Cob: Other Ideas on Jelly Roll Logs

[Darel Henman]

Robert,
  The straw or other natural material with strong fibers, strengthens
the soil/clay which will dry and crack otherwise.  Maybe in bags its not
necessary as it is in cob.  It can be mixed in the same time as the soil
is mixed and doesn't add much overhead.

RobertCCardwell at aol.com wrote:
> with straps.  The finished product would look like a roll of carpet.  Apply
> to the wall course seam down to seal the log.  Use earth crete morter  [clay
> and sand in ratio of 10 to 1 cement].  Lay the logs in a fashion similar to
> bricks and logs.
> 
I agree with Charlamain, you are in effect adding more time to the
construction process.  A properly done cob wall is a monolithic with
each layer strongly bond together.


The bab concept you mentioned more closely resembles the so called
"super adobe" method, more realistically called "bagged earth" method.

> Another variation of this could be to take the process one step further and
> compress the logs into planks.   Make a form of the appropriate size with
> two 12 foot 2" x 12" and 2" x 4" studs.

You might as well use compressed earth bricks (CEB).  Devices like the
man powered cinva ram can make these easily and quickly.  Larger powered
CEB machines can make more faster.  These bricks if applied raw will be
bonded together without additional mortar being required or if dried
alittle too much a mud mortar would suffice.

>   The studs would be used on the
> sides and ends of the jelly roll log and then nailed or bolted to the bottom
> 12 x 2.   The form made would be smaller than the jelly roll log.  The log
> would then be placed into the form, with the log being a little larger than
> the form.   The other 12 x 2 would then be placed on the top of the form,
> tamped down and fastened to the other 12 x 2.  Then drive your vehicle over
> the 12 x 2 and compress to form with the weight of the wheels.  Like driving
> on a ramp.  Take the plank out and apply to the structure.
> 
> A variation of this would be to use a little more physics and find a liquid
> when compressed gives off a lot of heat.   The heat generated would kind of
> be like firing an earth brick from the inside out.
> 

To ceramintize clay you'd need to reach at least 1500 degrees F or so. 
I wouldn't play with chemicals that could do this if there were any. 
Not to mention if there was such a chemical that its heating up under
compression would probably create an explosion, as the heated up
materials want to expand.


> Just some more ramblings......
> 
> bc

Darel