Concrete driveway question

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No expansion joints?

Typically, the first cracks you see are from shrinkage and drying. You should have expansion joints that minimizes these cracks and controls the crack locations

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Not being an engineer ...

I assume the cracks are forming at expansion joints, yes. I know the guy put metal dividers every so often, which seemed to disappear in the final product (I knew where they were, but didn't see them). That's where I am now seeing these cracks. The cracks are uniform, parallel, and appear very straight.

Driveway is basically a long rectangle, which at points expands to meet a two car carport (which wasn't pulled up). Carport WAS about 4 inches higher than the driveway, the driveway sloped downwards TOWARDS that before.

New driveway starts at that elevation, stays flat with a slight grade, out towards the road. This resulted in some THICK concrete near the house, as I would say the part at the road is still at least 4-5 inches thick at minimum.

The cracks I see are all linear, and would be blocks. It's as if you laid it out as blocks... one side of the driveway has rectangles from the carport to the road. At each time there is an angular change, to create the expansion in width, there is a crack, seperating it from the block.

So, there is a series of rectangles, with a 30 degree Right Triangle alongside it, and then one with a different angle (lesser angle so it comes into the carport...that isn't divided off at that angle, but instead is a 4-sided polygon aside a square).

The cracks all appear to be at 90 degree angles from each other, either parallel or perpendictular, and straight. Nothing wandering, or skewed. I see them, but it's not like I can place anything inside them. It's just not a flush, singular surface anymore.

That's correct to what it should be, right?

Thanks, and meant no harm with the engineer comment. Just outside my field of expertise

I’ve heard concrete wants to crack every 10 feet. Never understood why they make control joints at 20 feet

Because you measure from the middle of the section. Middle to each side should be 10' to either an expansion joint or and edge.

Control joints should be set no more than 2 1/2 x thickness of concrete with a max of 15’. 4” thick concrete would put joints at 10’ each way. Sidewalk joints should be set 5’ on center. If your contractor is not doing this, the likelihood of having additional cracking does go up significantly.