ST-JACQUES BRIDGE SOARS
Designed to evoke plane in flight
If you’ve noticed the large white spire soaring above the almost finished St-Jacques Bridge in western N.D.G., you’ve made the designers happy, because that was the idea.
One of three distinctive overpasses of the $3.67-billion Turcot reconstruction project meant to highlight entryways to Montreal, the look of the new St-Jacques Bridge, with steel cables splaying like wings from the central tower, is meant to evoke the form of an airplane.
“It’s one of the signature bridges that were planned for when the Turcot was being designed,” said Martin Girard, head of communications for Transport Quebec. The structure will be easily visible by commuters on the Highway 15 southbound, and particularly distinctive for those using Highway 15 northbound and merging onto the Décarie Expressway.
The other two signature bridges are the span at Ste-Anne-de-Bellevue Blvd., near Angrignon Blvd., crossing over Highway 20, and the Lachine Canal overpass, which will feature a cable-stayed design similar to the St-Jacques Bridge.
The St-Jacques Bridge spire is 55 metres high, roughly the height of a 15-storey building, and was erected in one day on Aug. 26, with the help of a 650-tonne crane. It was built in Quebec City in three sections that weigh 14, 40 and 50 tonnes.
The “design touch” helps to give the 2,100-tonne bridge a sense of lightness, while the 10 cables anchored to the bridge provide structural support, Transport Quebec notes in its description.
While it is not quite as high as Montreal’s largest tower — the 165-metre one belonging to the Olympic Stadium — the St-Jacques spire still tops the one on the Papineau-Leblanc Bridge on Highway 19 (38 metres) and the one on the Olivier-Charbonneau Bridge, on Highway 25 (48 metres).
The St-Jacques Bridge, which spans six lanes of the Décarie Expressway and is 120 metres long, is supposed to reopen at the end of 2018. Before it was demolished, it was estimated 20,000 people a day used it, but that number could rise now that the McGill University Hospital Centre has been constructed next door.
Once the entire Turcot project is completed by the end of 2020, drivers coming from downtown will be able to exit off of the Ville Marie Expressway westbound and onto St-Jacques St. again for the first time in five years. Motorists headed toward the central city will be able to continue on St-Jacques St. all the way downtown as of December.
When the Turcot is finished, they will be able to merge onto the Ville Marie Expressway slightly east of the MUHC superhospital at Pullman St.
Originally scheduled to be rebuilt by 2015, before work on the Turcot Interchange began, the StJacques Bridge reconstruction was delayed by three years because it turned out the massive St-Pierre sewage-water collector located below it also had to be rebuilt.
Located 30 metres beneath StJacques St. and measuring 10 feet wide and 12 feet high, the sewer pipe was built in 1930 and serves 144,000 households. It was so deteriorated that reinforcement repairs were no longer sufficient to keep it working.
The bridge was demolished over the space of three weekends in July 2016. To rebuild it, the CanamBridges corporation constructed five steel girder boxes at their plant in Quebec City and transported them to Montreal.
Three of the girders were pushed very slowly — moving half a metre every six minutes — using a system of hydraulic lifts and rails over the Décarie Expressway in May, and the bridge deck was slid onto the girders, all of them resting on a central pillar. The remaining girder boxes and bridge deck were added in June, and the spire in late August. Thirty pre-fabricated steel deck plates were laid onto the bridge girder structure to form the deck.
The total cost of the bridge was pegged at $85 million in April, which includes work on the StPierre collector and extra costs related to working in conjunction with the Turcot project.