Analysis of Wide Flange beam with torsion force applied to the Web 1

[oengineer]

I am looking for an example of a wide flange beam that has a torsional force applied to it's web. Any suggestions/comments are appreciated.

 

[KootK]

If at all possible, I'd be delivering that torsion to the beam through one or more full height stiffeners. If you can manage that, then it become and ordinary torsion situation such as those covered in the AISC design guide on torsion.

 

[RaptorEIT]

oengineer: Like this?

 

[KootK]

Nice contribution Raptor. Where does that come from?

 

[RaptorEIT]

Koot: That is an excerpt from some training our chief engineer provided to us new civils within the company on how to attach hangers to an existing I-beam. We were taught to analyze the local effect using the appropriate ROARK case and then check global torsion like you mentioned.

 

[oengineer]

@ Everyone

I am sorry, I have a typo in the title of the post. It should read "Analysis of Wide Flange column/post with torsion force applied to the Web". The HSS tube is the beam framing into the column.

@Raptor77R
The equations you have provided should still be applicable to an HSS tube framing into the web of a wide flange column/post, correct?

 

[RaptorEIT]

@oengineer: The equations in my previous post are only for checking the local effects of web tear out under an eccentric load. You will need to evaluate the strength of the HSS tube, the connection weld, the local web tear out strength, and the column strength due to an eccentric load. Those would be a minimum without knowing exactly what you are evaluating.

Hope that helps.

 

[oengineer]

@Raptor77R

I have run a RAM element model to check the strength of the HSS tube beam & wide flange column. I will need to check the connection weld and the local web tear out strength.

 

[oengineer]

@Raptor77R

Does ROARK have a situation when the member coming into the web of the wide flange beam is a round tube (i.e. HSS 12.75x0.375)? Basically, the same situation you have in your picture except the TS4x4 is instead a HSS 12.75x0.375.

 

[RaptorEIT]

Oengineer: Not that I am aware of. It's the same loading condition, just different shape, so you would just use the radius of the HSS shape for the "b" term instead of half the depth.

 

[JoshPlumSE]

The AISC 15th edition manual has a yield line method that is similar to what raptor is showing. Plate Elements Subjected to Out-of-Plane Loads on pages 9-14 through 9-17. One of the cases is an out-of-plane moment (case c) that would fit with what you'd get with a rectangular member welded to the web of a wide flange.

It would be interesting to see how this method compares to Raptors....

 

[oengineer]

@JoshPlum

I will look into it.

@Everyone

Would any one know how to determine the thickness and dimensions for the stiffener or doubler plates needed for this situation in the Wide flange columns?