Q.: Curling is a big problem in our part of the country and we are concerned about ways to prevent it. Would thickened edges of the slab reduce or prevent curling, and if so, how much would they have to be thickened?

A.: Thickened edges would reduce or prevent curling, but because they provide additional subgrade restraint they could readily cause cracking elsewhere in the slab. It doesn't seem like a trouble-free solution.