Mechanical properties of cement mortar with Lime & Rice hush ash

Abstract

Hardening of cement-based mortars along with rice husk ash and lime in various formulations was studied using mechanical strength. As cement is partially substituted with RHA; the combined hydration of (OPC) cement, carbonation reaction, and pozzolanic reaction result in hardening. Although hydration of cement contributes to boost the mortar early strength, at the later stages, carbonation becomes much greater as its cement level decreases and the mortar’s porosity increases. The long-term strength growth of cement–rice husk Ash mortars is below that of the reference cement (OPC) mortar due to its higher porosity resulting from high demands of water in Rice husk ash grains. For cement-Rice-husk Ash – lime mortars with 10 percent cement weight, the reduction in strength is observed at an early stage. It has been clarified that the current phase of calcium silicate hydrate (C–S–H) is insufficiently cemented and carbonated.