Concrete slabs can last for millennia, but most commercial buildings in America are disposable. Thus there are thousands of abandoned concrete patches blighting the landscape. These are difficult and expensive to remove.

Achilles’ concrete is a disposable slab. Before it is poured, fiberglass reinforcing rods are laid in a grid pattern. Each rod is hollow and is filled with plastic explosive. Years later, after the site has been abandoned, a blasting cap is placed on an exposed section of rod, and, upon detonation, the entire slab is instantly cracked up into small blocks that can easily be hauled off.

The plastic explosive is only sufficient to crack the slab, and doesn’t loft debris in the air.

Achilles’ concrete may also be used in short sections of road or airstrip, to instantly disable them in the case of invasion. A popular option with small countries.
-- pluterday, May 04 2003

At first glance this seems like an eminently sensible idea. But, I have to ask, just because your explosive seams have broken the surface and made it unfit for most purposes, what device has caused the disposal?

If you are not going to truck the debris away, I would prefer that you left the concrete slab intact until I have decided whether it can be adapted for another purpose.
-- jurist, May 04 2003


Terrorists will rejoice... no need to carry heavy c4 around, a pocket full of blasting caps will enable them to take down buildings.

Don't forget to renew your Al-Qaeda membership.
-- MikeOliver, May 04 2003


If the rods were placed in a circular pattern, the concrete slab could be transformed into "rollslabs" for efficient removal.
-- FarmerJohn, May 04 2003


...or in a spider-web pattern. You could then elevate the resultant columns to form a concrete Stonehenge on the site.
-- pluterday, May 04 2003


// take down buildings //

I would hardly think so. [pluter] has only provided for cracking the slab, not the footings. If the weight of the building is low enough that it is entirely on the slab, it's not very likely a terrorist target.
-- lurch, May 04 2003


How 'quake-proof is this combination of design and material?
-- thumbwax, May 04 2003


If you had a shake detector wired up you could blow the building up just before the quake destroyed it. Sort of a neener-neener-neener moment delivery system.
-- bristolz, May 04 2003


I don't think cracking the foundations of any building would be well recieved. What about the shock wave from the blast? Also, if the slab was accidently cracked (or deliberately) would the building have to be removed to replace the floor?

How stable is this explosive anyway? Would a lightning bolt or a carelessly discarded cigarette set it off?

No?

Are you sure?
-- MikeOliver, May 05 2003


[MileOliver] Don’t worry so much, the crack engineers here at Boondoggle Industries will take care of your concerns.

All we need is your address…

I think that you are underestimating the ability of the public to become inured to almost anything, no matter how potentially lethal. Don’t fighter pilots have explosive bolts as part of their ejection seats? Don’t you drive around every day with an air bag concealed just inches in front of your nose. And isn’t the inflator behind that bag just a modified explosive?

Americans trust technology. And they trust Boondoggle Industries.

Don’t worry about shock waves and cigarettes and such things. Buried in the slab of your local Wal-Mart, the “explosive” that we use is impervious to smokers. And the explosive is really more of an inflator anyway, more like the stuff behind your airbag, so there is not much of a shock wave. The purpose is to simultaneously destroy the slab reinforcement and to generate enough internal gas pressure so that the slab cracks. But the pieces don’t fly up into the air or anything.

You’ll hardly even notice it.
-- pluterday, May 05 2003


Famous last words.
If all of the rebar in the slab remained intact and you placed the explosive in a geodesic pattern, then by lifting in the centre you could create lovely concrete domes of the future.

Run Logan.
-- 2 fries shy of a happy meal, May 05 2003


I croissant this, but only because you'd hafta drill into the concrete to get to it. Good.
-- galukalock, May 05 2003


Hey, I'm all for large exploding things, as long as I'm not living in it.
-- wittywastrel, May 05 2003


[Mike] - My point is not to say it wouldn't cause a lot of damage. I'm just thinking that if someone blew the superflat slab over at the WalMart warehouse, the cops would be looking for disgruntled employees before they thought about Osama.

[bris] - that was a laugh I've desperately needed this week.
-- lurch, May 05 2003


I'm a bridge technician for a well known, multi-national engineering company. If bridges were built of such materials, we would not hesitate in recommending the demolition of a structure, as this can quite often outweight the cost of building a new bridge.
-- junglemassif, Jul 15 2003


Plus this would be quite exciting. The cost of picking up debris could be offset by selling tickets to a bridge explosion event. Can fireworks be embedded as well?
-- Worldgineer, Jul 15 2003


Just put in a network of PIPES. They can be filled after the fact with liquid explosive. The pipes would best be filled with a low hazard liquid while the building was in use, to prevent anyone from casually pouring in liquid explosive unauthorized. After a drain, pump-out or or compresses air purge, the explosive could be put in just for demolition.
-- TD3, Oct 29 2004



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