Mechanical and fresh properties of sustainable oil palm shell lightweight concrete incorporating palm oil fuel ash

In this investigation, agro-solid waste materials from the palm oil industry such as oil palm shell (OPS) and palm oil fuel ash (POFA) were utilized to replace conventional concrete-making materials to produce lightweight concrete. The OPS was used as replacement for conventional coarse aggregate while ground POFA was used at partial cement replacement levels of up to 25%. The inclusion of POFA up to 25% did not detrimentally affect the fresh concrete properties while the use of POFA at 10-15% replacement levels improved the compressive strength of OPS concrete (OPSC). Although there was little effect of POFA on the modulus of elasticity, increased POFA replacement levels led to reduction in both the splitting and flexural tensile strengths of OPSC. The evaluation of the cost and eco-efficiencies showed that inclusion of 10% POFA gave the most optimum performance in terms of the sustainability of the OPSC.