The cure time for a concrete driveway is about 28 days under optimal warm-weather conditions. This length of time should cure the concrete sufficiently to a hardness of 4,000 psi, though suboptimal weather conditions prevent this.
During warm-weather conditions, a driveway is often covered with a cure-and-seal liquid membrane that aids hydration of the concrete without allowing it to dry out. The membrane is placed onto the concrete in a thin layer shortly after the concrete is poured. The poured concrete is allowed to dry just enough to allow the placement of the membrane without damaging the surface before the membrane is either sprayed or rolled into place. Manufacturers of cure-and-seal membrane provide precise instructions on the most effective thickness of the membrane.
Newly placed concrete for driveways should be poured when there is enough anticipated warm weather to allow for two months of temperatures above 40 degrees Fahrenheit to let it cure and dry. The first 30 days are for curing, with the second month of warm weather required to dry the concrete out. If two months of sufficiently high temperatures are unlikely, then cold-curing methods must be used to get the concrete driveway to dry to sufficient hardness.