Puerto Rico Shootcrete Nightmare

[Neto]

Its been one thing after the other for me, my pool was shotcrete last friday and the crew had a lot of issues. This pool is a geometrical style and has about 12' x 28' with an infinity spa, etc, etc.. I got quoted 28 yards to complete this job and they divided 3 trucks with 10 yards on 1st, 2nd and 8 on third. The problem started with the second truck that had 10 yards of concrete, it arrived at my house 1 hour after leaving the plant... Two pipes of the pump broke at different times and finally the pump broke down. The crew had to get another pump and that took about 45-60 minutes. They told me that the company had to put a retarding additive to the mix (still about 6-7 yards left on the truck) to be able to conserve the concrete while the second pump arrives. So the second pump arrives and they start pumping this concrete, I was told by the crew building my pool that the concrete was very warm but no one said that it was bad. The second pump, most of the lines got blocked after pumping 2-3 yards, the concrete was not suitable for pumping anymore. So the second truck left with about 5 yards of bad concrete and the pumping crew started to unclog the lines. The 3rd truck with 8 yards came about 4 hours after the second arrived and everything on the pool was pretty much dried before they started pumping again. This is what I ended up with:

 

[Neto]

second round of pictures

 

[Neto]

Now I have already mention my concerns with this job and I have let know the subcontracting company about it. I will be calling in tomorrow to ask for a full refund on this job but the big question is, what am I facing here? Do I have risk of this pool cracking down years to come? Is it suitable to continue the project? or does it have to be teared down?

thanks

 

[kimkats]

My guts says it all needs to be jack hammered out and started over I AM going to call in a couple of people who are experienced pool builders. @bdavis466 @jimmythegreek

 

[Neto]

My guts says it all needs to be jack hammered out and started over I AM going to call in a couple of people who are experienced pool builders. @bdavis466 @jimmythegreek

i really hope not ☹, thanks for responding

 

[jimmythegreek]

Hard to say by looking at it. The only way to know is to have a concrete analysis done on the problem spots amd see what it reveals. The biggest issue you have is with the time between loads. If the material wasnt applied correctly with the proper slump its considered rebound and it will eventually deteriorate. With normal concrete pours material is much more forgiving but shotcrete and gunite require specific application techniques amd material open window time. If multiple sections are poor quality it would then unfortunately be a total rip out to be on the safe side. I'm sorry this happened to you

 

[Neto]

how should i do the analysis? im guessing we need to drill some samples and sent somewhere? Was this gunite or shotcrete?

 

[Neto]

Hard to say by looking at it. The only way to know is to have a concrete analysis done on the problem spots amd see what it reveals. The biggest issue you have is with the time between loads. If the material wasnt applied correctly with the proper slump its considered rebound and it will eventually deteriorate. With normal concrete pours material is much more forgiving but shotcrete and gunite require specific application techniques amd material open window time. If multiple sections are poor quality it would then unfortunately be a total rip out to be on the safe side. I'm sorry this happened to you

 

[jimmythegreek]

That's shotcrete the mix is in the truck ready to go they use pneumatic pressure to apply. Gunite is mixed at the nozzle with water. The tow behind compressor is what gives me my basis. As for what to do an engineer who knows pools would have to evaluate. It's impossible for me to look at pics and give you honest info or a recommendation. Keep in mind no contractor wants to eat a job so they will all tell you its ok unless they are honest business people amd give it to you straight......good or bad

 

[Neto]

That's shotcrete the mix is in the truck ready to go they use pneumatic pressure to apply. Gunite is mixed at the nozzle with water. The tow behind compressor is what gives me my basis. As for what to do an engineer who knows pools would have to evaluate. It's impossible for me to look at pics and give you honest info or a recommendation. Keep in mind no contractor wants to eat a job so they will all tell you its ok unless they are honest business people amd give it to you straight......good or bad

thanks for the info and suggestions. I have had people over that work directly with supply of comcrete dispatch companies and have told me that the quality of the concrete seems to be good and solid. A structural engineer did saw some pictures i sent over and what he said was that i should basically break what appears to be some cold joints and apply a strong epoxy just to be sure but if it had good rebar then it will be ok. I did research shotcrete cold joints and the first thing i found was an article that mentions that there is no such thing as a shotcrete cold joint or at least the American Comcrete Institutes dont recognize shotcrete cold joints, here is the article: https://shotcrete.org/wp-content/uploads/2020/01/2014Spr_TechnicalTip.pdf
here is the conclusion of the article:

"shotcrete placed in layers does not produce a “cold joint” as defined by ACI, because it produces excellent bond between the layers. This has been confirmed by visual inspection of numerous cores taken through multiple layers of shotcrete, where it is often impossible to identify where one layer stops and the other starts, unlike cold joints in cast-in- place work where the difference between lifts is readily apparent."

 

[jimmythegreek]

That is true to an extent. The pressure applied does a great job of packing the shotcrete tight into the material its joining. The caveat to that is mix quality. My concern would be areas where the mix slumped up and was too stiff to shoot, amd any areas (if any) where the material was overworked and added by hand. With shotcrete you overshoot a little amd shape by removing material like sculpting a statue.
I would spend the money amd have the engineer come out. Its not that expensive in the grand scheme of things to be sure its sound. See if the sub and PB will share in some of the expense of it

 

[RoyR]

Does not produce cold joints if it was properly prepared...this does not sound like that, cold joints will cause cracks in the plaster and pool leaks. I’d rip it all out and start over.

 

[Neto]

Does not produce cold joints if it was properly prepared...this does not sound like that, cold joints will cause cracks in the plaster and pool leaks. I’d rip it all out and start over.

thanks for your suggestion, what do you consider a proper preparation?

 

[jimmythegreek]

Like I said earlier, internet info is no substitute for being there. The concrete has an open window time when first poured a few hours is ok depending on what was going on with temps, the mix, etc. None of us can give you sound advice amd you shouldnt take it at this point. This is major have a licensed engineer that knows pools amd shotcrete evaluate it then you know where you stand. Hes independent and doeant care who is responsible for what and why