[Cob] off the concrete subject

[Damon Howell]

Ocean was right in saying it was a silly question about straw in  
concrete. I didn't think of it causing such a stir either, but we may  
talk about what we feel needs attention, and anything to do with  
concrete gets cobbers going every time. But unfortunately, cob has  
it's place, and on the ground isn't it. I have done quite a bit of  
reading on Roman concrete, which is made from lime and volcanic ash,  
mixed extremely dry, then packed into forms. The process was pretty  
much like rammed-earth and it's still there 2,000 years later. Cob  
doesn't really lend it's self to compaction. Just like in concrete,  
cob is stronger the drier the mix. But I've noticed when I mix dry I  
feel like the clay doesn't bond and will not form a solid structure.  
If I pack it, it bonds, it just doesn't seem to stay together as  
well. Can anyone enlighten me on this?

Damon