how hard to dig 50 feet underground

[Mercedes Benzene]

Originally Posted by Moontanman

Maybe it's a giant end of the world shelter?

I've always wanted to build one of those.

Anyway, if you're looking to dig a big hole, look no further than the current construction site of the Chicago Spire. They're pretty good at the whole hole thing.

[GAHD]

Good, Fast, Cheap. Pick two. If you've luck you'll get them both.

That is your mantra for anything construction related.

If you want a "perfect" hole "fast" you can do it "expensively" By using a half dozen front-end loaders, some back hoes, an army of dumptrucks, and dynomite. See "strip" or "pit" mining practices.

If you want an "allright" hole "fast", you can do it "cheap" with just the dynomite and a few BIG dozers.

if you want a "perfect" hole "cheap" you'll "eventually" get there using human muscle: Is the local penal colony hireing out gangs with picks and shovels? Got buddies who are bored and will do anything for a case of booze? See the low-lifes hanging around the temp-agency looking for tonights party cash? There's NOTHING cheap muscle power can't do, given time.

[DFINITLYDISTRUBD]

If you want an "allright" hole "fast", you can do it "cheap" with just the dynomite and a few BIG dozers.

You forgot to mention...and if you want to have lots of FUN I love esplosions (but then doesn't everybody)

if you want a "perfect" hole "cheap" you'll "eventually" get there using human muscle: Is the local penal colony hireing out gangs with picks and shovels? Got buddies who are bored and will do anything for a case of booze? See the low-lifes hanging around the temp-agency looking for tonights party cash? There's NOTHING cheap muscle power can't do, given time.

I think eventually is the key word here especially using "temps". Where I work we go through temps like they're goin out of style...why?
Because most of them have extremely sucky work ethics and have to have a baby-sitter to make sure that they are doing their jobs.

[C1ay]

These people might have an idea....

[Mercedes Benzene]

Where's Buffy?
She'll tell you how to make a REALLY BIG hole. Big enough, in fact, to swallow an entire city. It's pretty easy. [See Sunnydale for reference]

[modest]

Originally Posted by Mercedes Benzene

Where's Buffy?
She'll tell you how to make a REALLY BIG hole. Big enough, in fact, to swallow an entire city. It's pretty easy.

Easy was it? Trying to remember... There may have been a couple deaths involved

~modest

[binabik]

ok, let me respond to everyone...

Montanaman, i don't know exactly the conditions and i have no expierience in this.

Thunderbird, explosives are fine, though i would want professional ones, and i would want to be more than 100 feet back behind a truck since something 300-400 feet up can move farther than that and if not more than 100 feet i would want to be under the truck instead of behind it.

thebigdog i am actually building a survivalist/minimalist community in my head with no schooling, just an idea i like and i don't really want to list details right now but the buildings will be underground about 5 feet that way i can get 5 stories underground and out of the radiation, i would have gone with the 28 stories of stargate command but that seemed like way too expensive.

zythryn, see i don't know exactly what to consider that is why i am on this forum asking

dfinitlydisturbd, i don't think i want to do a drag line but seeing as i believe for a slightly bigger hole that that i think i can get 2000 or so people fit in with a very small residence, it would be 20x20x10 feet apartments and stacked 20x20x5 so. also since this will be a permenant community i think whatever i do purchase would probably be purchased permenantly so i can expand with the same method. i also thought of a method where i would use a 24 foot diameter Tunnel Boreing Machine and use that to build large expansive of tunnels.

montanaman you are close though it is also going to be more like a modern day castle with defensive placements, i am hopeing what i make the structures out and the fact that they are underground would make it so it has protection in the second to worst case scenario if somoene brings for instance artilliary to take me out like in the movie the postman.

mercedes benzene that does seemt o have a preatty big hole from the pictures

gahd well, it would want it to be preatty percise and not too too expensive though, i do not want to use an army of laborers though that just seems like something i wouldn't want to do and plus eventually i might make another hole like this.

c1ay wow, mine is going to be smaller than that buy quite a bit especially on the deep part

last thought, i mentioned the Tunnel Boring Machine and if i did this i would buy it and keep using it.

thanks more discussion is asked for.




would it be easyer to did lots of small 20feet by 20feet by 10 feet holes, though this would be more spread out.

