Posted on 04/02/2013 10:48:09 PM PDT by zeestephen
The world's widest tunnel boring machine arrived in Seattle in pieces Tuesday aboard a ship from Japan. It will be reassembled in a pit to begin the year-long dig to create a two-mile tunnel under downtown Seattle.
(Excerpt) Read more at nbcnews.com ...
No, it's because the graboids can only burrow thru dirt and sand, not rocks........Sheesh, everybody knows that.
What is that? The "Swiss Army Knife" approach to earth moving?
LOL! It does look like one doesn't it?
what kind of insanity digs a huge tunnel under a city deliberately??????????????
It’s not really an earth mover...bucket-wheel excavator for coal strip mining.
Agree - tunnels are not earthquake proof.
However, the Viaduct is 60 years old, double decked, and threatens to pancake everything on the first tier and at street level, like those horrible photos from Oakland and Japan from about 20 years ago.
Above ground construction is much cheaper, but the Viaduct and I-5 are downtown Seattle eyesores and severe noise polluters.
Please don’t ban me from Free Republic, but I actually voted for the much more expensive tunnel.
I was talking with a tunnel expert just the other day. He said that tunnels hold up very well under earthquakes. He was at one for repairs after a fault ruptured right through the tunnel. Offset the tunnel by 3 or 4 feet, but the damage was confined to just the area (+/- 20’) where the fault sliced through it! That surprised me.
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