Fixing Driveway Cracks
Repairing small cracks in your concrete driveway, those up to a 1/4 inch wide, can be done with a shop-vac and some silicone sealant. The crack in your concrete driveway should be cleaned using a small brush or broom to remove the larger material, and then the shop vac should be used to remove any dust and smaller debris. Then inject the silicone calking into the driveway crack and use your finger and some paint thinner to give it a smooth and finished look.
To repair bigger cracks in a cement driveway, grab a concrete repair kit from Ace Hardware or Sears, or order one online from Amazon.com or Buy.com. To fix the cracks in your cement, you're going to need a buck and trowel, as well as a shop-vac, and a hand-held grinder to use to 'chase' the crack with.
Make sure any large pieces of cement and gravel are removed from around the crack on the driveway before using the grinding wheel. Then follow the crack with your handheld grinding wheel, grinding the crack to a depth of 1/2 to 3/4 inches along its entire length. Use the shop-vac to remove all the concrete dust and debris from the work area when you've finished grinding.
Fill the crack with the primer that came with your concrete crack repair kit. Some repair kits only use a single product that also acts as the primer. In this case use it as shown in the directions on the package, or follow the primer directions above. Before the primed area dries out, sprinkle a fine layer of masonry sand over it and then let it sit until it's dry.
When the primer is dry, you can fill the crack with the main crack filler that came with your concrete repair kit. When the is full and while it's still wet, fill the crack to the top with sand. Use a trowel to smooth out and remove any of the extra masonry sand and cement repair compound. Use the damp sand mixture to fill any holes or cracks that where missed, or aren't completely full. Once the repaired concrete has dried sufficiently, use a grinding wheel to blend the surfaces for a visually appealing finished product.