4 - The use of rice husk ash in concrete

Abstract

This chapter discusses the characteristics, quality, hydration mechanism, and influence of rice husk ashes on the quality of concrete. Rice husks are byproducts of rice paddy milling industries. For rice growing countries, rice husks have attracted more attention due to environmental pollution and an increasing interest in conservation of energy and resources. For developing countries where rice production is abundant, the use of rice husk ash (RHA) to substitute for cement is attractive because of its high reactivity. As the production rate of rice husk ash is about 20% of the dried rice husk, the amount of RHA generated yearly is about 20 million tons worldwide. In addition, properly treated ashes have been shown to be active within cement paste. Hence, the use of rice husk ash in concrete is important.