[Cob] foundation, concrete

[Predrag Cvetkovic]

Thanks again! I've tried to visit that URL, it seems the page doesn't exist
more, but I found other pages about professor Gernot Minke and his books.

I understand that nothing can help in a big earthquake, and I only would
like to prevent the house from smaller ones and from smaller earth slipping
(of course I should avoid choosing such places). In that case maybe grade
beam is not necessary?

I've already heard about "light clay" but your explanations were really very
helpful.
Regarding wattle and daub I must admit that I haven't got a sense how earth
and straw will stick to wattle (and plaster as well) and what will happen
years after that? It seems to me cob will better accept plastering then
wattle and daub or I am wrong?
My dilemma is also whether to use vertical bearer beams if I use cob or
light clay? As I can see through web, people don't use these. Or I would not
break cob structure and would add vertical beams only partially caught with
cob?

The idea about using roof to give potable water is also very interesting. I
was informed only about obtaining non potable water.

thanks for your patience and help
predrag


Amanda wrote:

> If this is still available take a look at this--it didn't turn up when I
> just tried to find it--a short booklet on design of earthen buildings for
> seismic areas by Gernot Minke and his students--and the price is right.
I
> emailed them to ask.
>
> http://www2.gtz.de/Basin/publications/books/ManualMinke.pdf
>
> I really don't know enough about the subject to speculate on a grade
> beam--with or without reinforcing bar.  Not much is going to help in a big
> earthquake.  Various methods will do more or less good for the smaller
ones.
>   Since the big fault is quite a ways away from me, we tend not to think
> about it in design situations.
>
> There is a technique called "light clay"  in which straw--not chaff--is
> tossed with clay slip to form walls of nearly any width you want--packed
> firmly into forms that are then moved up.  More straw, less (none!) sand
> than cob.  Horizontal reinforcing bar--almost any kind--bamboo is good,
weed
> tree saplings--sound like a use for them, metal--put in before you move
the
> forms.  once the wall is up, then it gets to dry for a while.  And then it
> gets plastered, usually.   You might or might not want to use it for
> external walls, or if you want the lovely wavy cob walls of the cob
revival.
>    But internal walls--at the same kind of thickness as the wattle and
daub
> might be wonderful.