Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: Anchor rods set too low (again!)

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Thanks for the lead for this article.  I talked with AISC Solutions Center today and they referred me to a May 2004 article by Fisher and Kloiber that allows linear interpolation.  I can see the difference; without full engagement of the threads, the specification is not meant, although the nut/rod has some capacity.

Joe Goldbronn wrote:

This exact question was just submitted in the “steel interchange” section of the June 2009 issue of Modern Steel Construction, you can view the magazine for free on their website.  The answer to the question was that it is an all or nothing situation, you do not get reduced capacities for reduced engagement to the nut.

 

Joe Goldbronn, PE

 

 

From: Drew Morris [mailto:dmorris(--nospam--at)bbfm.com]
Sent: Tuesday, June 23, 2009 10:16 AM
To: SEAINT
Subject: Anchor rods set too low (again!)

 

I have a case where the anchor rods have been set too low (again). They are F1554-36 1 1/4" diameter.  To make things worse, the columns have fixed bases and have been installed with the grout below the base plate installed.  I'm not sure why the contractor even bothered to call this in this late. 

Typically, if the rod head is flush with the top of the nut, we use the full strength of the rod. Is there a way to determine what the connection strength is between the nut and the rod if less than the entire rod is engaged?  I can't enlarge the holes in the baseplate for couplers without affecting the anchor rods and I am leery of welding on an extension of the threaded rod.