[Cob] Materials for Strengthening Clay Based Soils

[Frank Hanlan]

Hi All,

The following article is from www.gizmag.com and is about strengthening bricks but it might be worth testing with cob.


Wool and seaweed makes bricks stronger
By Ben Coxworth 21:04 October 5, 2010 

http://www.gizmag.com/bricks-made-with-wool-and-seaweed/16580/?utm_source=Gizmag+Subscribers&utm_campaign=8d30216ab8-UA-2235360-4&utm_medium=email
 

In a collaborative study on sustainable
building materials, researchers from Spain’s University of Seville
and Glasgow’s University of Strathclyde have created bricks that
contain sheep’s wool and a polymer derived from seaweed. Clay-based
soils were provided by Scottish brick manufacturers, while the wool
came from Scotland's textile industry, which produces more of the
stuff than it can use. The polymer was an alginate, which occurs
naturally in the cell walls of seaweed. Mixed together, the three
substances resulted in bricks that were reportedly 37 percent
stronger than regular unfired bricks. “These fibers improve the
strength of compressed bricks, reduce the formation of fissures and
deformities as a result of contraction, reduce drying time and
increase the bricks' resistance to flexion,” the study’s authors
concluded.



The bricks are environmentally-friendly
in that they are composed of sustainable, non-toxic,
locally-available materials, and don’t require the expenditure of
energy that goes into the firing of other types of bricks – it
wasn’t mentioned, incidentally, how their strength compared to that
of fired bricks.



The wool-and-seaweed bricks also don’t
create the carbon dioxide that is generated by the production of
Portland cement, which is an ingredient in most types of concrete.
There is no word yet from Seville or Strathclyde on whether or not
there are plans to produce the bricks commercially.
The research was recently published in
the journal Construction and Building Materials.

Sincerely yours,
Frank Hanlan

Edmonton, AB

If you have not demonstrated that you can hear the truth and still act then don't expect to be told the truth.  

If we have not ensured that global green house gas emissions have peaked and started down by the end of
2015 then it will be next to impossible to keep global average temperature rise under 2.4C which will mean
widespread flooding and the displacement of 400 to 500 million people.