The Effect of Rice Husk Ash Addition on the Compressive Strength of Fly Ash-Based Geopolymer Concrete

The increasing demand for concrete has led to a surge in cement production. However, it is essential to note that this process releases significant amounts of CO2 into the atmosphere, which has a detrimental impact on the environment. Rice husk ash and fly ash have the potential to replace Portland cement as they are pozzolanic materials, containing silica (Si) and alumina (Al). The objective of this research was to determine the compressive strength of fly ash-based geopolymer concrete with the addition of 10-30% rice husk ash at the age of 7 and 28 days. The results indicated that the addition of rice husk ash reduced the compressive strength of the geopolymer concrete, regardless of whether the specimens were cured at room temperature or in an oven. This reduction in compressive strength became more significant as the percentage of rice husk ash replacing fly ash increased.