Need a book? Engineering books recommendations...

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

Re: Wood Dowels embedded in concrete

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Buddy,

So, am I correct in assuming that you would use the concrete embedment
depth for lm in the Mode Im equation then (I suppose I could be a good
little boy and check TR12, but decided to be lazy and just ask)?

Thanks,

Scott
Adrian, MI

On Fri, 12 Nov 2004, AWC Info wrote:

> Jim/Scott,
>
> Nels already recommended TR12, which is a good reference for this question
> if you don't have the 2001 NDS.
>
> However, wrt the suggestion to ignore certain equations in the 2001 NDS,
> this is incorrect. We consolidated all the connection equations in the 2001
> NDS (based on TR12) and now all equations must be checked for different
> dowel-types. There is no longer the option to ignore certain yield modes for
> certain fasteners and materials.
>
> Note that all equations except 11.3-2 use Fem (concrete dowel bearing
> strength) in some fashion (note the k1, k2, k3 and Re equations), so these
> yield modes cannot be ignored.
>
> There's a paper describing the changes to the 2001 NDS on our website:
>
> http://www.awc.org/Publications/papers/NDS2001article.pdf
>
> HTH
>
> Buddy
>
> John "Buddy" Showalter, P.E.
> Director, Technical Media
> AF&PA/American Wood Council
> 1111 19th Street, NW, Suite 800
> Washington, DC 20036
> P: 202-463-2769
> F: 202-463-2791
> http://www.awc.org
>
> The American Wood Council (AWC) is the wood products division of the
> American Forest & Paper Association (AF&PA). AWC develops internationally
> recognized standards for wood design and construction. Its efforts with
> building codes and standards, engineering and research, and technology
> transfer ensure proper application for engineered and traditional wood
> products.
>
> *********************
> The guidance provided herein is not a formal interpretation of any AF&PA
> standard.  Interpretations of AF&PA standards are only available through a
> formal process outlined in AF&PA's standards development procedures.
>
> *********************
>
>
>
> From: Scott Maxwell <smaxwell(--nospam--at)engin.umich.edu>
> To: seaint(--nospam--at)seaint.org
> Subject: Re: Wood Dowels embedded in concrete
>
> Jim:
>
> Section 8.2.3 of the 1997 NDS might help some.  It seems to give some
> guidance on how the Table 11E (and the similar if not identical table 8.2E
> in the 1997 NDs) are determined.  According to section 8.2.3 of the 1997
> NDS, you are to use the lesser of Equations 8.2-2, 8.2-3, 8.2-4, 8.2-5 and
> 8.2-6 (which equate to 11.3-2 through 11.3-6 in the 2001 NDS).  You use
> the dowel bearing strength of the concrete or masonry for Fem and it
> appears the embeddment depth of the masonry for tm or lm (note that since
> you don't use Equation 8.2-1/11.3-1, then the only Equation with tm/lm is
> 8.2-4/11.4/-4).
>
> HTH,
>
> Scott
> Adrian, MI
>
>
> On Thu, 11 Nov 2004, Jim Wilson wrote:
>
> > NDS Table 11E is for single shear sawn lumber bolted to concrete with an
> embedment of 6" or greater.  For a case with less than 6" embedment, is
> there some sort of an adjustment factor to determine the capacity?  For a
> paltry couple hundred pounds of loading, is a 6" embedment any different
> than a 3" or 4" embedment?
> >
> > Or is it perhaps acceptable to use either Table 11J for lag screws or
> Table 11A for bolts, hopefully as a conservative backup?  Table 11A would be
> a much better value, but then what would be the thickness for the main
> member?  It might be reasonable to use a large thickness for the main member
> to better model the concrete, but that might be a real stretch.
> >
> > Jim Wilson, PE
> > Stroudsburg, PA
>

******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
* 
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) or UnSubscribe, please go to:
*
*   http://www.seaint.org/sealist1.asp
*
*   Questions to seaint-ad(--nospam--at)seaint.org. 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: http://www.seaint.org 
******* ****** ****** ****** ******* ****** ****** ********