[Greenbuilding] concrete vs block vs ___foundation wall

[Chris Green]

Rob Tom wrote:
> deconstructiing a rebarred/core-grouted CMU wall would likely mean a 
> mess of debris that you'd have a hard time even hauling to a landfill 
> without first going at it with either dynamite or diamond saws.
This reminded me to mention the existence of "non-explosive or silent 
demolition agents." These non-toxic aluminum-silicon-mineral compounds, 
invented by the Chinese centuries ago, is something like an expanding 
mortar mix.
Take the powder, mix water into it, and pour it into holes drilled every 
so far in concrete or rock(s) and wait  a varying amount of time 
(depending on which brand and formula you're using ) until the mix 
expands and cracks whatever needs cracking.
The expanding mix exerts a force of about 18,000 PSI. A lot more than 
the dry wooden pegs used to crack the blocks the pyramids were built with.

It's good to know this product exists if you're faced with removing rock 
or concrete near anything that could be damaged by blasting. Or near 
anyone who would be upset/ disturbed by blasting.

And it's likely to be a lot cheaper, since a supply of this agent will 
cost about $150US from at least one supplier, plus shipping. No blasting 
tickets are needed. The money saved could be spent on the honkin' big 
hammer drill you'll need, if you don't already have one.

This seems to be highly cost effective for smaller jobs, but I wouldn't 
try cutting out a 2200 sq ft. basement 9' deep with this stuff.

Some brands I've found:

Dexpan from  http://www.archerusa.com/Product_Dexpan_En1.html
Bustar from   http://demolitiontechnologies.com/ (Bustar is the 
successor to the Bristar product they formerly sold.)
Fract AG. from:  http://www.daighcompany.com/
Bentonamit from: http://www.betonamit.net/
--Canadian distributer of Bentonamit: 
http://www.trowelex.shawbiz.ca/betonamit%20and%20boulder%20buster.htm
S-mite from:  http://www.soc.co.jp/sumitomo_e/business/const/s-mite.html
Spanish Language site for the manufacturer of Bustar:
http://www.kayati.com/portada.html

Wiki article about these agents.
http://en.wikipedia.org/wiki/Non-explosive_demolition_agents

In all cases, read the instructions.(that sheet of paper you read after 
something's gone wrong...)
Good eye protection is strongly advised. As well as protection for the 
not-so-good eye...

Cheers,

Chris Green.