Influence of rice husk ash on compressive strength of an aerated concrete

Abstract

The world is becoming increasingly concrete-filled; the world is engulfed in pollution and the depletion of naturally available materials, resulting in global warming. So, using eco-friendly materials is the best supplement to replace or add with the concrete to enhance the properties, and usage of these kinds of concrete blocks is most needed. Aerated blocks usage helps in decreasing material usage compared to conventional concrete. Aerated concrete blocks are lightweight blocks with eco-friendly nature and act as resistance for sound and fire. These blocks have no coarse aggregates. In this paper, the used materials for producing aerated blocks are cement, sand, lime, fly ash, rice husk ash, aluminum powder, water, and superplasticizer. Rice husk ash, an eco-friendly material in which it is a waste material from the rice mills, is added to the mixture as an extra ingredient. Fly ash is an environmentally acceptable substance that is commonly used in conjunction with cement. It is a lightweight concrete of density 1600 kg/m3. The effect of rice husk ash on concrete was investigated using a compressive test. In this paper compressive strength of cubes has been tested after 28 days that are cured underwater. The compressive strength of cubes with 0.05 percent, 0.1 percent, and 0.15 percent aluminum powder changes is maintained, as is the compressive strength of cubes with 5 percent and 10% rice husk ash (RHA) variations. The water-to-cement ratio of 0.5 is maintained throughout, as well as the cement-to-sand ratio of 1:2. Eighteen blocks are cured underwater for 28 days. However, it was observed that concrete block having 5% of rice husk ash with 0.05% aluminum powder contributes more strength than other concrete blocks.