×
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

Design of Column Shear Lugs.

Design of Column Shear Lugs.

Design of Column Shear Lugs.

(OP)
I'm looking at the use of stub W section 'lugs' welded to the baseplate of larger W shapes to improve the transfer of high lateral loads (100 kips approx).  This is in conjunction with high uplift forces on the column (80' tall building with little dead load).  Uplift also in the magnitude of 100 kips. Also info on the design of 'grout pockets' to accept the lug.

Can anyone provide a source for literature, papers, pdf file, etc. (LRFD preferred, but ASD info OK, too).

Dik

RE: Design of Column Shear Lugs.

AISC Design Guide #1 talks about the design of shear lugs.

neffers

RE: Design of Column Shear Lugs.

I'd say Design Guide 1 also but I do not think that using "W' stubs is covered.
Sounds like a good idea though.
The design of conventional plate shear lugs is covered in DG1 and is rather straight forward. I'm sure the concepts could be adapted for your application.
Watch out for DG1, second edition. There are more errors in it than in the movie Major League.  

RE: Design of Column Shear Lugs.

dik-

Are these columns going into piers, grade beams, ftgs, caissons?  Is this a braced frame bulding?

I have a pretty slick detail that goes along with a schedule (for braced frames), but it won't work on isolated piers.  If you have some length of concrete (like grade beams), it works very nicely.  It's probably less expensive than blocking out for, and providing, shear lugs.  
 

RE: Design of Column Shear Lugs.

EIT-
Let us in on it!!

RE: Design of Column Shear Lugs.

(OP)
It is a braced frame, going into piers cast into a foundation wall/gradebeam.  It is a matter of confining the grout pocket with ties and vertical reinforcing.

Dik

RE: Design of Column Shear Lugs.

I'll send it to your email.

RE: Design of Column Shear Lugs.

dik-
Check your email.  I attached the detail I was talking about and another that goes with it (especially if you have high uplift forces like this).

RE: Design of Column Shear Lugs.

I prefer to use a cast in plate with headed studs to transfer the shear. The anchor bolts go thru this plate and are the hold down fastening for the column base plate 2" above. Base plate is still grouted. Side plates are then field welded between base plate and cast in plate to transfer shear.

Easy to install.

No messing around with shear lugs which are not very often installed correctly!

RE: Design of Column Shear Lugs.

jike-

My detail is similar, but I use rebar welded to the embed plate because it's often hard to get headed studs to work with a long, relatively thin member (such as a grade beam) with App. D.  I have an embed that take the shear through shear friction, and the column anchor rods take the uplift (lapping with additional reinforcement as required).

RE: Design of Column Shear Lugs.

I use 8" long, 3/4" dia. headed studs. If rebar, use ASTM A706, weldable rebar.

RE: Design of Column Shear Lugs.

AISC Design Guide #7 also covers shear lugs.   

RE: Design of Column Shear Lugs.

We have a general note that says all rebar to be welded is to be A706, and that welding electodes for welding rebar are to be E90XX.

RE: Design of Column Shear Lugs.

The grouting problem can be handled with flowable grout. I have had holes drilled in some large plates, over the grout pocket, so that we could be sure it flooded the pocket as it filled the dam.

Michael.
Timing has a lot to do with the outcome of a rain dance.

RE: Design of Column Shear Lugs.

Similar to what Jike and StructuralEIT suggest, why not use a cast in plate with a shearlug?  You don't have to mess with App. D if you do that.

RE: Design of Column Shear Lugs.

For lugs I typically like to use HSS sections. The contractor blocks out using styrofoam.  

RE: Design of Column Shear Lugs.

StructuralEIT: I would love to see your detail.  Could you send it my way?

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