high-rise demolition

Rumor has it that high-rise demolition is accomplished by a series of successive explosions occurring every floor or so, beginning at the top. My question is this: Does the proper technique require that the delay between sucessive explosions increase, decrease, or remain constant, as the process progresses downward? There’s no money at stake here, just an opportunity to show-up my overbearing father-in-law, who regularly opines on matters he knows nothing about with nearly the same frequency that others draw fresh breath. Anyone out there who actually knows the answer?

TLC or the Discovery Channel runs a program on this every so often - and I thought the timing and delays were part of the tricks of the trades and not shared with outsdiers.

He may have seen the same program, more than once. He might remember more than I do…

The ones I’ve seen on the tube involve exposing the steel supports in the base and blowing them in a sequence that drops the whole building either sraight down or into a selected clear area. I never saw one where they blow each floor.

I watched when they dropped the Hilton Hotel in Hartford it blew from the bottom and dropped straight down.

Lex Non Favet Delicatorum Votis

I’m not sure that a time delay is required at all. I’ve seen a few of them blow where it looks like all the floors are detonated at the same time. I think those time-delay shots are mostly for the cool effect.

Perhaps for some buildings a time delay would be important. I gather that it’s more art than science, and that there are very few companies willing to tackle tall buildings.

I think it depends on wether you want the building to fall straight down or away from another building. In the second case time delay MUST be used. I think it has to be used anyway… the middlemost part of the building must blow before the outer in order that it collapses IN on itself (implosion) rather then just straight down and in a bigger pile.

What is the tallest building to be imploded? Is there an upper limit to this method, and, if so, how will really tall buildings, say, 100 stories, eventually be destroyed?

The mind reels.


“Believe those who seek the truth.
Doubt those who find it.” --Andre Gide

In this case “implosion” is a misnomer.

What really happens, is a series of cutting charges detatch key support members of a structure.

Picture four guys with machettes and four banana trees. There is a tree house strung between the banana trees. If all the guys swing at the same time, the tree house falls straight down. If the guys on the left swing first, the house falls left. By timing their swing, the guys can make the tree house fall any way they want.

I dunno about the sequences of the charges, but I do know it is an ‘art’! It is very precisely time charges (like prima-cord) that cuts through the structural pieces… then let gravity do the rest…if timed well, it should land in a heap, if not… it’ll take out the next door neighbor!! It is not for the amateur pyrotechic! I read the Anarchist Cookbook many times… and all I can make is muffins!!

I don’t believe in God, but I’m afraid of him…