Effect of Water Proof Admixture on Hardened Concrete

Abstract

Admixtures improve the compressive strength of concrete. This study shows the using of water proof admixture on hardened concrete (40MPa) when the samples Water curing condition is used and the age at testing are 7, 28 and 90 days to evaluate the mechanical properties such as compressive strength, splitting tensile strength and flexure strength and 28 days and are exposed to temperature (100°C and 500°C) at samples in 28 days. In this study the compressive strength decreases by about (33.03 %) and increases by about (29.95%) at (7 and 90) days respectively. They study shows that the compressive strength decreases by about (0.96% and 19.12 %) at 100°C and 500°C respectively while  the tensile strength decreases by about (2.06% and 19.38%)  at 100°C and 500°C respectively, and  the flexural strength decreases by about (3.01% and 21.07%) at 100°C and 500°C respectively. All the above results are compared with cubes tested at room temperature (25 °C).