] [Thread] [Date] [Author]

[Daryl Richardson <h.d.richardson(--nospam--at)shaw.ca>]

Roger,

        There were some gluelam failures in Canada about the same time; but, as I
remember (I could be mistaken) they were limited to one company and were failure
of the glue not failure of the wood.

Regards,

H. Daryl Richardson

Roger Turk wrote:

> Tom Skaggs wrote:
>
> . > The NDS commentary covers the topic pretty well.  I'll paraphrase.... if
> . > the material is clear grain, check and shake free, "the tension perp
> . > design value may be considered as about one-third the shear design value
> . > parallel to grain". As the NDS Commentary further says, "undetectable
> . > ring shake and checking and splitting that can occur as a result of
> . > drying in service, very low strength values for this property can be
> . > encountered in commercial grades of lumber".
>
> . > Good luck....
>
> . > Tom
>
> This is the same requirement for radial tension stresses in GLBs, *except*
> for DF!  Curved GLBs in a roof over a gymnasium designed by the Structural
> Engineer to these requirements (as permitted in the 1967 UBC) started failing
> in the late 1960s.  GLB fabricators told the contractor that when *they*
> designed curved GLBs, they limited radial tension in DF to 15 psi.
>
> A paper presented at an SEAOC convention in the early 70s discussed this and
> opined that the presenter considered even 15 psi too high.
>
> A. Roger Turk, P.E.(Structural)
> Tucson, Arizona
>
> ******* ****** ******* ******** ******* ******* ******* ***
> *   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 
******* ****** ****** ****** ******* ****** ****** ********