×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Welded studs to transfer lateral load
2

Welded studs to transfer lateral load

Welded studs to transfer lateral load

(OP)
I have a situation where I have a concrete diaphragm/slab  sitting on a steel beam, and I want to transfer some horizontal force into this beam using welded [shear] studs. The beam is sized to where it will be just fine without any composite action, BUT the number of studs I'm coming out with (for the transfer) are very small. So I am just wondering should I use some sort of minimum number of studs so that the studs are not damaged from some sort of [attempted, partial] composite action? One reference I read said to use (as a minimum) 25% of the number of required studs for full composite action. But I can find nothing in the code (officially) for this. Thoughts?

 

RE: Welded studs to transfer lateral load

This is some quite interesting problem the solution of which I think resides in study at the limit state. If one comes to the simplifying thought of that for a steel beam competent without any need of composite action to support the vertical loads the slab is thought to rest on the bean (accompany it in its downwards deformation) one would be able to dismiss any thought of tensile action on the stud (as an applied load at the interface) and the problem becomes simplified to add two shears, the one coming from the tributary shear at the interface for the stud in the actual composite action allowed by the competent beam without need of such, and your purposedly transmitted shear; vectorial sum of both to be competently taken by the studs at the given separation. So I think you can calculate the thing well this way.

RE: Welded studs to transfer lateral load

I would use a 25% minimum (as slickdeals reference suggests)  to avoid damaging the studs due to the composite action that will result from gravity loads (the beam doesn't know you don't want it to act compositely under gravity load).  You will not find this limit explicitly in the codes, but p16.1-311 (the Commentary to I3) of AISC 2005, item 3, recommends this limit.  

RE: Welded studs to transfer lateral load

You might do a search here on Eng-Tips - there was a thread on this topic at one time that discussed all the issues involved - especially the concern that the flexural composite action on the studs and the lateral drag had to be combined properly - the studs on one half of the span getting higher stress than the other half due to the direction of the lateral drag of teh diaphragm into the beam.  

 

RE: Welded studs to transfer lateral load

I generally set the minimum number of studs at 12" on center for the full length of the beam and see where that puts me.  Usually, it's more than enough, but simple for the contractor to place.

Mike McCann
MMC Engineering

RE: Welded studs to transfer lateral load

I vote for Mike's solution.   

BA

RE: Welded studs to transfer lateral load

(OP)
Thanks for the feedback everyone. cheers

RE: Welded studs to transfer lateral load

The check of the stud may be a bit more complicated than just by the formula considered. As in the comics, Methinks 6" is too little depth for a 3/4" connector. Go for the code.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources