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by kazinator 813 days ago
I think the only reasonable goal would be to design the bridge to minimize damage to it, so that one damaged section doesn't bring down others.

Building a bridge to actually stop the ship is not only infeasible, but it would likely kill (more) people onboard.
1 comments
bobthepanda 813 days ago
the modern practice is layers of defense; in addition to building a bridge that doesn't fail at a single point of failure, you also generally design what's around a bridge pier to stop or at least slow down the ship (by, say, running aground onto a bed of rocks around a pier)
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PeterCorless 813 days ago
For a bridge such defenses are called dolphins.

"A notable example of dolphins used to protect a bridge is the Sunshine Skyway Bridge across the mouth of Tampa Bay. In 1980, the MV Summit Venture hit a pier on one of the bridge's two, two-lane spans causing a 1,200-foot (370 m) section of the bridge to fall into the water, resulting in 35 deaths. When a replacement span was designed, a top priority was to prevent ships from colliding with the new bridge..."

Source: https://en.wikipedia.org/wiki/Dolphin_(structure)

The MV Summit Venture was a 33,900 deadweight tonnage ship. MV Dali was a gross tonnage of 95,128. Nearly 3× as large. It's questionable whether dolphins would have totally prevented such a tragedy.

Yet similarly, expect dolphins to be brought up as a key component of resiliency for any designed replacement bridge.

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bobthepanda 813 days ago
That's also a thing.

But note how the main bridge piers are on giant islands much larger than the pier itself: https://en.wikipedia.org/wiki/Dolphin_(structure)#/media/Fil...

If you really want to make it unblockable you build a bridge+tunnel. https://en.wikipedia.org/wiki/Bridge%E2%80%93tunnel

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js2 813 days ago
The CBBT is downstream of the bridge which collapsed. I've driven it many times.

https://en.wikipedia.org/wiki/Chesapeake_Bay_Bridge–Tunnel

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KWxIUElW8Xt0tD9 813 days ago
It has tunnels because the Navy did not want the bay blocked if the bridge dropped into the water. Which is exactly what has happened in Baltimore.
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