Rice husk ash as a sustainable supplementary cementitious material for improved concrete properties

There is a wide range of research worldwide on supplementary cementitious materials (SCMs) such as fly ash, slag and silica fumes that have pozzolanic properties sufficient for substituting ordinary Portland cement (OPC). These SCMs are known to significantly improve concrete properties, especially in terms of increased strength and durability. Unfortunately, the production of such SCMs is becoming scarce and limited to certain parts of the world. Hence, alternative options must be sought that bear in mind the ever-increasing importance of the issue of availability of resources as well as the appeal of using of eco-friendlier SCMs in a cementitious system. This paper addresses the use of rice husk ash (RHA) as a sustainable replacement for cement. Despite the fact that extensive research has been done on this material, its application in a cementitious system to obtain sufficient concrete properties is still rather limited. This paper explains the possibility of obtaining a ternary cementitious system consisting of OPC, RHA and other readily available resources such as limestone filler (LSF) and the performance of the blended systems in the presence of superplasticizers. The outcome is to produce normal strength concrete with good performance – optimum workability and durability.