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green beret
June 12th, 2002, 11:23 PM
I have a copy of the explosives and demolitions manual (US Army) but it only covers the demolition of bridges. I know a bit about building demolition but I would like a manual, could anyone help me please?

Omogen
June 13th, 2002, 04:32 PM
hmmmmmm not a good post if "big brother" is watching...check out the forum

(Green Beret has been "checking out" the Forum for a lot longer than you, Omogen. - Mr Cool)

<small>[ August 05, 2002, 03:58 PM: Message edited by: Mr Cool ]</small>

Magas
June 17th, 2002, 09:03 AM
GB
there is some of the information you want in " Explosives for Australian Engineers by C.E. Gregory University of QLD press. One of my old texbooks

phreak
July 29th, 2002, 11:01 PM
I don't know about any manual but I do know one thing that when doing demolition on a building you put in on the foundation. you blow the building foundation the building calopses or just gets blown up if the explosive is powerful enough and thats that. usually you would strap the explosives on all sides so that the building wouldn't just blow on one side.

Eliteforum
July 29th, 2002, 11:11 PM
I remember seeing a book on the FTP about blasting. Blasting Manual I think it was called. Something alone those lines, PDF format, so check the PDF folder for starters.

megalomania
July 30th, 2002, 02:37 AM
That may be a gross oversimplification of the facts, phreak. I imagine there is a considerable amount of detail in the proper placement, and certainly the amount, of explosives to be considered. Under your analogy one could use a string of firecrackers to qualify for explosives around all sides. This is exactly why a book written by the experts is so useful.

Mick
August 1st, 2002, 01:43 PM
the best explosive placement for building demolition would not be on the sides, or in the foundations.

you start in the center, and work your way out. leaving the sides intact when the charges go off.

look at it like this

1 2 3 4 5 6 7
| | | | | | |

lets pretend this is a building, 1 and 7 represent the sides, and 2,3,4,5,6 represent the inside support columns.
if you put your explosive on 1 and 7 then 2,3,4,5,6 will still be left standing thus your building will be fucked up, because the support columns will be damaged and weakened and the building could fall any direction - not safe, messy, and down right pain in the ass if it doesn't fall over at all. and above all, anything within 1km is going to be showered with bits of debris.

if you place your explosives on 3,4,5 then the center of the build will collapse on top of itself, pulling 1,2,6,7 down with it.
and because you haven't broken the outside walls when the charges go off debris will mostly stay contained.

thats my take of it anyways - it seems pretty common sense, so i would imagine it would work. obviously this extremely dumbed down, and a hell of alot more planning and work would go into it.

however, if you were planning a "terrorist style" demolition(which is bad, and i know that you would never ever ever in a million years do something like that - obviously any further discussion on this is 100% theoretical)
then you would of cause aim for the center of the building once again.
pretty much all buildings in the last 60 odd years use the center of the building as its main support, and only use the outside frame to hold the skin on.(think of it like the human body. if you shoot someone in the ass - ouch it hurts, but they can still function. shoot them in the spine - there fucked.)

another way you could look at it is the WTC. the only reason they fell down is because the main structural support was in the center. when the planes crashed set the place alight with AV gas, the center column heated up, weakened and then collapsed - bringing the rest down like dominos.

anyways, i'm tired and i think i've typed to much. going to bed.

<small>[ August 01, 2002, 12:45 PM: Message edited by: Mick ]</small>

kingspaz
August 1st, 2002, 08:18 PM
for soft target, small scale demolitions such as american homes (wooden framed stuff), would a FAE be more effective (if initiated from the centre) as opposed to a conventional charge?

Mick
August 2nd, 2002, 02:37 PM
i would imagine blowing up a house would be quite hard, assuming of course you were trying to do professionaly. i don't know how you would it with out lauching bricks and roof tiles etc all over the place and into neighbouring houses.

however if it was a "hit" type thing, then the way i would do it would be to calculate the volume of the house, then calculate a LPG to air ratio(i suggest LPG cause its cheap as chips, and extremly common), and then fill gas tanks with the requied amounts and place them thru out the house, along with an ignition device in the center.
(dunno if this would work..but it sounds pretty good. i'd probably throw some fans in aswell to make sure the fuel/air mixxed well)

however, your really only wanting or needing to distroy one target and if you use a FAE then your going to do shit loads of damage to other innocent property around the target. so again, you end up with a pretty messy outcome.

they best way i've seen a house demolished(unfortunatly it didn't involve explosvies) was with a D9 bulldozer. the guy just drove over the house about 5 times, then picked up the majority of the house in 3 scoops and put it in a large waste bin. 20 minutes and the house was gone.

