Effects of pre-treated on dura shell and tenera shell for high strength lightweight concrete

The utilization of bio-based renewable lightweight aggregates with pre-treated coating methods, using a grout binder derivative of water/cement (w/c: 1.25), is a recent development meant to enhance the performance of high strength and lightweight concrete. It aims to promote the long-term sustainability in the field of concrete technology. In this experimental analysis, coated tenera shells (CTS) and coated dura shells (CDS) acted as a replacement for tenera shells (TS) and dura shells (DS), respectively. It has previously been investigated in terms of its physical strength and associated material properties, as a lightweight bio-based aggregate concrete (LWBAC). The results revealed that through the substitution of raw TS and DS aggregates with that of CTS and CDS, the density of the samples which fell within the range of high strength lightweight concrete (HSLWC), slightly increased. As a result, the workability of the oil palm shell concrete (OPSC) showed a significant improvement by almost 41% with the use of the pre-treated OPS aggregates, as compared to the non-treated OPSC. The strength of the HSLWCs with the CDS mixture achieved the highest compressive strength and modulus of elasticity at 28-days, which were recorded at 52 MPa and 17.1 GPa, respectively. The ultrasonic pulse velocity (UPV) was also assessed, and the outcome revealed that a good condition was attained after 7 days. Therefore, pre-treated CDS and CTS has proven to be a highly recommended, eco-friendly aggregate, which serves as an alternative solution to improve the properties of OPS aggregates, and substantially enhance the performance of the LWBAC.