Influence of rice husk ash (RHA) on the properties of self-compacting concrete: A review

Solid waste management of waste materials or byproducts is a serious environmental issue. One such byproduct is rice husk ash (RHA). It is obtained by burning of rice husk and produces reactive amorphous silica which contains approximately 90% silica. The pozzolanic nature of RHA due to high silica content makes it a valuable supplementary cementitious material (SCM) for utilization in cement-based materials. RHA can be used in making self-compacting concrete (SCC). Research in this direction has been reported by several researchers. In this paper, review of the work done on the RHA's physical, chemical properties, SEM and XRD analysis, and effect of RHA on fresh, strength and durability of SCC is presented. Due to its pozzolanic nature, RHA significantly influences the properties of Self-Compacting concrete. Incorporation of 10-15% RHA as partial replacement of cement enhances strength and durability properties of SCC. Research on the role of RHA in SCC, will not only make its utilization in SCC, but will reduce land-filling costs and also provides a cleaner sustainable environmental solution in saving energy and reducing carbon dioxide generation by cement consumption.