Canadian authorities tried to reassure the general public concerning the security of bridges within the nation following the collapse of a bridge in Baltimore, Md., early Tuesday morning after it was rammed by a container ship.
Halifax Harbour Bridges, which operates the 2 spans throughout the harbour between Halifax and Dartmouth, stated it has taken steps to mitigate the dangers of collisions between ships and bridges. The Crown company says it’s notified by the port authority each time a business vessel is scheduled to go beneath the spans.
“Bridge patrol workers present bodily lookouts on the bridges as ships go, and a posh sequence of cameras monitor and report the transit,” the company stated in a information launch.
As effectively, rock islands constructed across the piers of the bridges in 1983 provide additional safety, Halifax Harbour Bridges stated.
Rock islands or different protecting constructions seem to have been lacking from the piers of Francis Scott Key Bridge in Baltimore, stated Bruno Massicotte, an engineering professor at Polytechnique Montréal.
The bridge was struck round 1:30 a.m. by a container ship that misplaced energy and rammed into one of many piers, sending automobiles plunging into the water. Six individuals are lacking and presumed useless.
Pier safety
Massicotte stated he’s stunned that the bridge’s piers weren’t protected to soak up the vitality from a potential ship strike.
“When you may have a bridge pier within the waterway, it needs to be protected towards ship impacts,” Massicotte stated in an interview Tuesday.
The simplest approach to try this is to encompass a pier with concrete, metal or rocks, which may all take up the vitality from a possible strike and block a vessel from hitting the bridge itself, he stated. Canada’s bridge code requires piers to be equally protected if they’re thought-about to be susceptible to ship strikes.
“A bridge pier will not be designed to withstand that type of affect, in order that’s why we put issues within the water,” he stated.
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Quebec’s Transport Division, which is accountable for a number of bridges spanning the St. Lawrence River, stated it has protected the piers of the one bridge underneath its jurisdiction that has been judged liable to being struck by business ships.
That bridge, the Laviolette Bridge connecting Trois-Rivières, Que., to Bécancour, Que., is constructed from the identical materials because the span that collapsed in Baltimore, division spokesman Louis-André Bertrand stated in an electronic mail.
In 1986, Bertrand stated, the division performed “huge” work to create protecting islands across the bridge’s piers.
“Consequently, if a ship approaches one of many basis items, will probably be stopped by the granular materials across the pier and won’t be able to achieve it,” he wrote, including that in 1992 a ship ran aground close to the bridge with out inflicting any injury to the construction.
Most different giant bridges over the St. Lawrence River don’t have piers situated in transport lanes, he stated.
In British Columbia, the Ministry of Transportation and Infrastructure stated plans are within the design stage to guard the Lions Gate Bridge and Ironworkers Memorial Bridge, each of which join Vancouver to neighbouring suburbs, from ship collisions.
“We’re enhancing the prevailing concrete collar on the base of the south tower of the Lions Gate Bridge with an in-water rock-fill berm,” the ministry stated in an emailed assertion. “The north tower already has one. We may even be putting in in-water deflection constructions on the Ironworkers Memorial Bridge.”
Elena Dragomirescu, an engineering professor on the College of Ottawa, stated any bridge, no matter its age, might collapse whether it is struck by a big cargo ship. “Bridges want all of the elements to work collectively. If one of many elements is broken, or collapsed on this case, then your entire bridge is in danger,” she stated in an interview Tuesday.
However it’s uncommon that bridges collapse as a result of they’re struck by ships, she stated. Dragomirescu stated she’s extra apprehensive concerning the structural integrity of decaying spans throughout Canada that might come down due to poor upkeep — like in 2006 in Laval, Que., when a freeway overpass collapsed and killed 5 folks.
— With information from The Related Press.
Characteristic picture: Boats work close to wreckage of the Francis Scott Key Bridge on Wednesday, March 27, 2024, in Baltimore, Md. Restoration efforts resumed Wednesday for the development employees who’re presumed useless after the cargo ship hit a pillar of the bridge, inflicting the construction to break down. (AP Photograph/Matt Rourke)
