[titan7]

Poured 2100 SF 24 days ago. Started noticing hairline cracks, near the skimmer and a a couple in other places. They put 5" of compacted CAB road fill down, rebar 24"on center, the slab is 4-5" thick, 3500 psi concrete. They said they pump at a 6 slump. Could find nobody that would do a 5 slump.

The control joints were tooled in at 8ft, basically 8ft squares. There are hairline cracks in many of the control joints, but it seems the concrete had other thoughts. So is this just life with concrete? Not sure what else I could have done here. It's been almost 4 weeks, and most of it is still pretty dark grey and blochy. There are also some spots that I don't think we're finished that well but I may just be too picky. They did leave a 8x7 slab that is pooling 1/4" of water, they agreed to demo and repour that piece, I assume since it against a new wall they can demo it without damaging the slab it's connected too and the wall? So how do they deal with the fact the rebar in the repour will not be connected to the piece next to it?

Sorry for all the questions but I still need to pour another 1000 ft in the front. I would like to avoid similar issues.

Thank you

 

[stadry]

1st guess is an insufficient jnt pattern OR improperly installed jnts ( time / place ),,, when they demo, leave the rebar in place - your slabs will still be connected altho i can't imagine why you'd want that,,, impo, ixnay on rebar across a joint held by conc on both sides,,, both liquids AND solids change dimensions due to changes in temperature ( hy skoul fizix, remember ? )

 

[titan7]

insufficient joints? That would really suck, since you hire to professional to know this stuff. The control joints were tooled in same time as the pour (well once it set up a bit). Very frustrating as a home owner to deal with this, you are at the mercy of the contractor and just have to trust they do it correctly.

So I am assuming that I should repair these small hairline cracks they are about 1/32" wide or a lot less.

 

[bob22]

I may be wrong but I think the rebar needs to be part of the pool bonding system. If they replace existing you will want to make sure that is done properly.

 

[Tscarborough]

What does this have to do with DIY?

 

[titan7]

I am debating re-doing it myself if this should not have occurred, why pay a pro to screw it up when I can screw it up for free if there is a mistake.

 

[stadry]

ok, i'll bite - what is a ' pool bonding system ' ???

 

[bob22]

All the metal parts, the ladder, pump, light, etc... (and I believe now includes the water in the pool) need to be connected together so all are at an equal electric potential (not grounded per se). It is a complicated code and best left to a pro; not having it done or done properly risks electric shock.
One thing I found fast showing all bits involved:
http://www.harger.com/library/LineCards/Pool%20Grounding%20Bonding%20Line%20Card.pdf

 

[stadry]

conc pool aprons/decking aren't part of the pool & are separated by expansion joint material ( or should be ), no ?

in any event, no steel should be attached into both slabs across a joint,,, grease 1 side so it can slide/move as conc expands/contracts

 

[bob22]

The connection to the rebar and rest of metal bits are with wire; the connection isn't structural, just electrical.
The problem if decking isn't included in bonding: say motor has ground fault, energizes pool ladder, wet feet on deck grounds person when they touch ladder and they get a shock if it isn't at same electrical potential as ladder etc...Hard for me to explain properly but my family is worth protecting to do it.