The Effects of Partial Replacement of Cement by Microwave Incinerated Rice Husk Ash (MIRHA) in Cement Mortar and Brick

The demand for a high quality material with sustainable designs has increased and encouraged the engineer/ researchers to find new alternatives in building technology. Rice husk generated from the rice production poses a major problem of disposal especially when open burning is no longer permitted due to the environmental issues. The usage of pozzolanic materials to reduce the carbon dioxide emitted per tonne of concrete produced are being investigated and utilized. This study investigates the potential of using Microwave Incinerator Rice Husk Ash (MIRHA) in mortar mixes made of Ordinary Portland Cement (OPC). The MIRHA used was obtained using microwave incinerator at control temperature and burning process. In the experimental study on compressive strength of cement mortar the water-binder ratio was kept constant at 0.5. Control mortar without any replacement and 5%, 10%, 15%, 20% and 25% of OPC replaced by MIRHA were studied with varied binder-sand ratio at 1:3, 1:4. 1:5 and 1:6. The compressive tests were conducted for the samples at 7 and 28 days. The result has revealed that, the MIRHA could be used in cement mortar due to its refinement microstructures. In addition to that, the compressive test results were compared with three different standards: ASTM, MS and BS for bricks manufacturing. The results show the potential of using MIRHA in cement brick production. Amongst the cement replacement mixes, 20% MIRHA has shown highest compressive strength.