Jordan,
This doesn't exactly answer your question, but at a seminar I attended on segmental retaining walls the presenter said that you had to design the walls as one wall unless the horizontal distance between them was at least twice the height of the lower wall. He didn't give us the theory behind the rule-of-thumb, though. Also, he said that you needed to check the global stability of the whole tiered system. He said that he had seen at least one case where a whole hillside gave way behind the walls rather than the walls themselves giving way.
Wesley C. Werner
-----Original Message-----
From: Jordan Denio [mailto:jordan@AshleyVance.com]
Sent: Thursday, September 13, 2007 5:28 PM
To: seaint@seaint.org
Subject: RE: Retaining Wall Questions
From: Jordan Denio [mailto:jordan@AshleyVance.com]
Sent: Thursday, September 13, 2007 5:28 PM
To: seaint@seaint.org
Subject: RE: Retaining Wall Questions
I don’t have the answer for that as I’m looking for opinions/advice to determine what the size and configuration of the walls should be. If it helps the discussion, let’s say the wall upper wall is set back 5’ from the lower wall and all the sliding is resisted by a key. The lower wall retains ~8’-0” and the upper wall retains ~4’-0”.
From: Jnapd@aol.com [mailto:Jnapd@aol.com]
Sent: Thursday, September 13, 2007 9:10 AM
To: seaint@seaint.org
Subject: Re: Retaining Wall Questions
How far apart are the walls...vertically and Horizontally
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