Walk on it after 24 to 48 hours, drive cars on it after about 7 days, and keep heavy trucks off for the full 28-day cure. Concrete reaches roughly 70 percent of its design strength in the first week and its rated strength at 28 days.
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Concrete does not dry; it cures, a chemical reaction that needs time and moisture. The strength curve is steep early and long afterward: roughly 70 percent of design strength arrives in about 7 days, and the 3,000 to 4,000 psi the mix is rated for is a 28-day number. The practical schedule follows that curve. Foot traffic is fine at 24 to 48 hours. Passenger vehicles wait about 7 days. Concrete trucks, moving vans, loaded trailers, and equipment wait the full 28, and on a rural drive it is worth scheduling deliveries around that window. Cure quality is set in the first week, which is why the scope states the method: curing compound sprayed at finish, or wet curing, either of which slows moisture loss so the surface gains hardness instead of dusting. Texas summer makes this real: a slab poured at 100 degrees and left bare can lose water faster than the reaction can use it, which is why summer pours start at first light and cure protection is not optional. Two first-year rules protect the investment: keep deicing salts off the slab its first winter (the surface is still maturing and salt scaling is permanent), and keep skid-steer turns and trailer jack points off the edges. After that, a correctly built slab does not ask for much for a very long time.