Seepage in Water Retaining Structure

Hello Ramprasad Reddy

I presume your structure is 29m x 15m x 6m deep.

If not please advise.

You refer to "bricks". Are you meaning "Concrete precast standard blocks"?

The use of standard bricks for a 6 metre head of water is not going to be satisfactory long term, as I would expect failure with the pressure on the mortar joints of the bricks.

The thermal expansion rate of bricks is quite different from Reinforced concrete, and that may well be the cause of the seepage.

Depending on what the structure is intended to hold, and the amount of seepage, if it is holding water, it may be possible to use waterstop paint (Check your local paint Makers) which is a special high cement based paint which can seal against a head of water - you paint it on from outside the tank, and after it "dries" some water leak has reduced, then repeat the process as required, until no further seepage occurs..

Is the brickwork anywhere else seeping at other joints, or only round the edges against the Reinforced Concrete?

If only around the edges, the problem is either:

1. Thermal difference of expansion, which is not easily to be solved if you want to retain the bricks
2. Lack of proper bonding of mortar to the concrete.

If the brickwork is to remain, for reasons of beauty, for long-term safety it is best to drain the tank, and fit a reinforced concrete wall behind the brick wall, ensure that this new wall is properly bonded when the concrete pour takes place.

Then, in case of any small leaks, drill a few holes through the base mortar of the brick wall, so that any seepage is quietly drained away.

Advise further here, with

Kind Regards....

Thanks for your reply and the seepage is only round the edges against the Reinforced Concrete.

Regards

Ramprasad Reddy

Please let us know the brand name if any?

Regards

Hello again, Ramprasad Reddy

I just tried as search terms in Google: paint waterstop

Have a look at: http://www.dice-inc.com/dailynews_sept_2005.pdf

That weblink gives the description and address details of a similar product to what we used here in New Zealand, with great success.

We used to purchase Waterstop paint made in New Zealand by Levenes Paints Ltd, but sadly, that paint manufacturer went into receivership some 20 years ago.

Alternatives would be: http://paint-and-supplies.hardwarestore.com/50-276-concrete-patch/quikrete-hydraulic-water-stop-cement-105404.aspx

The Quikrete immediately above is not a product I have actually used, but the specifications look OK.

Because the products are heavy, it would be cheaper if you could locate a local supplier for the above sort of paint on sealer.

Follow the instructions for either product carefully, and the paint must be stirred during use, (you will need an electric motor stirrer), or the heavy components sink to the bottom of the container, and the work is then not satisfactory.

But, if time is of the essence, airfreight may be a better option, and you could have it on the job within a few days.

You did not advise whether bricks or concrete blocks.

Nor did you advise water height.

Advise your progress here, thanks.

Kind Regards....

Hello sir,

We had used bricks not concrete blocks and the height of water is 5.5m.

Regards

Hyydraulic cement should be able to seal the seepage without dewatering. Also, possibly coating with paint like UGL Drylock or using a crystalline waterproofer like Xypex would also help solve the situation.

www.mountaingrout.com look at the injection urethane products such as "Flex"

Capillary Crystalline Reactive products--as AMAZING as they are--will not work unless all components are portland cement based as these react with constituents of the initial hydration process to form a crystalline structure within the concrete.

Rich mixes of cement and rubberized paint products such as have been suggested may work until there is movement--and there always is

I assume that the term "RCC" means reinforced concrete construction. Why did you use brick as a structural material for one wall in a water retaining structure? Would it not have been better to design a reinforced concrete tank (four walls and a floor), then add brick veneer on one wall if aesthetics are a concern? That way, you have a proper water retaining structure without relying on brick. The brick would be a non-structural element, added only for its appearance.

It is difficult to provide you with a solution to minimize seepage without knowing how your brick wall is reinforced and how it is connected to the concrete walls. If the brick wall is adequately reinforced, there are a number of products which might be considered in reducing water seepage. But if the joint between brick and concrete permits too much rotation, none of these are likely to work very well.

One such product is Xypex. Another is Krystal. These work well in reinforced concrete tanks, but I cannot say how well they will work in your situation.

Sorry, that product should be spelled Krystol, not Krystal. Another one I have used is Vandex. These products have all behaved well in my experience. They all work on the principal that leaks in the structure will eventually be closed by crystalline deposits attaching to the concrete and reducing the pore size. Over time, the size of the pores diminishes until the water ceases to flow. Other concrete waterproofing products may be found at this site.

I do not have any experience with brick walls retaining water, so I don't feel particularly confident in recommending any of these products. On the other hand, I cannot think of anything I would rather rely on than the above named products. But if the initial pores are very large, it would take a long time before they would provide a satisfactory seal.

In my experience, hydraulic testing of reservoirs has produced leakage volumes within specified limits upon completion of construction. Most reservoirs will leak a bit due to the porosity of concrete or joints not fully sealed with pvc waterstops. With Xypex, Vandex or Krystol, the leakage will diminish with time. In older reservoirs, properly waterproofed, the leakage should be negligible.