Get more dolphins

Engineers say yeah that’s what happens.

To bridge experts, the collapse of Baltimore’s Francis Scott Key Bridge after being hit by a heavy cargo ship was as inevitable as it was devastating.

When a vessel as heavy as the Singapore-flagged Dali collides with such force against one of the span’s supercolumns, or piers, the result is the type of catastrophic, and heartbreaking, chain reaction that took place early Tuesday.

So maybe take all possible measures to keep that from happening? If you have a setup where massive container ships regularly go toddling under bridges, you’re gonna wanna make sure they don’t go oops on the way through.

No bridge pier could withstand being hit by a ship the size of the Dali, said Benjamin W. Schafer, a professor of civil and systems engineering at Johns Hopkins University. “These container ships are so huge,” Schafer said. “That main span has two supports. You can’t take one away.”

Those ships have grown and grown and grown. Remember the one that got stuck across the Suez canal, blocking shipping for days and days and days? It’s one of the new massive type.

Ian Firth, a British structural engineer and bridge designer, reviewed video footage and said there appeared to be at least two protective objects in the water next to the Key Bridge. The objects, known as “dolphins,” are supposed to protect maritime structures from being hit by vessels. But Dali, the container ship that struck the bridge, appeared to have come in “at an angle,” Firth said, which means the devices were unable to prevent the ship from striking the bridge, sending part of it tumbling into the water.

If the Dali had been traveling straight on instead of at an angle, Firth said, it probably would have hit the protective objects. And if there had been three or four vessel-protection objects around the bridge, the outcome might have been different, Firth said, adding that he expects lessons will be learned from Tuesday’s tragedy.

Firth noted that the bridge, which was built in 1977, was erected at a time when ships were not as big as they are now and the flow of traffic was not as busy. These days, structures are designed with better protective measures in place, he said, though he noted that even a brand-new bridge would have “come down in the same way” if it were hit by such a large vessel traveling at speed.

So make sure they don’t do that.

I’m wondering about the role of tugboats. One of their purposes is to keep larger vessels from crashing into things.

Schafer, who said he used to teach about the bridge in his Johns Hopkins classes since it was “one of the signature bridges of Baltimore,” called the collision “a huge infrastructure failure,” but not because of the bridge collapse. He said the shipping industry needs systems to keep a ship on track when it loses power.

Why yes. Fork out for some tugboat assistance when you have bridges to go under.

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