Mechanical performance of fibers in hot mix asphalt: A review

The use of fibers in hot mix asphalt (HMA) has become a much more attractive alternative for the construction of road pavements. Numerous studies have shown that the incorporation of fibers in the mixture improves fatigue resistance, permanent deformation and stiffness. The aim of this paper is to present a review of the mechanical impact of fibers in HMA by analyzing their reinforcement effect in a qualitative and quantitative manner. Fiber properties and characterization tests on fiber-modified bitumen are discussed. Quantities, blending procedures and performance of bituminous mixtures with different types of fibers are presented. Results of mechanical improvement are displayed. Based on the current research results, depending on the properties and the type of mixture in which they are used, each type of fiber seems to improve certain parameters more than others. Coconut fibers and waste fibers are described as environmentally friendly alternatives. (C) 2018 Elsevier Ltd. All rights reserved.