[jab2]

Originally Posted by binabik

thebigdog i am actually building a survivalist/minimalist community in my head with no schooling, just an idea i like and i don't really want to list details right now but the buildings will be underground about 5 feet that way i can get 5 stories underground and out of the radiation, i would have gone with the 28 stories of stargate command but that seemed like way too expensive.

Excuse me for being cynical, but I think you need to think over you "project" a little more.

Radiation?? I hope you are not meaning nuclear radiation, cause if you do, you have missed the bus by a few decades. The nuclear arms race is past, man. The only radiation that is currently or in the near future of danger to humans are the sun's UV radiation and for that sunscreen is sufficient.

But to come back to your original question. Building something like 5 stories underground can use serious money for excavation and construction. Like a previous poster has said, you cannot expect a flimsy wall to hold the earth from outside without collapsing. You will have to have rather thick rebar concrete retained walls. Then there are the question of water ingress, even if you are above the water table, as you will get water from rain. So you will have to seal the walls. If you are worried about nuclear radiation you are also looking at a serious air supply and filtration system. Then what are you going to do for water and food supplies? For 2000 people you would have to store about 10 000cubic meter (or 10 000 tons) of water per month. And that water will eventually end up as black or grey water, so you have to do something with these. Then there is power supply, for lighting, heating and cooling.

You talk about underground, but then you want defence placements like a castle. These are normally above ground where the defenders can see their attackers and mount a defense, completely negating your "underground protection" goal as you have two choices of manning them. Either seal your defender permanently out to dye or leave your structure open to NBC agents for everybody to die inside.

"Stargate". "Like in the movie Postman". ??? Me think you watch too much TV and movies. Try and visit a real construction site and learn a bit. What you want would not be as easy as in the movies.

[GAHD]

Originally Posted by binabik

gahd well, it would want it to be preatty percise and not too too expensive...

you just gave up on fast figure out who can run a loader or a hoe for gass money and some booze..they're out there.

Originally Posted by binabik

would it be easyer to (dig) lots of small 20feet by 20feet by 10 feet holes, though this would be more spread out.

digging is digging.

Originally Posted by jab2

Radiation?? I hope you are not meaning nuclear radiation, cause if you do, you have missed the bus by a few decades. The nuclear arms race is past, man. The only radiation that is currently or in the near future of danger to humans are the sun's UV radiation and for that sunscreen is sufficient.

Nuclear war is every bit a reality now as it was 20 years ago; just because you fail to realise there are still people manning "the button" in various countries day in and day out does not mean that they are not there. That is reality, come join it sometime.

Originally Posted by jab2

But to come back to your original question. Building something like 5 stories underground can use serious money for excavation and construction. Like a previous poster has said, you cannot expect a flimsy wall to hold the earth from outside without collapsing.

This is what trussing and cross-bracing is for. No wall need ever be wider than 6" with appropriate buttressing. Given the small cubicle nature of the rooms I don't think you'd need that much support.

*if you had the rooms arranged in a manner othe than 90 degree joints, preassure could be more evenly distributed. A "honeycomb" of 2-4" concrete could very well do it.

Originally Posted by jab2

Then there are the question(s) of water ingress...air supply...water and food...power supply, for lighting, heating and cooling.

Valid points. Any Ideas? SOunds like fruitful grounds for a new thread.

Originally Posted by jab2

Try and visit a real construction site and learn a bit.

oxymoron.

[LaurieAG]

Originally Posted by binabik

first hole is 50 feet deep, 400 feet wide, and 400 feet length.

second hole is 50 feet deep, 400 feet long and 40 feet wide

Hi Binabik,

I worked with geotechnical engineers in the 1980's digging test pits for road building materials. These test or borrow pits were about 100M long, 20M wide, about 10M deep and were dug in extremely weathered sandstone.

The equipment used was one Komatsu (equivalent to a D9) bulldozer with rippers on the back. The operator could dig the hole in the morning and fill it back in in the afternoon after the samples were taken. The time taken just depends on how neat you want the holes.