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Re: Wd: Oversized holes in sill plates

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Livingston, Michael wrote:

> Does anyone have any data for allowable loads in sill plates that have
> been drilled larger than 1/16th inch over the diameter?  We're
> investigating an existing building, and the proposed fix is to add
> epoxy
> in the bolt-holes.  As this can be an expensive prospect, I'm curious
> if
> there are some reduced values for different sizes of overdrilling.
> Any
> help/opinions would be appreciated.
> Also, does anyone have any opinions on the epoxy fix?  Do holes that
> are
> only a bit overdrilled pose a problem for getting the epoxy to fill
> the
> hole to the bottom?
> Mike Livingston, S.E.

I've never tested specimens with this specific defect but it has always
been my feeling that "epoxy" would be a suitable repair.  If you don't
think the epoxy will fill maybe the gap is too small to worry about.
Hilti & ITW-Ramset/RedHead both make products that will probably work
but are not necessarily "approved" for this use.

Mechanical fixes that exist depend on anchor bolt diameter, 1/2" might
be subject to too much bending, 5/8 & 3/4 might be better.  Simpson
makes a rectangular plate that drops over the anchor bolt (tight fit) &
is then secured to the sill with self-drilling "lags".

A much more positive fix is to use a deep socket style cutter (like
Milwaukee Steel Hawg cutter), get one were the id just fits over the
anchor bolt.  The cutter will "pilot" over anchor bolt & cut a new
hole.  Take care not to drill too deep (will ruin the carbide teeth on
the concrete).  Lost cost "bushings" can be made from the appropriate
size tube or pipe.  Drop the bushing over the anchor bolt, cover with
square washer & you're done.

 Robert Kazanjy, PE  **Disclaimer: I speak for myself not UC-Irvine**
 Senior Development Engineer
 Civil & Environmental Engineering
 UC Irvine
 E4130 EG,  Zot: 2175