Should I be worried about wavy control joints on a new slab?

Wavy control joints won't hurt the structural integrity of the slab at all. Those joints are just pre-planned weak spots to encourage the concrete to crack in a straight line instead of randomly across the surface. Even if the tool struggled to push the aggregate aside, you likely still created a deep enough point of weakness to do the job. Since a shed is going on top, the framing will hide most of those edges anyway, so the aesthetics are a non-issue. Wating too long to finish is a classic mistake when you're working without a full crew. If you ever run into that again where the slab is getting too hard to tool, you can acutally wait until the next morning and use a **circular saw with a diamond masonry blade** to cut the joints. It creates a much cleaner, professional-looking line than trying to force a hand groover through setting concrete. Just make sure you cut about one-quarter of the slab's depth to ensure the crack follows the saw line.

Regarding those shallow puddles, they're mostly a nuisance rather than a failure. On a shed slab, water ponding usually means the slab isn't perfectly dead-level, but if the building has a proper roof and overhangs, that concrete should stay dry most of the time. Just keep an eye on where the water sits in relation to your bottom plates. When you install the shed, use a high-quality **sill sealer** or a pressure-treated bottom plate to prevent that standing moisture from wicking into your wall studs. Get those forms pulled as soon as you can so you can get your tractor out. Leaving them on too long won't hurt the concrete, but the wood can sometimes bond to the edges or warp, making them a pain to pry off later. Since the concrete has already set up enough to support its own weight, you're in the clear to clear to clear to strip them whenever you have an hour of daylight.

Have you ruled out the possibility that forcing that tool thru the stiff aggregate created micro-fractures you can't see yet? It might be fine for a light shed, but if you’re planning on driving that work tractor over it, those weak spots coud become an issue later.

Also, regarding the puddles—have you ruled out sub-base settlement? If the gravel wasn't packed tight, those shallow spots might get deeper once the slab is under a real load. I'd be a bit worried about the ground being truly stable if it's allready holding water like that.

Honestly, don't sweat the puddles too much. I had the same issue on my backyard workshop slab becasue I got sloppy with the screed. I just took a 4-inch angle grinder with a masonry cup wheel and ground down the high spots around the birdbaths. It took about twenty minutes and now the water drains right off. Since you've still got your tractor there, check if you can use the bucket to scrape away some of the dirt from the slab edge once you yank those forms. If the water has nowhere to go, it'll just sit there regardless of how level your finish is.

Forget the wavy lines, they're just character. My concern is the tractor weight. If that's a 4,000-lb machine and you only poured a standard 4-inch slab with 3000 PSI mix, those edges are gonna be your weak point once you pull the 2x4 forms. I'd definatly hit the surface with a lithium densifier like Ghostshield 8510 to help with the dusting in those low spots. Since you're busy, just make sure you don't park that tractor on the green concrete for at least 14 days or you'll see real structural cracks, not just wavy tool marks.

Back in the 70s, we didn't have fancy diamond blades on every truck. If we missed the window for a groover, we'd just let it go and hope for the best. Those wavy joints aren't pretty, but they'll hold. My real concern is you leaving those forms on while the concrete's still green and then driving a tractor over it. I’ve seen guys snap the green edges right off a fresh pour becasue the forms were still pinned tight. Pop those boards off before you bring the heavy iron trough. If you're worried about those puddles, just keep a bag of Portland handy and dust the low spots next time it's wet—old school way to soak it up, though a shed doesn't need to be a masterpiece.