[Cob] foundations for sandy soil

[livin_and_learnin at yahoo.com]

You might do some research on the type foundations that are used in marshy ground.  They are wider than for rock bases, and they float, so to speak, not needing a hard base.  Also, pier foundations with attached rubble and 8-inch deep, concrete bond beam.  I haunted the library when I was designing my cob home many years ago.  I have forgotten most of it after I decided what our site needed.  I also agree with Damon in USA  about finding out what others in your area use.  What works, works; and what doesn't will surely show, if it's been around long enough.
 
B.M. in Oklahoma
 
 
 
Message: 1
Date: Tue, 8 Dec 2009 22:50:01 -0200
From: guilherme bortoli <guigrena at hotmail.com>
Subject: [Cob] foundations on unstable sandy soil
To: <coblist at deatech.com>
Message-ID: <COL112-W21D9D8D9DCC7F685F238E6CB8E0 at phx.gbl>
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Hello!

I?m in Brazil, in Florianopolis, and I?m planning 
to build a small house myself with cob!

I?m with a doubt about the foundations, and I found 
you as a cob builder, hopefully you guys can help me.

I?m ins a very sandy soil, going 1,5 meters down in 
the soil I still not found a hard soil.  I cannot find a good choice to build 
the foundations...... should I do it with reinforced concrete (how deep should 
it be and how wide)? or can I just buid a steam wall with stones, wider on the 
bottom?

(if I do it with concrete, seems as will be harder 
to build round walls, because the foundations should be square)
thanks for your help

Guilherme