Cob: Re: earth floors

[Darel Henman]

Matthew,

"Matthew HALL(SED)" wrote:
> Where have you 'read' this about the fermentation of natural fibres in clay matrices? Do you have a
> reference for this work i am very interested in finding out more about the use of natural fibres in
> soil. 
It's common knowledge among the masonary people here and the strongest
lime-mud and most resistant to water is the kind made with the fermented
rice straw. 

Its in a book entitled:   " ¶Š¯m’´ŽÀ—pnƒeƒNƒjƒbƒN“Ç–{ "      can'T
read that
which in English is something like "Masonary [Real Application]
Technique Reading Book"
Published Septemeber 2001.   The publisher's URS is
http://www.xknowledge.co.jp/
but its in Japanese.  So I doubt that it'll help you.

>Does the use of lime enhance the fibres adhesion within the soil: the mechanisms of lime
> stabilisation are quite different from cementicious bonding using OPC or similar.
> 
Yes this is reported to be this case.  Especially, since even after
fermenting the straw cutting seperately they mix it in the lime-mud and
let it sit for one to three months.  For important structures the let
the mixture age longer. 

This web page has very elementary introduction to plain lime-mud
	http://www.shikkui.com/function.htm

It doesn't describe the "Dosa-Shikkui" which is made in Kochi and uses
the long term fermented straw cuttings and is the strongest lime-mud
that can be used on the exterior as well.

I can't find anything in English for Kochi's "Dosa Shikkui".

By the way dosa-shikkui is also used to make sculpures on the building.

Find a Japanese friend at your school to translate this for you.

This japanese page talks about the fermentation as well as the lime
making:
    http://www.geocities.co.jp/SweetHome-Green/4660/500.html

The following is about the best I can find for you.
These have pictures, if you cant find the <continue> prompt here are the
seperate urls for the series of pictures.

They burn the limestone is a large vessle that is earth bermed.  The
limestone is burned with coke and industrial salt is added (for some
reason).
(burning the limestone (picture 4 shows that salt being added.)
1st page:  http://www.ehdo.go.jp/kagawa/college/nakawaki/seihou.html 

(taking the oxyized limestone out)
2nd page:  http://www.ehdo.go.jp/kagawa/college/nakawaki/seihou2.html

(straw being selected, smash rolled, then  cut to size)
(this page mentions that the straw is fermented 2 to 3 months.
3rd page:  http://www.ehdo.go.jp/kagawa/college/nakawaki/seihou3.html

water is added when needed.  people can tromp about and mix it more as
well during the fermentation process.

(straw through in barn, water added, tarp thrown over to keep natural
bacteria warm)
picture 16 here is the lime and dry earth mixed mountain.
4th page:  http://www.ehdo.go.jp/kagawa/college/nakawaki/seihou4.html

(mixing the lime-soil, with the fermented straws.
picture 20 here shows the two old day mixture going to the mixer once
more.
5th page:  http://www.ehdo.go.jp/kagawa/college/nakawaki/seihou5.html

Re: using sado-shikkui
1st page: http://www.ehdo.go.jp/kagawa/college/nakawaki/kabegihou.html
2nd page:  http://www.ehdo.go.jp/kagawa/college/nakawaki/kabegihou2.html
3rd page: http://www.ehdo.go.jp/kagawa/college/nakawaki/kabegihou3.html
4th page: http://www.ehdo.go.jp/kagawa/college/nakawaki/kabegihou4.html
5th page: http://www.ehdo.go.jp/kagawa/college/nakawaki/kabegihou5.html


Darel