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

RE: Pre-engineered Bldg Foundation

[Subject Prev][Subject Next][Thread Prev][Thread Next]
When we've used tie-rods on past projects, we've run the tie-rods below the
bottom/slab elevation and anchor them to concrete piers with a vertical
steel plate.  This plate is recessed in a 6" deep pocket on the outside of
the pier which can be grouted solid once the tie-rods have been
pre-tensioned.  The tie-rods themselves are typically encased in concrete,
forming a grade beam between piers, for protection.  The column pier is then
designed to carry the thrust load thru shear from the column base plate
connection (base plate & anchor bolt designs by metal building manufacturer)
down to the tie rods.  

Troy

-----Original Message-----
From: george simmon [mailto:georgesimmon(--nospam--at)yahoo.com]
Sent: Friday, May 11, 2001 2:17 PM
To: seaint(--nospam--at)seaint.org
Subject: Pre-engineered Bldg Foundation


Hi Everyone!
I read with interest the discussion/advice on
"Pre-engineered Metal Buildings" particulary because I
am designing foundations for such a building.  This 
building with a bridge crane produces an outward
thrust of approx. 75 kips.  "Hairpin" is not
recommended to counteract this large outward kick.  I
am told "tie rods" connecting opposite column bases of
the rigid frame would be much preferable.  Now, I have
seen this detail somewhere, including an angle located
just below the column base plate with the anchor bolts
threading thru holes in the angle.  I can't locate
that source now.  I understand "Butler" has a
"Foundation Design and Construction Manual" which
provides some guidance.
Here are my questions:
1.  Has anybody seen this reference?  or, any other
reference which will provide design guidance.
2.  How do you design this angle connection  -  do you
design as a simply supported beam, with concentrated
loads from two AB's and tie-rods acting as supports? 
Seems like I will need several tie-rods at each
column.
3.  What kind of pre-tension do I need to specify in
the tie-rods?  Would a 10% pre-tension of the
allowable capacity of the tie rods be adequate?  
4.  I assume turn-buckles in the tie-rods would be
used for this purpose.  How do we measure the
pre-tension?
5.  Would you locate the tie rods within the slab or
below the slab?

Thanks for your precious guidance/advice to keep me
out of trouble.


 

__________________________________________________
Do You Yahoo!?
Yahoo! Auctions - buy the things you want at great prices
http://auctions.yahoo.com/

* 
*   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 

* 
*   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