Shotcrete pool built without radius where pool walls meet floor

[jzg135]

I've been in the midst of decent sized project involving an inground shotcrete pool and surrounding patio/landscaping for the last 6 months. We dealt with a nightmare pool builder who constantly missed deadlines, went AWOL for weeks at a time, and finally we found out he ran out of money and we were able to terminate him and bring in a new pool builder to finish the job.

Our new pool builder is concerned because the walls on the pool where they meet the floor are all at 90 degree angles (see photos attached), and have no radius built into them. The engineered drawings showed a 6" radius in the shallow end and a 9" radius in the deep end. The pool is 18'x46' rectangle with an 8' tanning shelf and depth goes from 3'6" to 6'6".

As far as I could tell, the construction of the pool was done well and there was plenty of rebar. But the other concern the new pool builder has is that they shot the pool in 2 days, first they did the bottom and then they shot the walls. So there is a cold joint at the base of the walls, although I've read with shotcrete that a cold joint should not be an issue.

Should I be concerned with that sharp of an angle on the walls? Can we add in a radius to solve this or are we facing a massive fix (i.e. chipping out walls and reinforcing back into the existing rebar, etc)?

 

[jzg135]

And here are some photos of the rebar, prior to pool being shot and one photo after day 1 of shotcrete.

 

[JJOM]

I am not expert, but I have watched some YouTube pool build that had sharper transitions like yours. Maybe they are using a different surface/finish?

Here is one video where they build ICF pools and they seem to have this:

eta: I am far from an expert, and just wanted to show similar looking jobs. I really have no idea and wish you the best in getting this done correctly.

 

[Jaffles]

No expert either and sorry to hear of the experience. I tend to feel the curved edge is more for athletics and feel from within the pool, opposed to a structural benefit. The reo is spaced well and I presume tied. Might just be how one PB does it to another. For instance my reo shell has no roll over on the top. It just comes straight up. I think they all look for ways to be more efficient and save costs, but that doesn't not mean its wrong because its different to how its always done because Dad dit it this way. But not guarantee either.

I'm having my straits raised, they are adding a "slurry" of the particular type of gunite used in my pool. No doweling just slutty. One step by 1" and the second is 2". They tell me it will last and no ill effect, just they need to use the same mix as a slurry.

Interestingly when it was getting sprayed, I asked for the top step to be larger. The gunite had started to set and ol mate gouged some grip into its vertical face, then started to add it via trawling. Well it just fell off and would not stick. Thankfully the gunite owner was there and he gouged it a lot more and was really quite aggressing with it. He then got the gun and started spraying it on which it stuck no problems.

Not an answer to your pool unfortunately, but hope it helps in some way. Maybe chat with the gunite applicator to get his thoughts?

 

[Charlie Bezzina]

Square corners is actually a thing. pb told me they are considered a "high end" feature for modern pools. People pay extra for that.

 

[AQUA~HOLICS]

No reason to be concerned, very common in commercial pools in my area, photos appear to show proper rebar placement.
You can add a radius with more Shotcrete, if you go over 6” I would add rebar.
Plaster can be applied to also give a radius up to 3” depending on type and application crews experience.

 

[jzg135]

No reason to be concerned, very common in commercial pools in my area, photos appear to show proper rebar placement.
You can add a radius with more Shotcrete, if you go over 6” I would add rebar.
Plaster can be applied to also give a radius up to 3” depending on type and application crews experience.

Thanks, our new pool builder mentioned possibly using gunite to add the radius (he specifically works with gunite, not shotcrete). Would it matter if it was gunite or would you recommend shotcrete for adding to the radius?

What would be your suggestion for adding the rebar if it was over 6" radius? Trying to visualize how that would be done but not quite sure the best way to do it and would appreciate your insight. Thanks!

 

[AQUA~HOLICS]

My personal experience, I advise to use Shotcrete on my jobs for the main reason that the mix ratio is done at a concrete yard by a computer. Gunite is mixed at the job site and can have the water ratio adjusted at the nozzle. This can be a bad thing if too much water is added to buy time for the finishers.

For adding rebar to an existing shell it would need to be core drilled to accept the proper size rebar and a epoxy used to hold in place. This exact situation is common on remodeled pools. A steel engineering plan would be used to follow for size and location. I will provide a picture of the epoxy that is required in my area.

 

[jzg135]

My personal experience, I advise to use Shotcrete on my jobs for the main reason that the mix ratio is done at a concrete yard by a computer. Gunite is mixed at the job site and can have the water ratio adjusted at the nozzle. This can be a bad thing if too much water is added to buy time for the finishers.

For adding rebar to an existing shell it would need to be core drilled to accept the proper size rebar and a epoxy used to hold in place. This exact situation is common on remodeled pools. A steel engineering plan would be used to follow for size and location. I will provide a picture of the epoxy that is required in my area.

Ok great thank you for the info, makes me feel a lot better. The new PB is suggesting bringing in an engineer and having him do a site survey and then analysis on how to properly add the radius but I think its a waste of money and he can easily add the radius himself without going through the whole process of the engineer.

 

[jzg135]

Ok great thank you for the info, makes me feel a lot better. The new PB is suggesting bringing in an engineer and having him do a site survey and then analysis on how to properly add the radius but I think its a waste of money and he can easily add the radius himself without going through the whole process of the engineer.

My personal experience, I advise to use Shotcrete on my jobs for the main reason that the mix ratio is done at a concrete yard by a computer. Gunite is mixed at the job site and can have the water ratio adjusted at the nozzle. This can be a bad thing if too much water is added to buy time for the finishers.

For adding rebar to an existing shell it would need to be core drilled to accept the proper size rebar and a epoxy used to hold in place. This exact situation is common on remodeled pools. A steel engineering plan would be used to follow for size and location. I will provide a picture of the epoxy that is required in my area.

Also we are leaning towards Pebblesheen for the plaster. Is that something that has the strength to add the radius up to 3"?

 

[AQUA~HOLICS]

3” is the maximum depth I would go on plaster and that’s only because my applicator has done this before and I have seen the process.

 

[jzg135]

Great thanks again for all the replies. @AQUA~HOLICS in your opinion do I even need to add the radius? We're at a point where we can't throw any more money away, especially if its not needed so I would love to hear your thoughts.

What would be the concern if the radius isn't there and I plastered the pool? I'm trying to wrap my head around worst case scenario but to me it seems as if there's not much that could happen with the way they built the pool.

 

[AQUA~HOLICS]

On the jobs I’m involved with, all of them residential pools, they can be a rectangle on the top 18” and then the Shotcrete crew will start to radius out the corners as they go downward solely for the purpose of creating a bowl for the pool sweep to operate in and to help with circulation of the water to move the chemicals to all areas of the pool.
The pool being at the point it is at now it’s probably best to keep it as is and see how much if any adjustments you will need to do once it’s filled . I’m thinking not many other than the two I mentioned.