Moment plywood gusset plate

[JSanchez88]

Hi,

I've been asked to check a framing connection in a residential house. The connection consists of two 2x6's and they're connected with a 3/8" plywood gusset plate. Connecting the gusset to the 2x are 8 staples on each side of each 2x6 (32 total). Is there a certain procedure I should use to go about checking to ensure the gusset is adequate for the given condition? Any advice or suggestions is greatly appreciated.

Thanks.

 

[woodman88]

Determine the plywood and staple allowable values. Calculate the forces in the member for a moment and/or hinge connection. Check that the plywood and the staples allowable values work for the forces. I would use a personal safety factor for this condition of 0.7 the allowable values.

Garth Dreger PE - AZ Phoenix area
As EOR's we should take the responsibility to design our structures to support the components we allow in our design per that industry standards.

 

[JSanchez88]

Thanks woodman88. I appreciate your advice.

 

[MiketheEngineer]

Most people in the industry consider it a pin connection. Find your forces and do as Woodman says.

 

[hokie66]

Properly designed plywood gusseted moment connections do not have right angled corners. And the "carpenter" has already made the connection useless for carrying bending moment by sawing through the corners, in both directions. If these are supposed to be rigid frames, I wouldn't rely on them.

 

[dhengr]

I don’t like the sharp reentrant corner cut in the plywood knee, and the orientation of the grain in the outer plys stinks too. This is a mansard or gambrel roof frame, I bet. If you (they) had it to do all over again, I would make those gussets more triangular in shape and orienting the grain in the face plys parallel to the long bottom leg of the triangle. I would use thicker plywd. to bring more plys into play with tension parallel to the grain. The existing gusset won’t check worth a darn because you only have the middle ply acting in tension parallel to the grain. And, this is true wether the framing causes the tensile stress to be on the inside or the outer corner. Otherwise, I agree with Woodman88. If all else fails, you could reduce the moment at that knee with a collar tie.