Mechanical and microstructure properties of cassava peel ash-based kenaf bio-fibrous concrete composites

Abstract

The study investigated the effects of kenaf bio-fibre (KBF) and cassava peel ash (CPA) on the physical, mechanical and microstructural properties of concrete. The CPA was characterized by microstructural studies such as X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray spectroscopy (EDS). The KBF (length, L = 5 cm) and five (5) volume fractions from 0 to 1.0% (Δ% = 0.25%) were used with Portland cement (CEM 1). Next, five concrete mixtures were also cast using 10% CPA as a replacement for CEM 1. The results revealed that the inclusion of KBF in concrete and blending CPA with CEM 1 reduced the slump values with no major improvement of the compressive strength. However, blending CPA with CEM 1 and inclusion of KBF in concrete improved the VeBe time of the fresh concrete and the tensile and flexural strengths of the hardened concrete. The SEM results showed that KBF serve as bridges between the cracks and enhanced the load transfer capability of the concrete matrix. Overall, the study demonstrated that the utilization of KBF and CPA in concrete is a technically feasible and environmentally friendly approach to waste valorization and sustainable construction.