Abstract:

Research has shown that Rice Husk Ash (RHA), an agricultural waste exhibits cementitious properties in the presence of lime. However, in Nigeria, the use of RHA as a construction material has not been fully utilized despite its benefits in terms of sustainability. In this study, RHA was used to partially replace Portland cement at 10% to form a Cement-RHA mortar composite at a 1:6 ratio of binder to aggregate. Nano-polymer, (Elastobar) was added at: 0%, 1.5%, 3.0%, 4.5% and 6.0% of the weight of binder. Mortar specimens of 100mm by 100mm were prepared and cured for 7, 14, 21 and 28 days 7, 14, 21 and 28 days respectively. Mortar properties investigated include compressive strength, thermal conductivity, fire resistance, sorptivity and water absorption. The results showed an increase in the density and compressive strength of RHA-Cement mortars, with a corresponding decrease in water absorption and sorptivity, following the addition of nano-polymer. Also, thermo-physical properties such as thermal conductivity and fire resistance were improved. The decrease in thermal conductivity indicates better insulating properties of the mortar, while the decrease in water absorption indicates a better waterproofing material. The observed improvements are significant from durability and sustainability perspectives.