Truss Purlin 2

[smb4050]

Does anyone have information, load tables or physical measurements and materials used, of pre-engineered metal building trusses shown in the attached photo? Reportedly the building was built in the early to mid 1970's, and I'm fairly sure it's a Butler building. A side question, is anyone else having problems getting pre-engineered building manufacturers to provide engineering information or support on their building? Thanks smb4050

 

[ToadJones]

Not sure on the truss, but have I ever had trouble getting info on a pre-engineered building....ahh, yea, every single time I have to work on one.

 

[ajh1]

This does appear to be one of Butler's truss purlins. If you can give me the span and probable design loading I should be able to give you the original purlin design calcs. There is sometimes a metal tag on the truss with a part number. Knowing that part number would help verify that I give you the right stuff.
If you want to discuss this off-line give me a call:
Al Harrold
816-968-5719

 

[saad73joss]

Hello,
I was just curious on the subject
I m sorry i can not help
But I m really interested in How we calculate and execute the connection of diagonals with members? very surprised!
Cheers,

 

[smb4050]

Thanks for the responses. The truss span is 24'-0 center line of girder truss to girder truss. The trusses are 20.5" deep with 5.623" wide hat-shaped, cold-rolled bottom & top chords. I specifically looked for and did not see metal tags on any of the trusses. Any idea if the trusses had been designed under SJI specs or AISI specs in effect at that time? Thanks again, smb4050

 

[ajh1]

The design would have been to the AISI Specifications of the time. These were basically designed in 1976. I am attaching the full design data for a 25' truss purlin. This one is rated for 50 psf LL with a 5' spacing on the purlins. I am also attaching a part drawing for a 24' floor joist we had at the time which is the same individual components as the 25' truss purlin so perhaps may have been substituted to get the 24' bay spacing you are seeing. The floor joist was rated at 110 psf on 30" joist centers.

 

[ajh1]

It appears I can't link two different files to the same posting. Here is the 25' design data.

 

[spats]

Wow! Seeing the calcs takes me way back. I was there at the time... I'm trying to think of who RPL is in the "Made By" box in the title block. I was part of the Landmark development team. The joints were all electric resistance welded in a jig, all at one time, with the exception of the end diagonals. In my humble opinion, a very cool product.

 

[hokie66]

As usual, ajh1 does his best to help with information about Butler products. If other "PEMB" manufacturers were as accommodating, perhaps that industry would be better received by engineers.