If you remove approx 1 inch of concrete to patch a crack, is it necessary to cut thru the slab of concrete?

Question

I'm trying to patch several large cracks in my concrete driveway, I've rented a concrete saw which works pretty great (power tools rock!), for cutting concrete. Anyway I've cut about 3/4" into the concrete and was wondering if that is deep enough to put a solid patch. Please help!

Answer 1

When patching concrete it is most important to excavate a wider region below the surface than the opened crack. That is, the shape of the patch will be wider inside the crack than outside.You might do this with a chisel or hand grinder.

The reason for this is to prevent the concrete patch from popping out when it cures and to lock it in place even when it freezes.

Answer 2

no it isn't, but be warned it will crack there again. you should use a bonding agent to make your patch adhere to the old concrete.

Answer 3

i would go deeper, 2 in. or more and wide enough to under cut the bottom of the trench...