Properties of clay-sand-rice husk ash mixed bricks

Abstract Bricks were made from clay-sand mixes with different percentages of rice husk ash and burnt in a furnace for different firing times. The firing durations at 1000°C were 2 hours, 4 hours and 6 hours. The effects of rice husk ash contents on workable mixing water content, Atterberg limits, linear shrinkage, density, compressive strength and water absorption of the bricks were investigated. Test results indicated that lightweight bricks could be manuctured with rice husk ash without any deterioration in the quality of bricks. Further, the compressive strength of the bricks was higher with rice husk ash contents. The optimum firing duration was found to be 4 hours at 1000°C. It is shown that bricks made of clay-sand-rice husk ash mixes can be used in load bearing walls.