Frame in Staad pro

[hello12345hello]

Hello
I am trying to analyse one story frame in Staad pro. see attached frame image for reference. the frame is about 30ft high and i am adding HSS girt at some intermediate location for wind load. How that HSS girt is going to be connected with column. do i have release the moment for HSS beam ?
Thank you

 

[Enhineyero]

You have to release the end moments of the girts, I think it is difficult to make a moment connection for such members.

It is always advantageous to design girts as a simple beam due to ease in installation of girts on site. Also I think that loads on the girts and not that high (usually it is governed by serviciblity)

 

[JedClampett]

Yes. You need to release the end moments.
But I would leave them out and just analyze them separately (by hand). They might affect the behavior of your model, taking axial loads or making the frame stiffer.
All of these might reflect the actual behavior, but are not the traditional assumptions used in building analysis.
And why are you using HSS's for girts? How about channels and sag rods?

 

[ToadJones]

I agree with everything already said....except you probably need siding girts spaced closer than 15' unless you have some stiff cladding.
HSS for girts seems odd.
Are you trying to serve some duel purpose with the HSS girt?

 

[hello12345hello]

it's Unbraced beam so thought HSS is better than channel for wind load. i will release the moment for HSS beam and consider it's just pin pin connection for analysis purpose. But due to HSS girts present at intermediate location my wind load application on frame still remains same at node 3 5 7 and 4 6 8 based on tributary height. And at node 7 8 15 16 i have moment connection under gravity and lateral loads. but do i have release any moments for column ?

Thanks

 

[hello12345hello]

and also exterior glazing is attached to HSS.

 

[Enhineyero]

the problem with HSS is that you have difficulty on site doing the connection (i usually use Lipped channel) it is difficult to bolt an HSS girt to a column because you have to make your bolt go thru your HSS and thru your columns, also just use a hand calculation for the girts. just apply an additional load to your columns (due to the weight of the girts) in your STAAD model.

 

[hello12345hello]

So , it's just pin pin connection for analysis purpose. But due to HSS girts present at intermediate location my wind load application on frame still remains same at node 3 5 7 and 4 6 8 based on tributary height. And at node 7 8 15 16 i have moment connection under gravity and lateral loads. but do i have release any moments for column ?

Somebody please clarify my doubt to analyse frame in staad pro. ?

Thanks

 

[Enhineyero]

You don't have to release any moment in you column