The 5.6 kilometer-long Highway 11, Noden Causeway, which crosses Rainy Lake near Fort Frances, Ontario, includes three in-water concrete girder bridge structures supported by 61 piers with a total of 1,125 steel tube piles.
Installing threaded shear studs above and below water level along with reinforcing cage around the pile.
This project, which was carried out over a three-year period, involved the polymer encapsulation of the piles, which had suffered heavy pitting and steel section loss due to the effects of a severe form of microbiologically influenced corrosion. Dominion Divers worked with George Armstrong Co. Ltd., a general contractor from Fort Frances, to complete the work on time and in budget.
This demonstrates Dominion Divers expertise in inspecting and repairing bridges of different types of construction, working in deeper depths, and working mid-water.
The inspection crew was required to inspect, measure and catalogue every pile in order to get repair jackets of the correct lengths fabricated and were also required to submit clear video inspection reports to the owner for every pile between each step of the repair process.
The repair design called for reinforcing the existing pile and incorporating both an epoxy adhesive and mechanical (shear stud) bond between the existing pile and the encapsulation. All the in-water pile work, totaling approximately 8,000 hours of bottom time, was carried out by Dominion Divers.
Typical pile bent with completed repairs.
The repair of each pile consisted of the following steps:
- Protecting the work area and the marine environment with turbidity barriers.
- Protecting the worksite and managing marine traffic in a busy waterway.
- Locating, marking, and protecting underwater fiber optics cables from physical harm.
- Manual scraping and removing the organic scale crust from the pile below water.
- Water blasting the steel piles above and below water level, using a 40,000 psi pump and lances with rotating fan-tip nozzles.
- Installing threaded shear studs above and below water level.
- Installing a reinforcing cage around the pile and tack welding to secure in place.
- Water blasting the entire encapsulation area prior to jacketing to ensure a good bond.
- Installing the translucent FRP jacket and closing with screws and gaskets.
- Pumping the annular space with the epoxy grout.
- Backfilling the base of the piles and cleaning up all debris.
Barges encompassing the pier.
During the course of the project our team installed over 60,000 shear studs under water using the Ramset Salvage Master high velocity powder actuated tool. This was the most product ever used on a construction project anywhere in the world, at times straining the production capacity at the manufacturing facility in Australia.
As with all our projects quality was assured by our QA/QM procedures, and by submitting inspection reports and video files for verification by the owner’s representative in a timely fashion, and before proceeding to the next step.