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

RE: x-bracing connections

[Subject Prev][Subject Next][Thread Prev][Thread Next]

X-bracing can be a problem, but is easily fixed.  Many savvy detailers will
detail X-braces 1/8" short, and use 2 bolts at each end as a minimum.  Then
the iron workers will drive bull pins (or drift pins depending on the iron
worker regional jargon) in the outboard holes to line up the second hole and
install the bolt.  The bull pin is then removed and the other bolt is

Another approach is to use over sized holes in the gusset and use a slip
critical connection.  This is a good solution when you have a lot of bolts
and claw angles where fit up can be problematic, but is over kill for only a
little L 3x3x1/4 X-brace.

Tell the iron workers that if they knew ANYTHING about hanging iron there
should be no problem.  Oh yeah, then you need to run like hell!!

Harold O. Sprague

> -----Original Message-----
> From:	Ron Hill [SMTP:ronhill(--nospam--at)]
> Sent:	Tuesday, February 05, 2002 11:32 AM
> To:	Seaint@Seaint. Org
> Subject:	x-bracing connections
> I have a client that says he has problems in the field with bolting
> x-bracing.  The diagonals are generally 3x3 x1/4 angles bolted to gussets.
> The holes are 13/16" diameter predrilled for 3/4" bolts.  They claim that
> the holes never align.  They want to maintain an all bolted erected
> structure and welding the angle to the gusset is not an option.
> Has anyone had this problem with miss matched holes??  They claim the hole
> locations are correct based on shop drawings but they think tolerances
> cause
> the problem.
> Ronald Hill, P.E.
> HILL Consulting Engineering
> PO BOX 26525
> Birmingham, Alabama 35260 USA
> Phone: 205.823.4784
> FAX: 205.823.4145
> Email: ronhill(--nospam--at)
> Efax: 509.275.8095
> http:\\

******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at:
*   This email was sent to you via Structural Engineers
*   Association of Southern California (SEAOSC) server. To
*   subscribe (no fee) or UnSubscribe, please go to:
*   Questions to seaint-ad(--nospam--at) Remember, any email you
*   send to the list is public domain and may be re-posted
*   without your permission. Make sure you visit our web
*   site at:
******* ****** ****** ****** ******* ****** ****** ********