Taguchi experimental matrix optimization of two plant-based concretes with sargassum (Sargassum fluitans) and peanut shell (Arachis hypogaea) aggregate

The current research focused on improving two concrete mixes that contain a Portland cement and fly ash base, along with plant aggregates made from peanut shells (Arachis hypogaea) and sargassum (Sargassum fluitans) to obtain the configuration that would provide the best possible compressive strength (of at least 2 MPa to making them feasible for use in construction), but with the best thermal conductivity properties (lowest value) to improve the insulating capacity of the material. A full orthogonal array (Taguchi, P = 3 and L = 3) with three parameters (water/binder ratio, aggregate/binder ratio, and fly ash use) at three levels was employed to identify the optimized configuration. Additionally, the samples underwent morphological analysis to assess the treatments' efficacy and the compatibility of the raw materials. The statistical analysis revealed that the M5 samples exhibited the optimal compressive strength of 4.01 and 4.22 MPa for the concretes with peanut and sargassum. The thermal conductivity was lower than 0.37 W/mK, representing a reduction of approximately 75% compared to a conventional mortar. This demonstrates that the appropriate dosage of the compound allows for attaining optimized properties for non-structural applications in buildings.