MICROSTRUCTURAL CHARACTERIZATION OF RICE HUSK AND RESIDUAL ASH FOR THE PRODUCTION OF SUPERIOR BLENDED CONCRETE

Abstract

Several industrial by-products such as fly ash, silica fume and slag are widely used as supplementary cementitious materials in concrete. In addition to attain designed characteristic strength of structural concrete, it is very imperative to maintain the strength throughout service life of the structure. Supplementary cementitious materials are commonly used in the modern cement manufacturing process to achieve durable and sustainable concrete. Earlier research studies have clearly reported that higher strength and significant reduction in permeability of concrete containing agricultural waste products such as sugarcane bagasse ash and rice husk ash compared to control concrete. However, utilization of rice husk ash and sugarcane bagasse ash in blended cement production is limited to a greater extend as a consequence of lack of understanding and characterization of these materials. Microstructure of rice husk and silica distribution in the residual ash due to controlled burning is not available in the existing literature. This paper reviews reactive silica formation in the rice husk and its residual ashes based on the microstructure and its influence on the pozzolanic performance. Moreover, rice husk ash was processed based on suitable methodology and compressive strength of mortar was found to be high compared to control specimens. Keywords: