Performance of surface modification on bio-based aggregate for high strength lightweight concrete

The utilization of wastes in concrete as bio-based aggregate can alleviate disposal issues as well as preserve precious natural resources. This research highlights the wet grout binder derived from different water-cement ratios (0.65, 0.85, 1.05, and 1.25) in modifying the surface of lightweight bio-based coarse aggregate (LWBCA). In this research, the strength properties of lightweight aggregate concrete (LWAC) mixed with modified LWBCA were evaluated. The outcomes showed that through the replacement of non-treated bio-based aggregate with that of pre-treated grout coating bio-based aggregate, the density of the samples slightly increased. The results indicated that the slump value of the treated LWBCA showed a significant enhancement by almost 45% at 10 min for treated dura oil palm shell at 0.65 water-cement ratios (TDOPS/0.65), as compared to the non-treated bio-based aggregate. In addition, the strength of the TDOPS/0.65 mix shows more appropriate quality enhancement of pre-treated LWBCA when compared to non-treated, and correspondingly the strength properties of the concrete, particularly the significant increment of compressive strength and elastic modulus were recorded at 21% and 31%, respectively. Based on the water absorption test assessment, the LWBCA concrete indicated that good concrete was obtained for all the mixes. Therefore, a new technique of surface modification on bio-based aggregate has shown to be a highly suggested method, which performs as one of the most promising solutions to enhance the interfacial bonding strength. Thus, treatment improves the bio-aggregates to a level without scarifying the quality of the LWAC and substantially mitigating the environmental impact in concrete.