Exploring Pine Needle Fibers in Concrete to Mitigate Flexural Spalling in Rigid Pavements

Abstract

The growing demand for durable and low-maintenance transportation infrastructure has increased
interest in cement concrete as an alternative to traditional bituminous roadways. Despite its
extended lifespan, concrete faces challenges such as low ductility, tensile strength, and
susceptibility to spalling, prompting the exploration of innovative solutions. This study explores
using pine needle fibers in concrete to improve flexural strength. Various fiber dosages (0.5% to
5% by weight) are tested on specimens (cubes, cylinders, and beams) with a 28-day curing period
to evaluate long-term effects. The study employs a comprehensive set of destructive tests,
including compression, flexural, and tensile strength assessments, as well as non-destructive tests
such as ultrasonic pulse velocity, to thoroughly analyse the structural behaviour of the concrete.
Preliminary findings suggest that the addition of pine needle fibers positively influences the
mechanical characteristics of the concrete, demonstrating promise in mitigating flexural spalling
in rigid pavements. This research improves sustainable pavement materials and enhances concrete
pavement performance. The study addresses challenges in transportation infrastructure, paving the
way for resilient and sustainable solutions in rigid pavement construction. Early findings show
pine needle fibers improve concrete mechanics, notably reducing flexural spalling in rigid
pavements. This contributes to sustainable pavement knowledge and offers practical insights for
concrete pavement enhancement.