Need a book? Engineering books recommendations...

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

Re: SEI wind design example

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Bro

am I lazy or what? I sent your Q to SEAONC
Here is what I got

Love Bro

Horizontal roof pressures either cancel or as you suggest oppose the over
turning from the wind ward wall pressure. Therefore ignoring should be
conservative.

Ignoring dead load should be conservative. As it is for limit state design
we use the 5th percentile estimate of the dead load, rather than the 95th
percentile: eg. minimum estimate of dead load, and lowest value of all is
zero: ignore resistance.

As for uplift. Uplift and lateral bracing considered separately and combined
as necessary. For example if trusses are tied down at each end, then roof
uplift may not add to hold-down in the transverse shear walls but may add to
hold-down for longitudinal shear walls. So the designer adds the direct
uplift force in as required.

Or at least that is my guess.



Regards
Conrad Harrison
B.Tech (mfg & mech), MIIE, gradTIEAust
mailto:sch.tectonic(--nospam--at)bigpond.com
Adelaide
South Australia

# From: ken ng <zy7up(--nospam--at)yahoo.com>
Does any one know where I can find similar design example like this for ACI-318-05 or 07?
TIA



David Merrick, Structural Engineer, Merrick Group wrote:
For the wind design method: Trial Design Problem: Prob_01_07, found at the web site:
content.seinstitute.org/files/pdf/Sol_Prob_01_07-Final.pdf

On page 4 they show a profile of the wind loads and a shearwall. They neglect the horizontal component of the roof pressures since the reduce the lateral force on the wall. How come they ignore the vertical uplift force from the roof too?

The same is done on page 3.

Since they neglect dead load, perhaps they assume the tow counteract each other.

David Merrick, SE



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