Need a book? Engineering books recommendations...

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

Re: Vierendeel truss in wood

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Neil:

Figured on deflection being an issue.  The company that I work went in an
did a repair on a similar style truss that was suffering from deflection
issues.  Don't know how similar they were.

Regards,

Scott
Adrian, MI


On Wed, 8 Sep 2004, Neil Moore wrote:

> Scott:
>
> I've done a number of Vierendeel trusses and one of the biggest problems
> was deflection.    In my freshman year at Cal Poly some seniors built a
> Vierendeel truss out of wood with steel tension rods and plywood panels
> with a wood compression chord.  Don't think the span was very long.  It was
> pretty neat; I remember all of them hanging off the thing.  (this is
> 1951!)   I think that your truss would be pretty springy.
>
> Neil Moore, S.E.
> shingle springs, ca
>
>
> At 07:19 PM 9/8/2004 -0400, you wrote:
> >I have project where the architect would like to create/use a Vierendeel
> >truss out of timber/glulam members.  I thought that I would get others
> >thoughts as my gut is not giving me the "warm fuzzies" (I am in the
> >process of creating a model to determine what kind of moments I would
> >dealing with at the connection of the vertical members to the top and
> >bottom chords, so I only have my gut at this point).
> >
> >The configuration proposed is basically comprised of two 15" deep by 5
> >1/8" wide glulams as the top and bottom chord.  At three places along the
> >span there are three vertical timber members that are spaced about 6" or
> >so apart (i.e. three locations of three vertical members each).  The
> >connection of the vertical members (9 members total in groups of three) is
> >done by way of a vertical row of two bolts/pins.  The vertical members are
> >about 4" to 6" wide (don't totally recall and don't have the drawings
> >right in front of me).  The span of the truss is on the order of about 32
> >ft.  The truss is carrying about 6 foot (horizontal projection of 12/12
> >roof) tributary width of stick framing roof joists.  The ground snow load
> >will likely be on the order of 25 psf.
> >
> >Now, I know wood is not really that great for "moment connections".  But,
> >I also know that there will be some rigidity there from how this will be
> >put together.  I am just not completely sure how much I can count on (and
> >don't know yet how much I will really need until I run the model).
> >
> >Oh, likely DougFir...if it matters.
> >
> >Any thoughts?
> >
> >Thanks,
> >
> >Scott
> >Adrian, MI
> >
> >
> >******* ****** ******* ******** ******* ******* ******* ***
> >*   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
> >******* ****** ****** ****** ******* ****** ****** ********
>
>
>
>
> ******* ****** ******* ******** ******* ******* ******* ***
> *   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
> ******* ****** ****** ****** ******* ****** ****** ********
>

******* ****** ******* ******** ******* ******* ******* ***
*   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 
******* ****** ****** ****** ******* ****** ****** ********