Effects of Mix Composition on Rice Hnsk Ash (RHA) Mortar

The research is done to investigate the effects of mix composition on Rice Husk Ash (RHA) mortar. The properties of RHA mortar are analyzed by varying the mixture compositions which are water-cement ratio (w/c) of 0.60 and 0.65, binder to sand ratio of 1:3 and 1:4, and varied RHA replacement (5%, 10%, 15%,20%, 25% & 30%). This experimental research is intended to further analyze the results that have been found out by previous researcher which used the same methodology but with w/c of 0.50 and 0.55. The use of waste materials from paddy industry which is RHA saves the environment from the dumping activity ofRHA which polluted our Mother Nature. It also reduces the content of cement in mortar or concrete mixtures and thus, helps save the environment by lessening the cement production. RHA was obtained from uncontrolled combustion of rice husks at BERNAS's factory at Sungai Ranggam, Perak and grinded using Los Angeles Abrasion Machine. RHA that is used in this research has coarser grain size than cement and finer than sand. The properties of RHA mortar with different composition are analyzed by conducting three tests. The compressive strength test is conducted at 7, 28 and 60 days of curing period. The initial rate of suction (IRS) test and water absorption test are conducted after 60 days of curing. The results show that the addition ofRHA at 5% with 0.65 w/c and 1:4 binder to sand ratio resulted in highest compressive strength than respective control and RHA mortars. This research also found out that incorporation of RHA in the mortar with 1:3 binder to sand ratio did not give any significant contribution towards the properties of the mortar