The Chesapeake Bay Bridge-Tunnel turned 40 a few years ago, and its age is starting to show. The roadway is held aloft by nearly 3000 massive concrete pilings, which extend on average 100 feet to the bottom of the bay. They’re starting to crack, which means the steel columns inside are being exposed to corrosive seawater.
But how in the world do you pour new concrete underwater? The answer can be seen in this video. (Hint: It involves diving gear and a massive zinc “sleeve.”)
The most interesting part of the repair process, though, is how the damaged pilings are turned into a giant low-power battery to stave off further corrosion.
An aside: There’s a funny line in there about how the bridge is so big “it can be seen by satellite.” At this point, isn’t a hamster big enough to be seen by satellite?
May 19th, 2009 at 5:25 pm
Your new site looks very interesting. (I added a link to my blog) I’m a fan of the entertaining breezy writing style.
I will show the underwater concrete pour to my class!
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November 8th, 2009 at 5:24 pm
This is very much what I was looking for while writing a semester report on under water concrete design and usage for my Materials class at StMartin University. Chesapeake Bay Bridge-Tunnel retro fits Thanks Anita Torres