Bending stress of plywood gusset plates

[idecharlotte]

I've always had difficulty finding the allowable bending stress of plywood and OSB in an application where it is to be used as a gusset plate. I can find stresses for its normal floor application, but I wouldn't assume them to be the same for orientation in a built up beam situation. I've checked with APA engineers and their website and can't find anything. Anyone else know where to look?

http://www.idecharlotte.com

 

[dhengr]

Ide:
Plywd. bending which has the bending normal stresses parallel to the grain of the outer plies is highest and best orientation, this is your floor diaphragm in bending. When the bending normal stresses are perpendicular to the grain of the outer plies, you have cross grain tension, not a good condition; but they are parallel to the grain of the next ply in, but this ply is at a less favorable distance from the N.A. of the plywd. sht. The plywd. in a built-up beam is strictly as spacer, it is standing on edge, and the grain parallel to the normal bending stresses is very small (about zero); the grain perpendicular to the normal bending stresses is again useless.

 

[RFreund]

I would look in here.

EIT

 

[charliealphabravo]

I have had the same difficulty identifying the actual shear values of plywood-only like for use in truss gusset plates. Most shear values are given for complete constructions. I think the reason may be that the actual effective capacity is closely related to the number/type/spacing of fasteners and the type and location of framing supports.

I think you want the following documents from APA. I think they have the entire 3" literature binder for pretty cheap. It might even be available by PDF download.

APA Plywood Design Specification
APA Engineered Wood Construction Guide
APA Nailed Structural-Use Panel and Lumber Beams
APA Diaphragms and Shear Walls

 

[charliealphabravo]

I also second the reference from RFreund. This publication is in the standard APA binder.