Optimization of Biogenic Supplementary Cementitious Materials in Concrete prepared from East-Indian Lemon Grass (Cymbopogon flexuosus) and Poultry Litter using Response Surface Methodology

Abstract

Abstract Developing high-quality construction materials from agricultural waste as a substitute of conventional cement is receiving immense global interest in recent times, due to issues like greenhouse gas emissions and extensive energy consumption during cement production. This study aims to investigate the compressive, flexural and split tensile strengths of concrete through the utilization of bio-based products prepared from East-Indian lemon grass (Cymbopogon flexuosus) and poultry litter as supplementary cementitious materials (SCMs). The optimization process involves Central Composite Design (CCD) based Response Surface Methodology (RSM) for modelling and statistical analyses using experimental data from the study. Analysis of variance (ANOVA) revealed the model’s significance, with coefficient of determination (R2) of 0.9956. The individual and synergistic effects of the considered factors on compressive strength were analyzed using three-dimensional response surface plot. Based on RSM analysis, concrete prepared by substituting 17.57% of Ordinary Portland cement with SCM (which was cured for 25.82 days with a water-cement ratio of 0.54), yielded the optimum compressive, flexural and split tensile strengths of 33.94 ± 0.12, 8.78 ± 0.02 and 3.06 ± 0.02 N/mm² respectively. Furthermore, the SCM-mixed concrete exhibited enhanced durability properties of the concrete structure. The findings also demonstrate the robustness of RSM as a significant tool for optimization of concrete performance. Moreover, the characterization results of pyrolytic lemon grass bio-oil (LG-BO) confirms its bioenergy potential thereby suggesting its diverse utilization in various applications.