# Re: How to calculate capacity of two Log beams, one on top of the other ?

• To: <seaint(--nospam--at)seaint.org>
• Subject: Re: How to calculate capacity of two Log beams, one on top of the other ?
• From: THunt(--nospam--at)absconsulting.com
• Date: Thu, 19 May 2005 09:02:48 -0700

Helen,

If your beams are continuously in contact (or very close to it) the load to each beam will be proportional to their stiffness.  If the beams are identical, then they will share the load 50/50.

Thomas Hunt, S.E.
ABS Consulting

"Zhou, Helen" <HZhou(--nospam--at)stlouisco.com>

05/19/2005 08:41 AM

 To cc Subject How to calculate capacity of two Log beams, one on top of the other ?

When you have two beams with same sizes and simply supported, one on top
of the other with no connection between, I always think the bottom beam
shall be designed for almost 100% load, because load distribution is
unknown.

I am reviewing plans of the log home, have 23.5 ft span beam with 6000
lb concentrated load in the center and 240plf distributed load, M=51810
lb-ft. The engineer use two 14" dia Engelman Spruce, select structure
(fb=1100, Mu=24750 lb-ft, E=1,300,000), one beam sits on the other with
no any connection, the engineer calculation claimed total Mu=2x24750
lb-ft.

Thank you !

Helen Zhou
Saint Louis, MO

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