Need a book? Engineering books recommendations...

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

RE: Aeroplane Hanger

[Subject Prev][Subject Next][Thread Prev][Thread Next]
If the building is raised to be on 10 foot high piers, the lateral
flexibility of these piers and how it may reduce the strength of the roof
for gravity loads may be an issue. For a large thrust, there may be
significant lateral deflection at the 10 foot elevation. I believe the PEMB
frames are designed as if there is no lateral movement at the base.

It may be worth checking out.

Jim K.

-----Original Message-----
From: Effland, Greg [mailto:geeffland(--nospam--at)butlermfg.com]
Sent: Friday, December 13, 2002 10:20 AM
To: seaint(--nospam--at)seaint.org
Subject: RE: Aeroplane Hanger


Daryl,

Sorry for the late response as I was out of the office.  Looking through the
many comments that were sent in it appears a few important items were left
out.

1) Raising the building an additional 10 ft above the ground elevation will,
per code, increase the wind loads on the building.  This will cause the
horizontal reactions and possibly the vertical reactions under wind loading
to increase.

2) Assuming higher loads, this will increase the moments and shears on the
frames lending BOTH the columns and roof beams to have potential over stress
issues.

3) Changing out the columns for new longer columns could also significantly
change the moment diagram for the frame causing the roof beams to be over
stressed as well.

4) If the roof or wall systems (panels and secondaries) are partially or
completely removed during the attempt to raise the building then additional
temporary bracing may be needed.

5) A rehab of the older building may require you to "design" the building
for newer codes and loadings.  This may be enough by itself to over stress
the building (theoretically at least).

A lot of the comments previously posted were good ideas.  I would tend to
think that the 10 ft concrete piers might be the better idea. It still has
some of the above issues though and I think that might be an expensive
option...  Check costs, if might be better and/or cheaper to replace the
building as someone had mentioned.

Lowering the floor may get around the building modifications and the
increased wind loads.  May still have to check for the newer building
code... might want to check on that one.

Depending on job particulars and whether or not it is a Butler Building the
steel is most likely between 42 and 50 ksi in yield strength.

Here is some contact info for the Canada office that might be of assistance
for you:
Butler Buildings (Canada)
3070 Mainway Drive, Unit 21
Burlington, ON, Canada L7M 1A3
Phone: 905-332-7786


Hope this helps,
Greg Effland, P.E.
KC, MO USA

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