Best waterproofing method
Best waterproofing method
(OP)
good day...
we are to construct again a water storage tank; this time, a 2-basin reinforced concrete water storage tank. one chamber will hold sludge from "blowdown" operation of water clarifiers and the other chamber will hold the treated water. what could be the best waterproofing method to prevent possible seepage and contamination to the treated water?
thanks in advance for any suggestions & recommendations...
we are to construct again a water storage tank; this time, a 2-basin reinforced concrete water storage tank. one chamber will hold sludge from "blowdown" operation of water clarifiers and the other chamber will hold the treated water. what could be the best waterproofing method to prevent possible seepage and contamination to the treated water?
thanks in advance for any suggestions & recommendations...





RE: Best waterproofing method
It is not acceptable to have a waste tank separated from treated water with just a common wall between the two waters.
You will find phrases such as "Design shall prevent cross connections and there shall be no common walls between potable and non‑potable water."
The answer is to design 2 separate tanks with an air gap between. You should also seal the concrete tanks. Contact Tnemec for a coating recommendation.
RE: Best waterproofing method
when you say "air gap" would a 2" gap between the RC walls of the two tanks be enough?
RE: Best waterproofing method
If you're tight on space, I would still make the gap no less than 2'-0". That should give enough room to build forms and get them out.
Unless the sludge has a corrosive component I wouldn't coat the concrete. Your best water proofing method is 12 inch walls, waterstopped joints and good workmanship.
RE: Best waterproofing method
RE: Best waterproofing method
yes bimr, air gap i mean also a 2nd wall a few inches away from the 1st wall.
since there is a space limit for the required volume of the sludge tank, i am thinking of a 0.40-m gap enough to give space for waterproofing works..my next concern would be : the tank are covered with suspended slab, that includes the "gap" between then. shall i install an air vent for the said gap?
RE: Best waterproofing method
RE: Best waterproofing method
one crazy idea had popped up from my not-so-brainy head : how would you think if i would consider that there wont be a gap anymore? the 1st wall shall be the form siding for the 2nd wall. first i will pour concrete for the 1st RC wall then after form-stripping & waterproofing of the face adjacent, will do the formworks and concreting of the 2nd RC wall...
would that be acceptable in engineering practice?
RE: Best waterproofing method
We work in the water and wastewater areas exclusively. Our saying is if you have a 4,000,000 gallon reservoir full of potable water and add one drop of sewage, what do you have? 4,000,000 gallons of sewage.
RE: Best waterproofing method
Another consideration should be for the piping. You have to allow space for the piping as it enters and exits tanks.
RE: Best waterproofing method
anyway, thank you very very much guys for the info and recommendations...they helped a lot...
RE: Best waterproofing method
if, may i seek your idea on the actual volume of poured concrete versus the estimated theoretical volume as referred from the construction drawings...
could there be any difference between them? sometimes i get this estimated volume of readymix concrete and then during the actual pouring, there is a deviation, ie: the actual poured volume is somewhat greater than the estimated volume..
how was that? could there be a sort of factor to be used in the estimated volume to achieve the "actual" volume?
what are some factors to be considered in estimating the volume of concrete to be poured, if there are any??
RE: Best waterproofing method
RE: Best waterproofing method
RE: Best waterproofing method
RE: Best waterproofing method
RE: Best waterproofing method
these would help us a lot...
RE: Best waterproofing method
could anyone provide a sample computation in determining the weight of aggregates (washed sand and crushed G-3/4 gravel) per volume of concrete for a 3500psi capacity at 28days?
please include also the number of liters of water for every volume of concrete.
thank you