Need a book? Engineering books recommendations...

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

RE: CONCRETE: Repair of Segmental Post-Tensioned Concrete Tank

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Sounds ugly. If the only problem is leakage, I would go with a liner. The
repair experts tell me it is almost impossible to fix a bad existing
injection job.

-----Original Message-----
From: Bill Polhemus [mailto:bill(--nospam--at)polhemus.cc]
Sent: Thursday, July 28, 2005 9:50 AM
To: seaint(--nospam--at)seaint.org
Subject: CONCRETE: Repair of Segmental Post-Tensioned Concrete Tank


Hi, folks.

I have a weird one here: A Post-Tensioned tank that was done back in the
70s or thereabouts. The weird thing about it is, that it we done using
essentially tilt-up panels with ducts cast into them horizontally, then
threaded together with PT cables that were then tightened and the
anchorages (such as they were) grouted into pockets occasionally occurring
in the panels.

Then, the joints between the panels were grouted.

As you might guess, those joints are the problem: Over the years they've
continually leaked. You can see where urethane injection has been employed
numerous times (the injection ports / packers are still in place with
dried urethane oozing out of them--it's really an ugly mess).

The contractor that provides the occasional injection reports that they
cannot get any more urethane in, it just "won't go" any more.

So now the client wants alternative methods of repair. I'm on record as
saying that I believe the tank must be replaced, that repair would be
costly (probably requiring, say, a rubberized or otherwise flexible tank
liner together with, say, a new shotcrete shell--possibly requiring some
repiping.

And even then I'm not sure that the thing would last indefinitely.

Anyway, are there other repair schemes available to anyone's knowledge?
One thing to keep in mind is that I'm pretty certain the existing tank
walls need to be discounted for strength. If they're not already pretty
much "shot," it's only a matter of a short time until at least one of the
panels will "go." It's kind of a scarey situation.

Anyway, I think the client's onsite management would be quite happy to
entertain notions of replacing the tank altogether.

Comments?

Thanks in advance.


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


This e-mail is intended to be delivered only to the named addressee(s) and
may contain information that is confidential and proprietary.  If this
information is received by anyone other than the named addressee(s), the
recipient(s) should immediately notify the sender by e-mail and promptly
delete the transmitted material from your computer and server.  In no event
shall this material be read, used, stored, or retained by anyone other than
the named addressee(s) without the express written consent of the sender or
the named addressee(s).



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