Raised Sport Court Slab

[Blooongeey]

It is proposed to utilize a concrete lid over a residential basement, approximately 20’x40’, which can be used as a sport/pickle ball court. I do not have any guidelines for this type of application. My question here relates to adequate stiffness to accommodate the activities above.

Thank you in advance,

Michel Blangy, PE
Redondo Beach, CA

 

[jayrod12]

Ignoring the capacity of the residential basement walls and the foundation that supports them, you're going to need a mighty stiff slab for it to maintain the levelness expected long term for something like that. You've essentially got a pin connected simple span slab, and long term creep will be an issue, so I'd be betting you're in the range of 14-16" thick. And you may want to have the contractor build some camber into the formwork so that once the dead load of the slab is required to be supported by the slab only (after formwork removal) the final surface is near level.

You're also talking about almost 3000 lbs/ft of vertical load applied to the top of the foundation wall. It's not nothing and you'll want to ensure that all works out.

Often people get these ideas that it's cheaper to re-use some existing elements, when often it is not. This may be one of those cases where it is not.

 

[XR250]

Can it be on composite decking over steel beams?

 

[SJBombero]

Depending on where this large flat spot occurs on the property, the fire department may want you to design it to support their trucks.

Trying to solve this with conventional rebar is a losing battle. Prestress panels or a post-tensioned slab are much more efficient.

 

[TLHS]

Can you install intermediate walls in the basement, or do any walls already exist in the basement?

 

[hokie66]

A regulation pickleball court is 20'x44', but you need some space at the ends and sides. Are these surrounds to be concrete as well?

I see no reason why conventionally reinforced concrete would not work. Perhaps a column with drop panel below central to the court?

 

[Blooongeey]

Replying to responses provided thus far:

Composite decking and steel might be feasible, however I still question the stiffness of such an assembly.

As the space below is a large theatre/recreation area, there is no option for intermediate walls, or posts.

There is minimal 4’ setback sideyard space available around the slab.

Thanks all. Still pondering .. I believe the architect is going to want to go with the brute force method/poured in place concrete approach so as to keep it simple.

I am looking into the post tensioned option though.

Thanks all.

 

[phamENG]

Stiffness should be easy enough calculate. Beyond some basic deflection characteristics, I'd look into vibration characteristics as well. That's likely to be your limiting factor with 4 people moving quickly and randomly around. It'll be the single footfalls with 200lbs behind them as somebody jumps that will define your serviceability limits.

 

[XR250]

For my edification, would vibration even be an issue if it was designed for normal 40 PSF live load (32k) serviceability?
I mean (4) 200lb people randomly jumping with that much structure mass does not seem like it could be an issue.

 

[JLNJ]

We used a hollowcore-with-heavy-topping system for a basketball court recently. It’s been built for a couple of years and I haven’t heard any complaints. Our span was a little longer so we had a close look at vibrations and personnel comfort. Worst case would be some sort of exercise or dance where everybody jumps up and down together.

Ours was elevated and inside so we didn’t need to worry about vehicle loading.

 

[EdStainless]

The problem is exactly what JLNJ brings up, not the original Pickle Ball games but 40 people in a dance exercise class.
The other catch with outdoor courts is that they can't be perfectly flat or water will pool, so you need a tiny bit of slope but not enough to bother the players.

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P.E. Metallurgy, consulting work welcomed

 

[phamENG]

If it's going to be a massive 16" thick concrete slab, no - no vibration issue. But a composite steel design was brought up and the OP questioned the stiffness. If you thin it down to a series of W12's with a composite form deck and only 3 or 4 inches of concrete...I could see it getting a little bouncy.

 

[Blooongeey]

Any further info/details/spec's. on this? I am thinking this is something I can talk to them directly about to have fabricated, then installed.

 

[Blooongeey]

This is mostly what I am looking for a reference for, as to how I can quantify.