Research Article ImpactofAdditionofBananaFibresatVaryingFibreLengthand Content on Mechanical and Microstructural Properties of Concrete RodgersB.Mugume ,AdolphKarubanga,andMichaelKyakula Department of Civil and Environmental Engineering, Kyambogo University, Kampala, P.O. Box, 1, Kyambogo, Uganda Correspondence should be addressed to Rodgers B. Mugume; rmugume@kyu.ac.ug Received 14 April 2021; Accepted 30 September 2021; Published 8 October 2021 Academic Editor: Rahul V. Ralegaonkar Copyright © 2021 Rodgers B. Mugume et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. is experimental study aimed at investigating the impact of addition of banana fibres on the mechanical (compression, splitting tension, and flexure) and microstructural (microscopic morphology and Energy Dispersive X-ray Spectroscopy) properties of concrete. Concrete mixes comprising of banana fibres of varying fibre lengths (40, 50, and 60 mm) and fibre contents (0.1, 0.2, 1.0, 1.5, and 2.5%) were assessed. Addition of banana fibres to concrete was observed to significantly impact on compressive strength only at lower fibre contents of up to 0.25% for all fibre lengths. Fibre length had no significant impact on compressive strength at lower fibre contents of up to 0.25%, but shorter fibres were observed to perform better than longer ones at higher dosages more than 0.25%. Increase in fibre content positively impacted on tensile strength of concrete at relatively lower fibre dosages of up to 1%. Similarly, fibre length impacted on tensile strength of concrete at lower fibre contents of up to 1% and, longer fibres were observed to be more effective than shorter ones. Addition of banana fibres generally did not greatly contribute to flexural strength of concrete but had a marginal impact only when shorter fibres were used at lower fibre dosages. Also, microstructure of concrete was improved through better bonding between the fibres and the matrix and reduction in porosity of the matrix, which resulted in improved mechanical properties of the composite. Banana fibres further contributed to changes in phases of the composite structure of Banana fibre-reinforced concrete (BFRC) through a reduction in its interplanar spacing and lattice structure. For optimal purposes, addition of banana fibres should be limited to a maximum of 1% fibre content preferably using shorter fibre lengths. Further research to improve flexural strength of BFRC to meet minimum technical requirements is required before it can be considered for structural applications. 1.Introduction Concrete is one of the most widely used material in the construction industry because it offers good strength and durability properties, and its primary constituents are readily available and cheap [1–3]. Despite its numerous advantages, concrete is also well known to have several weaknesses, such as a low tensile strength capacity that is significantly lower than its higher capacity to resist com- pressive loading, brittleness, low postcracking capability, and low fracture resistance [4–10]. is makes it highly susceptible to large tensile or flexural stress-induced damages that often lead to cracking in concrete, which in turn negatively impacts on its strength and durability [6, 11, 12]. Recently, natural fibres have been advanced as an alternative reinforcing material to conventional synthetic fibresowingtotheirenvironmentalandeconomicbenefits [13–20]. Natural fibres are readily available, biodegrad- able, cheaper, and recyclable, and they have been observed to have high tensile and flexural strengths as well as low elongation at break, hence rendering them widely ac- cepted in construction industry [21–24]. Elbhiery et al. [20] compared and summarised the mechanical proper- ties of various plant fibres and E-glass. However, studies conducted on the performance of natural fibres have Hindawi Advances in Civil Engineering Volume 2021, Article ID 9422352, 15 pages https://doi.org/10.1155/2021/9422352