Effects of Oil Palm Shell Coarse Aggregate Species on High Strength Lightweight Concrete

The objective of this study was to investigate the effects of different species of oil palm shell (OPS) coarse aggregates on the properties of high strength lightweight concrete (HSLWC). Original and crushed OPS coarse aggregates of different species and age categories were investigated in this study. The research focused on two OPS species (<i>dura</i> and <i>tenera</i>), in which the coarse aggregates were taken from oil palm trees of the following age categories (3–5, 6–9, and 10–15 years old). The results showed that the workability and dry density of the oil palm shell concrete (OPSC) increase with an increase in age category of OPS species. The compressive strength of specimen CD3 increases significantly compared to specimen CT3 by 21.8%. The maximum achievable 28-day and 90-day compressive strength is 54 and 56 MPa, respectively, which is within the range for 10–15-year-old crushed <i>dura</i> OPS. The water absorption was determined to be within the range for good concrete for the different species of OPSC. In addition, the ultrasonic pulse velocity (UPV) results showed that the OPS HSLWC attain good condition at the age of 3 days.