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RE: Engineered lumber bolt bearing

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Title: Engineered lumber bolt bearing

Thanks Buddy, Tom and all.


The question was only about engineered wood versus solid sawn.  It occurred to me that a manufactured product utilizing some form of adhesive in the matrix would change the normal values more significantly.  If you look at the increases in shear capacity, flexural, compression and so on, the resistance to crushing and splitting in perpendicular to grain loading would be similarly increased by at least some value.


Apparently, the shear and flexure increases must be based more on the consistent nature of a manufactured product with less ambiguity than solid sawn as opposed to any real increase in the matrix capacity.




From: Showalter, Buddy [mailto:Buddy_Showalter(--nospam--at)] On Behalf Of AWC Info
Sent: Wednesday, September 26, 2007 5:56 AM
To: 'seaint(--nospam--at)'
Subject: Engineered lumber bolt bearing


LVL and PSL use the same dowel bearing strength equations (values) from the NDS(r) as solid sawn lumber and glulam. The EWP manufacturer will list the appropriate specific gravity to use in their NER (as Tom pointed out). Typically they'll specify the same G as the material they use to manufacture the product. If there are any increases, that'll be in the NER.

The only additional clarification is that you would only use the perp to grain value if your LVL/PSL is loaded perp to grain. You would use the parallel to grain dowel bearing strength if loaded parallel to grain. Hankinson if somewhere in betweeen. I just wanted to make sure I covered that, because it wasn't clear to me if your question was only about engineered wood versus solid sawn or also parallel vs. perp.



John "Buddy" Showalter, P.E.
Director, Technical Media
AF&PA/American Wood Council
1111 19th Street, NW, Suite 800
Washington, DC 20036
P: 202-463-2769
F: 202-463-2791

The American Wood Council (AWC) is the wood products division of the American Forest & Paper Association (AF&PA). AWC develops internationally recognized standards for wood design and construction. Its efforts with building codes and standards, engineering and research, and technology transfer ensure proper application for engineered and traditional wood products.

The guidance provided herein is not a formal interpretation of any AF&PA standard.  Interpretations of AF&PA standards are only available through a formal process outlined in AF&PA's standards development procedures.



From: Paul Feather [mailto:PFeather(--nospam--at)]
Sent: Tuesday, September 25, 2007 17:42
To: seaint(--nospam--at)
Subject: Engineered lumber bolt bearing
Are LVL and PSL lumber considered perpendicular to grain for bolt bearing v=
alues? Seems like you would get a higher value for an engineered product i=
n an epoxy (?) matrix as opposed to natural wood grain.
Is there an increased capacity available?
Mr. Showalter, are you out there?
Paul Feather PE, SE