Concrete slabs should be level on the surface, but sometimes they end up being rough or uneven for several reasons. These slabs should be leveled so that people walking over them don't trip, and so that any carts being wheeled over them don't wobble and fall. If the concrete lines a driveway, you don't want to damage the shock absorbers by making vehicles drive over a very bumpy surface. You need to make that concrete surface more level, and there are a couple of ways you can go about it.
One option is to saw through the slabs of concrete and remove the uneven sections, filling in the space with a new slab that is level. The other option is to grind the surface of the slab to even it out without removing anything else. Concrete cutting companies often offer both options.
How Prominent Is the Uneven Surface?
The prominence of the uneven surface is one consideration. An annoyingly but mildly rough surface may benefit from grinding as it wouldn't take that long to do. Even a very noticeable lump that wasn't that big in terms of diameter could be ground down. However, if the unevenness is very noticeable and tall, (as if someone had taken a sledgehammer to the surface of the concrete and left divots all over the place), then sawing through the slab and replacing it is best.
How Large Is the Uneven Area?
Another consideration is the uneven area. A very large uneven area may benefit from replacement as grinding might take too long. Again, the severity of the unevenness will play a role in this decision. But the larger the area, the more likely it is that the concrete should just be replaced.
How Thick Is the Slab?
Slab sawing uses relatively large blades and that can cut through some thick concrete. If the slabs are within the cutting range of the blades, you can saw through and replace them. If they're too thick, you will likely have to resort to grinding and resurfacing, although it could be possible for the sawing company to special-order larger blades. But if not, grinding is the only real option.
Level concrete is much safer than bumpy, torn-up concrete, and while some roughness can be beneficial—such as grooves and raised strips that slow traffic and increase traction—most of the time, smooth, level concrete is the best. Speak with a concrete slab cutting service to figure out which will be best for your situation.