×
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

Yield Line Analysis for Web Connection In Direct Tension

Yield Line Analysis for Web Connection In Direct Tension

Yield Line Analysis for Web Connection In Direct Tension

(OP)
Hi to all,
I have stumbled upon an article on AISC by Richard H. Kapp (Engineering Journal 2nd Quarter 1974). My question is related to the applications of the yield line analysis for local bending in column webs. In what situations does one consider the column flanges to be fixed/pinned? In other derivations that I have seen (for example one by Mr. Muir, http://larrymuir.com/Tech.aspx) the engineer considers the flanges to be pinned. Can someone clarify?

RE: Yield Line Analysis for Web Connection In Direct Tension

Like many analyses in our Profession, the consideration of whether to apply pin-pin or fixed edge restraints to this application of Johanssen comes down to engineering judgement.  I've heard arguments that the web should be treated fixed-fixed due to the welds to the flanges (but what about flange rotation in this case?), as well as arguments about applying a more conservative pin-pinned approach (but then what about a well latterally braced situation?

My honest opinion:  If your forces do not cause much rotation of your "support" when applied at a reasonable eccentricity (say 1/4 flange width), then consider your supports to be reasonably fix-fixed.  Otherwise go pin-pin.

Note:  I've seen a break-down by Class of sections (ie: Class 1 pin-pin, Class 3 fix-fix, Class 2 by judgement with a rotation suggestion), but I don't buy it... This really ALWAYS needs to be considered as part of how STABLE and STIFF your supports should be.

Hope that helps,
Cheers,

YS

B.Eng (Carleton), P.Eng (Ontario), MIPENZ (Structural-New Zealand)
Working in Canada, and missing my adoptive New Zealand family... at least I brought the little Kiwi with me!

RE: Yield Line Analysis for Web Connection In Direct Tension

My practice has always been to assume fixed edges for HSS members and pinned edges for wide flange shapes. This is because the flanges of a wide flange can rotate, as has been pointed out.

I think you may find others in the literature who also suppoort this practice.   

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