Natural fiber biocomposites: A comprehensive review of current developments and material properties of plant and animal fiber reinforcements in cement concrete, and ultra-high-performance concrete
Olajesu Favor Olanrewaju, Isiaka Oluwole Oladele, Samson Oluwagbenga Adelani
Abstract
Fiber reinforcements are used in concrete manufacturing to prevent brittle failure, enhance workability, and improve spalling resistance. This study introduces an integrated experimental, analytical, and machine learning (ML)-based framework for designing and optimizing sustainable Natural Fiber Reinforced Conventional Concrete (NFRCC) and Ultra-High-Performance Concrete (NFRUHPC). It systematically evaluates the effects of various natural fibers such as jute, sisal, coconut, ramie, wool, flax, bamboo, and basalt on the mechanical performance, density, and sustainability of concrete composites. Quantitative results show that incorporating 0.4 wt% jute fiber increased compressive strength by 20.2 % (44.44 N/mm²), while optimal fiber contents (1.5–2.0 wt%) improved strength by 9–20 % across fiber types. Tensile strength enhancements reached up to 137.7 % for jute and 103.8 % for sisal, with treated henequen and human hair fibers improving tensile capacity by 98 % and 22 %, respectively. Flexural strength rose by 8.7–54.5 %, and 10–20 wt% eggshell powder substitution enhanced compressive and flexural strengths by up to 5.88 %, improving strength-to-weight ratios. Impact energy absorption increased by 60–138 %, with coir fiber composites absorbing up to 253.5 J, demonstrating improved ductility. For NFRUHPC, 2 % hybrid sisal fibers enhanced peak displacement by 31.3 %, dynamic tensile strength, and energy absorption (916.51 J). Macro basalt fibers improved compressive and flexural strengths by 21.3 % and 40 %, respectively, while toughness rose 548–765 %. To complement experimental work, ML models using Gradient Boosting and Artificial Intelligence techniques accurately predicted mechanical properties (R² ≈ 1), identified critical parameters (fiber geometry, curing time, W/B ratio), and reduced design uncertainty. This data-driven, performance-based design framework offers a scalable pathway for eco-efficient, high-strength concretes that advance sustainable infrastructure development.