To: "'seaint(--nospam--at)seaint.org'" <seaint(--nospam--at)seaint.org>
Subject: RE: general bolt questions
From: Scott Maxwell <smaxwell(--nospam--at)engin.umich.edu>
Date: Fri, 9 Feb 2001 13:35:31 -0500 (EST)
I am used to typically using 3/4" bolts. I have, however, used 1"
diameter bolts. The only recommendation that I offer is that you either
use all one size on a job or if using multiple sizes, don't use sizes
within 1/8" of either (i.e. don't use 3/4" and 7/8" on the same job).
Bolts that are within 1/8" of each other in the diameter can be confused
with each other and potentially installed at the wrong location. It is
much more difficult to confuse a 3/4" and a 1" diameter bolt.
With regard to the edges distances, I can't give a "solid" answer since my
steel books are at home (I am now at a primarily concrete oriented job,
and haven't bothered to bring in my steel books...yet), but I can
speculate. Minimum edge distance is a function of bolt diameter and edge
condition (i.e. is it a sheared or rolled edge). It is possible that the
example in the connections manual is "assuming" a rolled edge (rolled
edges require a small minimum edge distance if my memory serves me
Hope that helps,
> -----Original Message-----
> From: Mark Pemberton [mailto:Markp(--nospam--at)lbdg.com]
> Sent: Thursday, February 08, 2001 3:03 PM
> To: 'seaint(--nospam--at)seaint.org'
> Subject: general bolt questions
> We typically use 3/4" diameter bolts for beam to column and
> beam to beam connections, but are considering going to 1"
> diameter bolts. What is the typical industry standard?
> We have also noticed an inconsistency within the AISC LRFD
> manual (2nd addition) for the top and bottom minimum edge
> distance for bolts at a shear tab. Table J3.4 requires for 1"
> diameter bolt, 1-3/4" edge distance for a sheared tab while
> figure 9-15 of Vol 2 (the connections manual) shows an allowable
> 1-1/2" edge distance. How is this typically resolved?
> Mark Pemberton, P.E.
> Lionakis Beaumont Design Group