Nail end edge/end distance for end of beam connection
Nail end edge/end distance for end of beam connection
(OP)
I have an existing 5 1/8" wide roof glue-laminated beam. I need to connect a 2x8 joist to the end of the glue-laminated beam (cantilever end of the beam). I am using the joist hanger from the Simpson (MUS28). My concern is that the nails are very close to the edge of the glue-laminated beam (end section of the beam as shown in the attached sketch). The NDS has requirements regarding the end/edge distance for the bolts. Is there any requirements for the end/edge distance of nails connected to the end of a beam of this nature? Any other detail I can use to resolve this issue?https://res.cloudinary.com/engineering-com/image/upload/v1453073810/tips/CCF01172016_dmgyrz.pdf





RE: Nail end edge/end distance for end of beam connection
Regardless, it seems to me that the real concern would be END GRAIN WITHDRAWAL. If there is any reliance on withdrawal involved in the connection, it is not allowed by NDS for nails in end grain.
Lateral load values for nails in end grain should be about 2/3 of the values for side grain parallel to the grain.
RE: Nail end edge/end distance for end of beam connection
If these hangers are placed with any flanges turned in and placed at the end of the beam, they should still be ok. Done all the time.
Mike McCann, PE, SE (WA)
RE: Nail end edge/end distance for end of beam connection
Also, what is meant by "at the encouragement of the beam" ? I'm not familiar with that term.
RE: Nail end edge/end distance for end of beam connection
Mike McCann, PE, SE (WA)
RE: Nail end edge/end distance for end of beam connection
RE: Nail end edge/end distance for end of beam connection
Or make a custom steel hanger that wraps around glulam beam and again screw it from side.
Structural timber engineering
RE: Nail end edge/end distance for end of beam connection
Since the new beam is a single 2x8, I would surmise that the load is relatively light.
End nails do have design values so that still seems viable.
With a side lapped connector, it seems to me that there would be a need for a much larger connector. A standard metal hanger with concealed flanges is readily available for the single ridge board so it is a matter of checking the capacity with the design load.
RE: Nail end edge/end distance for end of beam connection
If there are end grain cracks in the glulam, then shear design value per nail is just theory. In reality you'll just have a 'weak' link.
Structural timber engineering
RE: Nail end edge/end distance for end of beam connection
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Nail end edge/end distance for end of beam connection
I am also of the opinion that manufacturers of glue laminated beams (or their related association) have engineering details about nail and screw connections into the ends of such beams, after all there is abundant data for such connections on regular wood .