djevans Posted February 20, 2011 Share Posted February 20, 2011 (edited) I was watching some videos on Youtube, and I found an exploding house that I thought was kinda cool. haha 300 sticks of dynamite!!! How much do you think that would even weigh? What do you guys demolition people normally use to blow up a house? I wonder how much dynamite to blow up a tall building..... Where should I go to learn more about how to become a demolition expert? Edited February 20, 2011 by djevans Link to comment Share on other sites More sharing options...
erid Posted February 20, 2011 Share Posted February 20, 2011 I'm gonna tell you this before you get yelled at by some of the other guys here. This isn't the place to be to learn about High Explosives, bombs, or anything like that. We make fireworks for entertainment, not to blow anything up. I'd go somewhere else to learn to be a demolition expert, but don't jump right into high explosives, they are extremely dangerous. Link to comment Share on other sites More sharing options...
NightHawkInLight Posted February 21, 2011 Share Posted February 21, 2011 Sorry to disappoint you, but they would never demolish a house with explosives other than for a tv show. I would say that was 2-300lbs of explosive, along with some gasoline for effect. Real demolition is often done with a big ol' front loader. What is sometimes done with explosives are very large buildings which takes months of planning. Just an educated guess, but to get into that I imagine you should study primarily engineering and math. Link to comment Share on other sites More sharing options...
dagabu Posted February 21, 2011 Share Posted February 21, 2011 I have several in-laws the work for VIET, they do demolition for a living and they dont use TNT, in fact they dont use C-4, they use RDX shape charges after stripping the interior out. They also never use explosives on flammable structures. Steel and concrete only. Link to comment Share on other sites More sharing options...
Mumbles Posted February 21, 2011 Share Posted February 21, 2011 For training for demolitions, you'll probably want to look into a mining school. Some have demolition programs. There is quite a lot of engineering that goes into it. Link to comment Share on other sites More sharing options...
oldguy Posted February 21, 2011 Share Posted February 21, 2011 (edited) This is what you use for demolishing wooden type structures, not explosives. The video you posted was made just for special effects. Otherwise to put on a loud flashy circus act for TV show spectators. Just as NightHawk & Dagabu states, you don't use explosives to demolish wooden structures. It is not cost effective from a business or insurance perspective and can lead to very unexpected results including debris flying long distances. It would be far cheaper & much safer to just burn it down, or demolish it with an excavator. I have used explosives & shape charges to take down a fair number of buildings, bridges, silo's, etc. You don't want a structure to violently explode as that video shows. You want it to as quietly as possible implode, or otherwise fall in on itself be taking out its main internal supports with the least amount of explosives possible. Basically it's a matter of reverse engineering. Take out what holds it up at precise points, it falls down. If it's multi-story, with millisecond delays you start in the center & work in a circle so the center falls down & the walls fall inward. You want inertia & gravity to do most of the work, rather than explosives. Explosives just get the ball rolling. The tricky ones are where you don't have good blueprints of how the building was constructed. You have to do a lot of drilling in concrete to find the steel beams. Ones with multi story parking lot type basements are the best. That gives you a lot of sub-surface open space with most supports exposed. Plus a hole to fill as the building comes down. Edited February 21, 2011 by oldguy Link to comment Share on other sites More sharing options...
Chuleo Posted February 21, 2011 Share Posted February 21, 2011 ...that video is retarded! Blasting up things safely is hard work with a lot of mathematics and engineering. If you really like to become a demolish expert you'll have a long and heavy way to go and in the end it won't be that of a fun anymore when you see behind the scene. And blasting things up isn't as spectacular as shown in this video. Link to comment Share on other sites More sharing options...
djevans Posted February 21, 2011 Author Share Posted February 21, 2011 Isn't RDX used in c4? Link to comment Share on other sites More sharing options...
dagabu Posted February 21, 2011 Share Posted February 21, 2011 Yes, with common amount of 91% or so in the mix where RDX in a solid state with no other limiters or plasticizers has a relative effective factor of 1.82 vs 1.73 for C-4. Link to comment Share on other sites More sharing options...
dagabu Posted February 21, 2011 Share Posted February 21, 2011 ...that video is retarded! Blasting up things safely is hard work with a lot of mathematics and engineering. If you really like to become a demolish expert you'll have a long and heavy way to go and in the end it won't be that of a fun anymore when you see behind the scene. And blasting things up isn't as spectacular as shown in this video. I disagree, the video was a lot of fun and I am sure that they did their homework as they lifted the whole roof mostly intact. I still framed the video to the frame where it all was under the overpressure, that was cool! Link to comment Share on other sites More sharing options...
Copperheadi69 Posted February 22, 2011 Share Posted February 22, 2011 Looks like a waste of good explosives - you could get the same results with just a few sticks of explosive and 2 to3 5 Gallon cans of gasoline - Improvised FAEYES only on TV - something to boost the ratings Link to comment Share on other sites More sharing options...
Recommended Posts