Need a book? Engineering books recommendations...
RE: single plate shear connection edge distances[Subject Prev][Subject Next][Thread Prev][Thread Next]
- To: "'seaint(--nospam--at)seaint.org'" <seaint(--nospam--at)seaint.org>, Steel Detail <steel-detail(--nospam--at)yahoogroups.com>
- Subject: RE: single plate shear connection edge distances
- From: "Carter, Charlie" <carter(--nospam--at)aisc.org>
- Date: Sun, 3 Nov 2002 08:21:35 -0600
>I'm trying to confirm the plate dimensions to be used for single plate shear
>connections using 1" diameter bolts. Table J3.4 of the latest AISC Manual
>page 16.1-63 (I'm actually looking at the LRFD 3rd edition - I can't believe it
>either) indicates 1 3/4" at sheared edges (1 1/4" at other edges) with a note
>that says 1 1/4" is permitted at the ends of beam connection angles and
>shear end plates. I assume that they really mean "shear end plates" and
>not just "shear plates", but could be wrong.
In general, this is correct. The note is specifically applicable to angles and shear end plates. I tried to get it more general, but it was noted that single plates (shear tabs) have special design procedures that some might use and get confused if the note were expanded to single plates as well.
The reality is that the historic note, which stemmed from a time when there were no bearing terout calcs, is probably not needed any more. We can calculate what the tearout strength is now, so that is the direction I'm headed. If I'm successful, the minimum edge distance table will only apply perpendicular to the line of force, not in the direction. In the direction of force, the calculation will control. Of course, the table still provides good practice minimums. And of course, this is all still academic as it is not approved by the AISC Committee on Specifications.
>The single plate shear connection tables for 1" bolts use plate lengths
>that assume a 1 1/2" edge distance in both directions. Was the note
>in table J3.4 intended to include shear plates as well as shear end plates
>or is it OK to assume that plates are not sheared? The problem is similar
>for the 1 1/8" bolts, but the note does not apply to 1 1/8" bolts.
The term "shear end plate" is used to differentiate from "moment end plates", not to include shear tabs. Nor is it intended to distinguish between sheared and flame-cut plates.
>The tables also indicate that they are applicable to short slotted holes.
>For 1 1/8" diameter bolts in short slotted holes at a sheared edge, according
>to Table J3.4, the edge distance would be 2" and I would add 3/16" for the
>slot according to Table J3.6, resulting in and edge distance of 2 3/16", but
>the tables are using 1 1/2". What is the piece of the puzzle that I am missing?
Right you are, but the single-plate connection design tables in the Manual are based upon the Asteneh procedure, which was developed from Hassan Astaneh's testing. He used 1 1/2" edge distances in all his tests and found good performance. One aspect of his approach is to use plate deformations, including arching of the edge of the plate at the holes as the bolts bear, to provide ductility. The 1 1/2" dimension makes it easier to achieve this.
- Prev by Subject: RE: single plate shear connection edge distances
- Next by Subject: Slab bands
- Previous by thread: RE: single plate shear connection edge distances
- Next by thread: RE: Yet another email regarding the dreaded ADA