does pool water used to make a concret mix affect strength?
does pool water used to make a concret mix affect strength?
(OP)
hi. I am from a construction company. We had a situation where the municipality shut the water supply whilst in the midst of mixing concrete on site. we use a mechanical mixer and it is for a floor slab. NHBRC states that the min strength for a floor based slab is 10mpa. We are mixing a 25 mpa strength.
To complete a section we backwashed aprox 40l water from the clients pool and used it for one mix out of a 300 sq metre slab. When i informed the project manager of what we had done, he is concerned that the chlorine in the pool water might destaibilise the concrete. It is unreinforced concrete, with a mesh inlaid.
Can somebody please advise me wheter this is correct?
To complete a section we backwashed aprox 40l water from the clients pool and used it for one mix out of a 300 sq metre slab. When i informed the project manager of what we had done, he is concerned that the chlorine in the pool water might destaibilise the concrete. It is unreinforced concrete, with a mesh inlaid.
Can somebody please advise me wheter this is correct?






RE: does pool water used to make a concret mix affect strength?
RE: does pool water used to make a concret mix affect strength?
Provided you kept all other parameters the same, strength will not be affected.
The chlorine will not "destabilize" the concrete. The only effect you get from higher chlorine (chloride) is a higher potential for rebar corrosion, which doesn't apply in your case. Don't worry about the mesh...it's probably not doing any good anyway!
RE: does pool water used to make a concret mix affect strength?
I would second the concern over the higher potential for rusting of your mesh. If the mesh is on the ground - bottom of the slab - where it usually ends up - then no problem. If you chair it high you possibly could get some minor spalling.
RE: does pool water used to make a concret mix affect strength?
There are days when I wake up feeling like the dumbest man on the planet, then there are days when I confirm it.
RE: does pool water used to make a concret mix affect strength?
RE: does pool water used to make a concret mix affect strength?
You never know what is in a pool.
Probably O.K., but it makes the contractor think twice, even in a crisis situation.
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
RE: does pool water used to make a concret mix affect strength?
Seriously, your dilution - at "40l water from the clients pool and used it for one mix out of a 300 sq metre slab - is pretty high.
RE: does pool water used to make a concret mix affect strength?
I'll assume this is a joke.
RE: does pool water used to make a concret mix affect strength?
wow ! who would have thought it would be this easy to get technical advise
But seriously , I really thank you guys who take your time to answer and assist in finding solutions on this site.
AND yes i would drink from this pool-sparkling blue water and NOOOO no one was buried in the concrete