Truss / Joist Hanger Lateral Loads

[BSVBD]

I am currently researching ESR reports for potential lateral load capabilities in truss / joist hangers.

I have a common situation where the common trusses are bearing into the side of a truss girder. This truss girder, while it interrupts my shear wall, "could" serve as a shear strut between two full height wall sections / segments.

I need to transfer lateral loads. Although the Simpson load tables do not offer lateral load values for truss and joist hangers (i.e. LUS28) i cannot believe that trusses aren't capable of providing "some" lateral design value.

I've contacted Simpson twice, unable to speak directly with engineering thus far. The last contact directed me to applicable ESR reports that i am currently researching.

Any thoughts?

Thank you!

 

[KootK]

Any thoughts?

Does the diaphragm shear being transferred not reside in the roof sheathing, making transfer to the girder relatively simple via nailing etc? Perhaps I'm misunderstanding the situation.

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.

 

[msquared48]

If the Girder Trusses are top hung, are you looking at not having to block between the trusses and the bearing surface of the top chord, taking any lateral through the Girder Truss connector?



Mike McCann, PE, SE (WA)

 

[BSVBD]

Koot... Yes... the shear will transfer through the roof diaphragm. It will then be transferred through collectors... hurricane ties. Unfortunately, a girder interrupts the shear wall, and thus, the hurricane ties. Thus, the inquiry regarding truss hangers.

Koot... are you suggesting using nailing in addition to the hangers - perhaps, since the hangers may not have been designed to interactively support gravity and lateral loads? I've done similar things before. I'll consider it. Or please explain if i am misunderstanding...

msquared... the Girder Truss is a common triangle that will bear on top of the continuous top plates.

msquared... there is nothing between the trusses and the bearing surface. The trusses bear on top of the bearing surface which is the continuous wood top plates. Our typical practice is to have the Simpson H1 hurricane ties serve as the collector to transfer the diaphragm shear to the shear wall.

msquared... thank you for the suggestion, but, blocking is not an option since we've always been able to find an alternate safe route of transfer.

My initial inquiry... has anyone had any experience, success, other... in applying a lateral load through Simpson hangers?

Thank you both for your suggestions.

Any others?

Thank you!

 

[KootK]

A sketch of your situation and the particular shear forces that you`re hoping to transfer would be a great help (to me at least). As you know, some hardware products can transfer lateral loads in addition to gravity loads. That said, my strong suspicion here is that your sheathing will take your shear straight to the girder top chords and lateral load resisting hardware will not be required at the supported truss ends.

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.