RELATIVE HUMIDITY ON THE CORROSION IN REINFORCED CONCRETE STRUCTURES 

Moisture profiles in drying concrete were first tested by using specially manufactured prisms (100 x 100 x 150 mm) with cavities for humidity measurements. Six prisms were cast using 100 % CEM I 52.5N cement, at two different w/b ratios (0.45 and 0.65). Four of the prisms were subjected to 14 days wet curing in water at 35°C, whereas the other two cubes were placed in a room with controlled conditions for dry curing (Humidity of 50 ± 5 %, with a temperature of 20 ± 2°C). Once cured, cavity plugs were put in place and the specimens were prepared by applying epoxy to five of the six surfaces. Tests were then carried out by subjecting the prisms to two different environmental situations. The first being a dry hot climate, imitated by rapid drying in the oven at 50 ± 2°C, with the second being a moist warmer climate, imitated by using a controlled environmental room (Humidity of 50 ± 5 %, with a temperature of 20 ± 2°C). Moisture measurements were then taken, by using a small humidity probe, every 24 to 48 hours.