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Re: Water reservoir - joints, wall ties, and alternate pours

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I know that these kind of snap ties are used in elevated pools.  There are the same standard snap ties except they add to them the water stopper.  A good shell contractor should know that a water stopper should be required when used in your application.
Try Medow Burke they are in Tampa the Tel, # is 1-800-282-7213.  Just for curiosity why are you concern about where to get them.  It is the G.C.'s if you specify it in the specs.
About the bond breaker, what I was thinking if you must use separate structures you might as well seperate them.  From my experience an expansion joint is required every 200 feet in a structure. In your case you will be pouring 180' of concrete walls,  the biggest concern is the shrinkage which take place up to 90 days before it level off.  I would use a cocncrete mix with a retarder.  You might want consult with your local conc. mixing companies to see if the have any special mixes for this type of use.
Please let me know what you decide to use.  I know I am not been much of a help but it is good to throw in ideas.
----- Original Message -----
From: Kevin Below
Sent: Thursday, March 28, 2002 9:33 AM
To: seaint(--nospam--at)
Subject: Re: Water reservoir - joints, wall ties, and alternate pours
Thanks for the advice, Ibrahim. 
Where can I get info on snap ties with water stoppers?
I have never seen them, and I can't find them on the web.

Why would you use more than a bond breaker between the walls?  Do you
think that just the bond-breaker will not suffice to force a crack


From: "Ib sa" <ieseng(--nospam--at)>
To: seaint(--nospam--at)
Subject: Re: Water reservoir - joints, wall ties, and alternate pours

Snap ties with water stoppers should be used for the wall forming. Also
would use more than a bond breaker between the walls maybe 1 to 2

>From: "Kevin Below" <kevin.below(--nospam--at)>
>Reply-To: <seaint(--nospam--at)>
>To: <seaint(--nospam--at)>
>Subject: Water reservoir - joints, wall ties, and alternate pours
>Date: Thu, 14 Mar 2002 17:47:31 -0500
>I am designing my first water-retaining structure - a series of 3
>underground rectangular tamks, each 20m x 20m x 2.5m deep with 355mm
>(14") wall thickness. We have 60 degrees Celsius range of temperature
>here in Quebec. The total length is thus 60m, which is a long way to go

>without joints. But I would like to avoid joints like the plague, so I
>have elected to use a separate structure for each tank. So I have a
>double-wall between the tanks, with the intention to pour the walls of
>one tank, apply a bond-breaker on the face of the common wall, and then

>pour the second tank, and so on.
>I don't like it, because it complicates the wall ties for the second
>wall of the double-wall section. And then I have to cover the joint
>with flashing to keep out the water in our freeze-thaw climate. But the
>experts in my books seem to agree that no joint is a good joint,...
>maybe construction joints are a necessary evil and can be done well.
>What do you think? Is it better to separate the tanks as I have
>proposed, or to simplify the construction and add a joint or two ?
>What do you do with the wall ties ? Do you use conical ends, and patch
>the holes? Will non-shrink grout do the trick?
>What about pouring the wall in alternate sections, leaving short
>sections to infill after a week or two? Is it worth it?
>I have been researching this and doing my calcs for 3 days now, and I
>have accumulated a lot of notes from my references, but they can't
>answer everything I guess... I have heard horror stories of engineers
>in court because of leaky tanks, so I am very wary. One reference I
>use is in a chapter on water-retaining structures by B.P. Hughes at the

>University of Birmingham. He mentions the importance of limiting crack
>widths to 0.1mm (0.004"), which usually controls the design. And so it
>does in this case. Steel stresses are way down at about 50 MPa (7,000
>psi). Interesting. It's very different from buildings.
>Kevin Below
>Génécor inc., experts-conseils

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