Durable and Environmental Asphalt Pavement with Plant Fiber: A State-of-the-Art Review

Utilizing treated plant fibers in fiber-modified asphalt could reduce reliance on nonrenewable resources, contributing to environmental sustainability. To promote the utilization of plant fibers in asphalt mixtures, this review focuses on elucidating the reaction mechanism of surface-treated plant fibers and the resulting performance benefits in the composite. A comprehensive review of reinforcement mechanisms of fibers in composites, particularly asphalt mixtures, is provided to gain a mechanistic understanding of how fibers enhance performance. The review incorporates multiple perspectives to provide a thorough understanding of the performance-enhancing effects of fibers within asphalt. Plant fibers have significant potential to improve several aspects of asphalt mix performance, including high-temperature stability, low-temperature crack resistance, moisture stability, and fatigue durability. These properties also influence the optimal loading and fiber length for different fiber types, and this review provides a comprehensive overview along with recommended values. In addition, microscopic studies play a critical role in understanding the mechanism of plant fibers in asphalt mixes. The review discusses the microscopic changes induced by fiber surface treatment and sheds light on their effects at a fundamental level. The review provides a holistic reference for the application of plant fibers in asphalt mixtures for guiding asphalt pavement engineering applications, and prospect on the research direction of plant fibers in asphalt mixtures.