Senator Sid Buckwold Bridge Rehabilitation

Senator Sid Buckwold Bridge, also known as Idylwyld Freeway Bridge, was built in 1966. This 3-Span reinforced concrete bridge connects one of the main arterial roads to the heart of the City of Saskatoon, serving more than 45,000 vehicles per day. By crossing the South Saskatchewan River, the bridge also connects Highway No. 11, one of the major provincial highways that span from Regina to Prince Albert. The bridge replaced the City’s first railway bridge that was built in 1890. The surrounding area has seen substantial change since then, such as the River Landing development.

The main bridge structure is 183m long. It consists of both precast and cast-in-place post-tensioned girders. The two ramps connected to the main structure have undergone major rehabilitation in the past. This was the most intensive rehabilitation the main structure has seen to date that will extend the useful life of the bridge well into the future. The investigations to determine the extent of the rehabilitation required for this 53-year old structure exposed very unique situations that needed to be addressed.

Initial load rating that was conducted using conventional live load distribution factors indicated that the exterior girders were in dire need of shear strengthening. Critical thinking of the design team led to conducting a load test to determine the actual live load distribution factors. It was then found only 36.6% of the load was acting on the exterior girders, instead of the initial assumption of 91.9%, ultimately saving the City $2M in strengthening work. In addition, post-tensioning cables were evaluated using a combination of impact-echo and destructive visual inspections. The spread footing pier foundations were inspected with Side-Scan Sonar along with a Bathymetric Survey.

During the evaluations, it was found that the dead load acting on the bridge was substantially increased by pigeon droppings. The access to girder cavities has been accessible to pigeons since the time the bridge was built. During the rehab, approximately 1850 birds were euthanized and over 1,100 cubic metres of pigeon feces removed, which became an interesting source of social media buzz.

With the completion of partial depth deck rehabilitation, replacement of expansion joints, installation of galvanic protection systems and other repairs, the 53-year old bridge was given another 50+ years to serve the citizens of Saskatoon.

Acknowledgements: City of Saskatoon, Allan Construction

Author

Heendeniya, Udara

Titre de la séance

Transportation Structures

Catégorie

Conception et gestion ouvrages d’art

Year

2021

Format

Paper

File

 


Merci à nos commanditaires premier