Review paper on utilization potential of rice husk ash as supplementary cementitious material

Abstract

This paper review the work of eminent scholar in field of use of rice husk ash in concrete as a supplementary cementitious material, rice husk is proven as good pozzolonic material by various researchers. Distinctive conclusion from several researches has been demonstrated here, emphasizing on the fresh, hardened and durability properties of concrete when blended with Rice husk ash (RHA). The result shows a considerable enhancement in the sorptivity and electrical resistance with age and blending percentage. It is found that the compressive strength shows a marked increase when blended with RHA. Increased sulphate resistance, considerable reduction in rapid chloride penetration is also observed in RHA-blended concrete. The autogenous shrinkage of normal and high performance concretes is also reduced considerably. An added benefit of RHA is to improve in fresh concrete properties like segregation and bleeding, which is commonly observed in self-compacting concrete as well as concrete containing lightweight aggregate. RHA is also found out to be good pozzolanic admixture to produce Ultra High-Performance Concrete without significant change in compressive strength. The high water demand in RHA-blended concrete is due to its mesostructure, high specific surface area and particle shape, thus higher SP dosage is required to maintain the workability. In coarse aggregate concretes, RHA enhance the durability of concrete by decreasing the portlandite content, refinement of the pore structure thus reduces the thickness of the interfacial transition zone (ITZ) between aggregate and cement matrix. India is the second largest rice producing country, and the disposal husk is a major environmental problem. There is a lot of deliberation for disposing them by making commercial and economically viable use of this RHA.