Originally posted by Condorcet
There's no way the massive amount of material excavated to build subway tunnels can just disappear into surrounding "cracks and fissures" as magma.
There's way too much material to move. Also consider the lethal gases released by creating that amount of magma, they'd have to be vented
somewhere.
If the Subterrene existed it would be used to build federal-funded subways in our large cities and to build tunnels for roads and conventional
railways. Why waste time and money on less efficient tunneling methods if they have this technology? Why didn't they use the Subterrene for the
Yucca Mountain nuclear waste storage facility?
There is no evidence this device exists, and plenty of reasons to believe it doesn't. I've seen the patent for it, but it shows a small drilling
device, not a replacement for the 18~25ft diameter conventional tunnel boring machines.
Are we reading the same patents from the Subterrene wikipedia? They state clearly in the patent that only some of the rock would be used for the liner
and that in certain cases, they would thermally stress fracture rock for "mechanical removal" suggesting they might back it up and bring in a bucket
loader or something.
The face would get hot, but in the diagrams, it clearly shows a cooling system(plus an alternate) for solidifying the walls of the tunnel. Of course
it'd be hot and toxic for someone not wearing proper attire much like a vulcanologist might wear along with a respirator system.
Nuclear power(stigma), toxic gasses and the possible expenses involved might be why it isn't used in the public domain even though part of the reason
for inventing the thing as stated in the patent was to reduce the cost of replacing the cutters on TBMs(among other things) using previously patented
thermal drilling principals.
They also quote a 2-12 meter diameter capability which sounds big enough to me.
I'm not saying this thing exists, but it is the first time I'd seen it mentioned and decided to check out the patent for it which I found
interesting and not entirely impractical.
At any rate, you're probably right and they don't exist, but rather, have only been patented. For all I know, the patent could be expired
already.
On a side note, after watching the DUMB video on the ATS media page, it was clear to me that not all of the images used to compose the video were
really pictures taken in DUMBs. Pretty much the day after seeing it, I watched a discovery channel show about Tokyo's flood control system which is
rather impressive and one of the shots used in the DUMB video was of their hugantic overflow tank.
Link
TUT TUT
