Act, was critical to project success. Dillon worked closely with Alberta Transportation to develop contract special provisions that mitigated risk to the owner.
The initial scope of work on this five span precast LF girder bridge included replacing the wearing surface with fibre-reinforced high performance concrete, replacing the expansion joints, approach paving, and maintenance to the bearings. Due to the nature of LF girders, supplemental lateral Dwydag bars were previously added to the superstructure to minimize differential movement between the girders. During preliminary engineering Dillon determined additional restraints were required to minimize the differential movement. Dillon’s scope was increased to include the design of underslung diaphragms.
Carmangay Bridge BF73637
BF73637 was built in 1987 to carry Highway 23 across the Little Bow River. The single span precast DBT girders support two vehicle lanes. The rehabilitation work at this bridge will include replacement of the hot rubberized membrane and ACP, and approach paving. Additional maintenance activities will include miscellaneous concrete repairs, and upgrading the approach guard rails. This bridge rehabilitation is scheduled for construction in 2019.
Willow Creek BF72533N
Built in 1991 this three span concrete girder structure carries Highway 2 northbound over Willow Creek. The proposed work for this structure includes deck rehabilitation, FR HPC overlay, deck joint replacement and approach paving, and upgrading the approach guard rails. This bridge rehabilitation is scheduled for construction in 2019.
INID Canal BF72535N
Located immediately north of BF72533N, the rehabilitation work at this bridge will include FR HPC overlay, deck joint replacement and approach paving. Miscellaneous concrete repairs and approach guard rail upgrades will be included in the work. This bridge rehabilitation is scheduled for construction in 2019.
Built in 1986 BF76410 is a four span structure carrying Highway 36 over the SMRID Canal. The scope of work includes replacing the ACP wearing surface, and upgrading the approach guard rails. This bridge rehabilitation is scheduled for construction in 2019.