The Feasibility of Using Palm Oil Ash in the Mix Design of Interlocking Compressed Brick

The conventional clay bricks, which are used mainly for the masonry wall construction, are suffering from the increase of energy price as well as environmental problems due to soil excavation and high carbon dioxide emission. The use of green interlocking compressed brick (ICB) containing palm oil fuel ash (POFA) may be the solution for these problems. However, the mix design of ICB containing POFA is not well established. This paper reports on the feasibility of using POFA in the mix design of compressed brick for the ICB production. The mixes were formulated using two different sizes of POFA, which were the ultrafine and unground POFA, and combined with the cement and sand. The results demonstrated that the compressive strength test and water absorption test satisfied the minimum limit specified for the clay masonry unit. The maximum compressive strength of 39.2 MPa was obtained with UF-10 at 24 days curing. Increasing the amount of ultrafine POFA to 40% decreases the strength to 19.26 MPa. The utilization of ultrafine POFA into bricks has produced bricks with good engineering properties compared to the unground POFA brick. Nevertheless, these results indicate significant potential of using POFA in the production of ICB for use in building construction. Application of POFA in the ICB production will help to reduce the energy consumption of the conventional clay brick firing process and reduce the environmental damages associated with the greenhouse gas emission.