January 13, 2016 by On-Site Magazine
The recently opened cable-stayed Nipigon River Bridge in northwestern Ontario is operating with only one lane after a expansion joint gave way during a winter storm this week.
Part of the steel decking of the bridge lifted almost 60 centimetres on January 10, reportedly during very high winds. No-one was injured but the crossing was closed for almost a day, which severed the Trans-Canada Highway and “cut Canada in half,” said a local politician.
The $106-million project is still under construction and has earned a high profile as Ontario’s first cable-stayed bridge.
Ontario’s Transportation Minister, Steven Del Duca, was due to head up to the area today (Jan 13) to review the situation
Initially reports suggested that the cold temperatures had caused an expansion joint to fail, and that a gust of wind had lifted the deck from its base.
Ontario Northern Development and Mines Minister Michael Gravelle told CTV News, “Apparently the bolt that holds the girders in place, which keeps the bridge level, broke in some fashion and that lifted the bridge up.”
Crews have since relevelled the bridge temporarily using the weight of 110 highway barriers. That allowed a single lane to be reopened to traffic in both directions, but only for cars and regular weight trucks.
Gerry Chaput, the ministry’s assistant deputy for provincial highways, told CBC News the broken bolts will be subjected to special testing.
“We’ll take the bolts that broke, we’ll take them into a laboratory. We’ll check the grade of the steel,” he said.
“We’ll try breaking a few of them ourselves to see what load they break under. We’ll look at the structure from a computer-modelling perspective to understand what the loads were to determine what might have played a role in causing them to break.”
Chaput said similar bolts are holding together another section of the bridge — and all the bolts were fully inspected before the bridge was re-opened.
The crossing is on Highway 11 located near the municipality of Greenstone, about 250 kilometres northeast of Thunder Bay. It links Ontario to western Canada and carries around 1,300 trucks a day carrying goods worth $100 million. When the bridge was closed trucks were diverted through Sault Ste. Marie and the United States.
Construction on the bridge started in the summer of 2013. The westbound side was opened to two-lane traffic in November last year and completion is set for 2017. It has three towers rising 70 metres above the river, and a main span 139 metres long.
The design and build team included engineers Hatch Mott MacDonald and McCormick Rankin, and general contractor Bot Construction.
Here is a drone video of the construction site that was shot in fall 2015
Click here for a graphic representation of how a cable-stayed bridge is built.