Performance of Rice Husk Ash Concrete in Sulfate Solutions

Durability of concrete is defined as its ability to resist deterioration after exposure to the environment of its use. This work examined the performance of Rice Husk Ash (RHA) concrete in sodium sulfate (Na2SO4), magnesium sulfate (MgSO4) and combined Na2SO4 and MgSO4 solutions. Concrete bar specimens and cubes were prepared for elongation and strength deterioration tests respectively using RHA replacement at the 7.5% replacement by volume, which had achieved the highest compressive strength from a previous study, as well as at the 30% replacement by volume, which was the highest replacement for the study. Strength deterioration tests were performed on the 7.5% replacement by the weight of cement. From the elongation findings, it was concluded that at the 7.5% replacement, RHA could be used with an advantage over 100% cement concrete in MgSO4 environments, whereas at the 30% replacement, RHA could be used with an advantage over 100% cement concrete in both the Na2SO4 and mixed sulfate environments. For strength deterioration, the findings show that RHA could be used in both the Na2SO4 and mixed sulfate environments with an advantage over the 100% cement. RHA was also found to be more effective in resisting surface deterioration in all the sulfate solutions.