J.T.Ripper
August 4th, 2002, 03:58 AM
I'm not sure about the house demolition but when taking down support columns you'll want to use sand bags around the explosives so it forces all the power inwards. Sorta like a giant shaped charge.

===??| |??===
===??| |??===
===??| |??===

= sand-bags
?explosives
| | support column

Now if you want to take the building down messy. Don't use much explosives, just fill a couple of vans with something like ANFO (A couple of vans of ANFO is a shitload of explosives. - Mr Cool), and park them in one corner of the underground car park. The building will crumble to one side. and probebly take out the building next to it.

<small>[ August 04, 2002, 04:46 PM: Message edited by: Mr Cool ]</small>

kingspaz
August 4th, 2002, 10:36 AM
if its big enough to have an underground car park then its likely big enough to have the main support column in the centre.this would mean the corners would be destroyed but the building would not fall. also shaped charges do not work by forcing the explosive inwards. they work by collapsing the cone into a jet of metallic plasma which pushes aside anything infront of it.

<small>[ August 04, 2002, 09:37 AM: Message edited by: kingspaz ]</small>

zaibatsu
August 4th, 2002, 02:27 PM
Yes, what Ripper is describing is a tamped charge, not a shaped one.

J.T.Ripper
August 5th, 2002, 03:26 AM
I would just like to know what you want this type of info is for.
Should I warn people i know that work in large buildings, or is it just for the sake of knowing it.

And what do you want to happen, do you want the building in a neat pile in its own size or do you want it to fall down the street it over looks. (the later been the easier to achive)

kingspaz
August 5th, 2002, 08:19 AM
Ripper, all discussion is theoretical. this is NOT a terrorist organisation and does NOT support terrorism in anyway.

J.T.Ripper
August 5th, 2002, 08:53 AM
I know that this site is all "theoretical". But im just asking because for all I know is we could be helping a guy blow up a building some where as a terrorist act. Or on the other hand we could just be helping someone who is writing a thriller book that wants acurate data. im just interested in the motives behind such a question.

xoo1246
August 5th, 2002, 09:14 AM
This is a forum where we discuss explosives. A terrorist could use explosives to destroy a house, so could an engineer. He might not have any other motives but curiosity, the discussion is theoretical.
Some also discuss the making of very potent poisons, that doesn't worry you, but this do?
You seem a bit paranoid.

<small>[ August 05, 2002, 01:11 PM: Message edited by: xoo1246 ]</small>

Mick
August 5th, 2002, 02:25 PM
i have to say, that could be the single most stupidest question i have ever heard on this board:
"I would just like to know what you want this type of info is for.
Should I warn people i know that work in large buildings, or is it just for the sake of knowing it."

what do you expect him to say?
"yes ripper. i plan on blowing up a large building"

obviously a board of this nature is totaly theoretical. - everyone here is looking for accurate data because there writing thriller novel.

wake up.

<small>[ August 05, 2002, 01:25 PM: Message edited by: Mick ]</small>

nbk2000
August 5th, 2002, 04:54 PM
If a person using the hanle "J.T. Ripper" (Jack The Ripper) asked us about knives, do you think anyone here would ask:

"You're not planning on gutting any whores are you? Because we don't want to help any potential serial killer!"

:rolleyes:

Whatever.

Besides which, a "terrorist" wouldn't need to ask us for advice since they have government sponsors and trained engineering experts of their own to consult with. They don't need to ask a bunch of hobbyists who fiddle around with gram quantities of explosives how to demolish a building that would require TONS.

Ctrl_C
August 5th, 2002, 06:48 PM
Mick, I have to disagree about the WTC. The WTC was a radical design in which the outside was the main support. When the planes hit, they damaged this and also once the floors started collapsing inside, the four outer load bearing walls were able to buckle. This is evident in the fact that they found the brackets used to hold the floors to the outer walls were badly misshapen and warped from the intense heat and strain.