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internal wood structure to earth quake proof cob wall?

 
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hello everybody

i am in the process of building our cob home in oaxaca mexico. we live in heavily seismic zone, just this year, our region made headlines across the world for the heavy earth quake we had.

i am building a two story house, bottom floor cob, top floor wood. the second floor will be sustained mostly by posts and beams.

we are building the cob walls ontop of a rubble trench, reinforced cement slab and 1 foot above ground rock/cement stem wall. it will be 40cm wide.

here is my question:

would it make sense to plant smallish posts connecting the stemwall to the wooden ring beam ontop of the cob wall to make the house more seismically secure?

the idea behind this would be to help the cob wall move in the same way as the posts and the second floor in case of an earth quake. the counter argument, as i see it, would be that exactly the same logic could make the cob wall break open where these small posts are when the earthquake comes.

greeting, haux
 
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What little i have read suggests  using cob as infill only in seismically active regions.
 
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Yes, I think you would be much safer making posts that will completely support the second floor, then cobbing around or between them. A few diagonal brace posts (floor to ceiling) buried in the wall would probably be a good idea too.
 
hauxi haux
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Thank you for answers!

Yes, the 9 main posts will completely carry the weight of the second floor and roof. Through metal bars the posts will be ankered straight to the rebar in the foundation slab.

But thank you, so I think I will go with my idea of installing the vertical posts (I call them posts, even though they won't actually carry any weight) tying the ring beam to the foundation, hidden inside the cob wall.

I guess that would kind of make it a hybrid of cob and waddle and dob.
 
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