The following figure from the above paper shows Trends (in degrees Celsius per 100 years) for each 5 by 5 latitude-longitude grid box using only nonurban stations for annual maximum temperature, annual minimum temperature, and diurnal temperature range for the period 1950 to 1993.
Concrete continues to gain strength after pouring for as long as it retains moisture, but the longer it moist-cures, the slower the rate of strength gain. Moist-curing concrete for 20 days more than doubles its strength compared with four days of moist-curing, which is considered a minimum.oncrete continues to gain strength after pouring for as long as it retains moisture, but the longer it moist-cures, the slower the rate of strength gain. Moist-curing concrete for 20 days more than doubles its strength compared with four days of moist-curing, which is considered a minimum.
Voted Best Answer. I agree with Ben, as usual. First, test your slab - put a sheet of plastic over it, at least 3 feet square, taped down to the slab all around - leave for 3 days. If the slab darkens with moisture, or there is any condensation drops on the underside of the plastic, you have a damp slab.