Need a book? Engineering books recommendations...

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

RE: Aeroplane Hanger

[Subject Prev][Subject Next][Thread Prev][Thread Next]
I also agree with the new piers and foundations approach.  One thing to
watch for if you go that route is the large horizontal force usually
associated with the connection of the rigid frames to foundations.
There may be a tension tie somewhere below the slab that now ties the
frame together at the base.  You will have to design the new piers to
resist the load currently resisted by the tie (if one is there).  If you
have existing drawings of the building (by the PEMB manuf) then I would
contact them to see what loads they originally designed to.  

I am probably telling you things you already know, but just wanted to
caution you on the large horizontal forces you will likely deal with.  

Timothy R. Campbell, PE

-----Original Message-----
From: Blomberg, Paul [mailto:Paul.Blomberg(--nospam--at)jacobs.com] 
Sent: Wednesday, December 11, 2002 2:24 PM
To: 'seaint(--nospam--at)seaint.org'
Subject: RE: Aeroplane Hanger

I agree with the concrete piers and foundations approach.  The existing
foundations may not work for the new height and might require
remediation.
Lifting the structure is not that difficult.  Temporary support and
working
under the monster might be interesting!

Paul Blomberg
Phoenix, AZ


-----Original Message-----
From: Daryl Richardson [mailto:h.d.richardson(--nospam--at)shaw.ca]
Sent: Wednesday, December 11, 2002 11:08 AM
To: seaint(--nospam--at)seaint.org
Subject: Aeroplane Hanger


Fellow engineers,

        I have been asked to provide engineering services for the
lifting of an aeroplane hanger roof by ten feet.  This sounds like the
kind of interesting, tricky, challenging problem that I would like to
take on.

        My question is: how would one proceed to physically do the work
in the field, keeping in mind that not only must it be done but it must
be done safely?

        The building is a pre engineered rigid frame steel building 120
feet square by about 18 feet high with tapered beams and columns.  There
is a horizontal bolted joint between the columns and the beams.  It has
five rigid frames including the doorway wall plus an end wall consisting
of seven columns with beams running continuously over the top.  The door
is sectional, moving sideways, and is supported on wheels running on
tracks cast into the floor.  Building a taller door would also be
required.  There are "lean-to" type structures on both sides which are
lower than the main hanger roof and which appear to have been part of
the pre engineered package.  The building is 25 plus years old and
appears to be in excellent condition.

        Design wind for the area would be equivalent to a peak 85 mph
gust and design ground snow load would be 20 psf.  Seismic is
effectively 0.  Construction time would be Feb/Mar.

        One contractor's proposal (very preliminary, in fact discussion
only) is to secure the roof with cable or rod bracing against wind; use
adjustable telescopic columns to support the roof; jack each column in
sequence a few inches at a time until ten feet is achieved; insert
prefabricated column sections into place and bolt it down; finally
reinforce the frames for the new design loading (I know from past
experience that pre engineered buildings have virtually no reserve
strength so substantial reinforcement will be required).

        Any other ideas would be appreciated.

Regards,

H. Daryl Richardson

========================================================================
==============
NOTICE - This communication may contain confidential and privileged
information that is for the sole use of the intended recipient. Any
viewing, copying or distribution of, or reliance on this message by
unintended recipients is strictly prohibited. If you have received this
message in error, please notify us immediately by replying to the
message and deleting it from your computer.

========================================================================
======


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