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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)



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.


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


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

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


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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