Polyethylene film as concrete curing material in a tropical climate

Abstract

Concrete specimens were cast at and exposed to three different climatic regions in Ethiopia. The specimens were cured for different length of time, either covered with transparent polyethylene film, or by intermittent watering. At the end of the curing periods the specimens were stored at 20°C and 65% relative humidity until tested for compressive strength. Reference specimens were cast at 20°C and water cured, after 24 hours, for the next 6 days and finally stored at 20°C and 65% relative humidity. After 24 hours, the compressive strength of specimens exposed to the different climatic regions ranged from a high of 322% to a low of 77% of reference specimens, depending on the environmental conditions and type of curing media used. At higher ages, no deficiencies were observed from specimens cast at and exposed covered with polyethylene film. Others showed pronounced deficiencies.