Strength and water absorption properties of lightweight concrete brick containing expanded polystyrene and palm oil fuel ash

This paper is focusing on strength and water absorption properties of lightweight concrete brick containing Expanded Polystyrene (EPS) and Palm Oil Fuel Ash (POFA) as partial replacement materials of fine aggregates and cement respectively. EPS has been chosen as lightweight aggregates material due to its characteristic which is extremely light. Meanwhile, POFA has been chosen as cement replacement due to the cementitious characteristic which could act as the binder in the concrete mixture. The replacement percentage of EPS is 0%, 20%, 30%, 40% and 50% whilst the replacement percentage of POFA is 0%, 5%, 10%, 15%, 20% and 25%. The brick properties that have been investigated in this study are density, water absorption and compressive strength. Based on the experimental results, the density and compressive strength of the brick is decreased as the percentage of the replacement increased. Meanwhile, for water absorption, it was found that the percentage of water absorption of brick was increased as the percentage of POFA increased, and it was decreased as the percentage of EPS increased. Based on the findings, the properties obtained has satisfied the requirement where the brick density for lightweight should be less than 1680 kg/m3 and the strength for load bearing and non-load bearing brick is 11.7 MPa and 3.45 MPa for each individual unit. Meanwhile, for water absorption, the percentage of water absorption of brick should be less than 12% [1,2]. From this study, it was found that, the replacement of sand and cement by EPS and POFA give significant impact towards density, strength and water absorption performance of concrete brick.