Structural performance of reinforced self-compacting concrete columns produced with palm oil fuel ash

Palm oil fuel ash (POFA) is an agricultural waste produced from the palm oil industries and disposes off into an open ground without any reprocessing or profitable return, has been established to enrich concrete durability as well as mechanical properties when used to replace cement. However the POFA used to partially substitute cement in self-compacting concrete (SCC) production were done on material properties by fabricating standard specimens such as cylinders, prisms and cubes. Moreover, the utilization of POFA to partially substitute cement to cast reinforced concrete structural members is not common compared to fly ash and ground granulated blast furnace slag. This study therefore focuses on structural performance of reinforced self-compacting concrete columns produced with palm oil fuel ash. Two mixes of SCC containing 0% and 15% of POFA were prepared to fabricate the columns. The main variables considered were percentage of POFA content, percentage of steel reinforcement ratio (2% and 3%) and thickness of concrete cover (25 mm and 35 mm). Eight columns were fabricated altogether and tested under axial compression load up to failure. The results of the test revealed that the ultimate axial capacity of reinforced SCC columns produced with POFA is higher than the columns produced without POFA by approximately 2.6% and 2.2% for 25 mm and 35 mm concrete covers, and 2.9% and 2.5% for 2% and 3% steel reinforcement ratios. It is also observed that the load-deflection pattern of reinforced SCC columns produced with and without POFA follow similar trends. However, columns produced with POFA showed slightly lower stiffness than the columns produced without POFA.