Sustainable paving block solutions: enhancing cement paste properties through banana fiber integration

Purpose This work aims to improve the performance of cement-based materials for paving block applications by evaluating the influence of banana fibers (Ba-F) on the mechanical and physical properties of cement paste, addressing the demand for sustainable, low-cost alternatives to synthetic fibers. Design/methodology/approach Five cement paste mixes containing 0%, 0.5%, 1%, 1.5% and 2% Ba-F by volume were prepared and tested over a 90-day curing period. Physical properties (density, ultrasonic pulse velocity (UPV), total water absorption, sorptivity) and mechanical properties (compressive and flexural strength) were evaluated according to ASTM standards. Capillary-diffusive and hyperbolic models were applied to predict moisture transport and compressive strength development. Findings A 0.5% Ba-F addition improved compressive and flexural strengths by 3.6 and 8.6%, respectively, compared to the control, with minimal impact on density. Higher Ba-F dosages (>0.5%) reduced strength and UPV while increasing water absorption and sorptivity. Strong correlations (R2 ≥ 0.9) were observed between compressive strength, ultrasonic pulse velocity and flexural strength. However, negative correlation was noticed between compressive strength and water absorption. Originality/value This study provides paste-scale evidence on banana-fiber reinforcement by combining (1) UPV-based nondestructive assessment, (2) absorption/sorptivity characterization interpreted through a capillary–diffusive model (yielding transport parameters) and (3) strength development captured by a hyperbolic model, enabling identification of an optimum fiber dosage for paving-block-oriented applications.