Experimental study on the mechanical performance of polypropylene fiber-reinforced concrete incorporating palm oil fuel ash as partial cement replacement

Environmental pollution caused by the disposal of palm oil fuel ash, a type of waste from the palm oil trade, needs to be resolved. At the same time, activities involved in the manufacturing of cement, which is the primary binder in commonly used concrete, have undesirable impacts on the environment. In view of environmental sustainability, the approach of using palm oil fuel ash as a pozzolanic material would contribute towards a cleaner, greener environment. The present study aimed to investigate the fresh and mechanical properties of polypropylene fibre-reinforced concrete mixed with palm oil fuel ash as a cement replacement. Six different mixtures were tested with varying weight percentages of palm oil fuel ash as a cement substitute. Water absorption, workability, compressive strength, and splitting tensile strength were among the tests conducted. Concrete loses some of its workability when palm oil fuel ash is added. The strength of the concrete increases upon incorporating 10% palm oil fuel ash, benefiting from the pozzolanic reaction, which forms a compact internal structure. Notably, at this optimal level, compressive strength improved by approximately 9.5% compared to the control mix after 28 days of curing. This study provides new insights into the underexplored area of incorporating POFA in polypropylene fibre-reinforced concrete (PFRC), where limited prior research exists, thus expanding the understanding of sustainable composite materials. The utilization of palm oil fuel waste for concrete production contributes to the development of environmentally friendly construction materials and supports sustainable building practices.