Built-up Beam ply-ply connection 1

[jonathanwilkins]

I've got an LVL (3-ply) supporting a large concentrated load...12,000# hanging into the side. The hanger will be a simpson hanger so no issues with that. I need to figure out the best way to connect the plies together of the supporting beam. Don't think the typical connection is sufficient. I've read through Breyer's book and don't believe he addresses this, I've also checked the NDS and they're fairly vague as well. What I'm pretty sure I need to do is be able to transfer, in single shear, 2/3 of the 12,000#. (1st ply will carry 1/3, the rear 2 plies the remaining). I come up with a lot of bolts. What's the best way to orient these bolts to reduce group action factor. Thanks.

 

[dhengr]

Jon:
The hanger maybe by Simpson, but it’s probably not one of their off the shelf stds. Look at their Glulam hangers, top flange hung or top flange saddle hangers; GLS/HGLS/GLT/HGLT, or something along that line. I would still want some bolts through all the members. The top flange saddle distributes part of the load to the 3-LVL’s, but some bolts through the LVL’s distributes some and ties the three together. Otherwise, your 1/3,1/3,1/3 is about right; but you have to transmit 1/3 to the first LVL and 2/3 through the first, some distance, etc. They should be able to size the top flange saddle to fit your 3-LVL’s in width, and the side plate or pates to fit their depth.

 

[seimike]

You might try screws i.e. simpson 1/4 SDS. They don't get adjusted with the group action factor. AT 4000# per ply that works out to about 17 screws per ply. They can be installed from both sides with location offset.

 

[jonathanwilkins]

Thanks for the responses. There is no available top flange hanger per simpson. We have to use a face mount.

Will probably use simpson screws for the connection. Hadn't thought of that.