After Thursday's Burlington Skyway crash, how do you determine the structural integrity of a bridge?
According to the latest reports, the Burlington Skyway is closed for at least the long weekend after Thursday afternoon's accident caused part of the bridge support structure to collapse, with no word yet on when it will reopen. After all that, how do you test something that complex to be sure it's safe?
From the pictures posted to social media, by people on the scene, police and news agencies flying overhead, the damage to the Skyway is pretty serious.
Even after they clear away the dump truck that caused the problem and the crushed tractor trailer that fell victim to the incident, engineers from the Ministry of Transportation have quite the job on their hands, especially when they're dealing with a bridge crossed by upwards of 80,000 vehicles every day. The engineers know their stuff, though, and political pressure - as tough as it may be - doesn't enter into it, according to McMaster University civil engineering professor Samir Chidiac.
"When it comes to life safety," he told CBC News, "we don’t mess around."
If there's one benefit to the timing of this accident, it's that the bridge had recently gone though a full inspection, and is currently undergoing maintenance work. With the results of that inspection in hand, it is much easier to go through the damage, to see what structural elements have been affected, and how that affects the overall integrity (not to mention knowing exactly what damage was caused by the accident, as opposed to what may have already been there from before).
It's difficult to test the strength of materials sometimes, especially when you can't simply apply brute force to them to make sure they'll stand up to punishment. So, how does one go about inspecting a complex through-arch bridge will multiple interconnected support structures, to ensure that it's going to stand up to those tens of thousands of vehicles rumbling along it every day, without causing more damage to it and possibly even bringing it down around you?
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