Evaluation of the mechanical performance of AC mixtures with recycled fibres.

Abstract

Based on the positive results of most of the studies using virgin fibres to reinforce asphalt mixes, this work proposes the use of recycled fibres in order to go a step further in terms of environmental impact and cost-efficiency. Different experimental asphalt concrete (AC) mixtures are proposed, incorporating three types of recycled fibres. Mechanical performance is assessed through the Marshall, water sensitivity and wheel tracking tests, as well as stiffness and fatigue tests to assess dynamic performance. The results obtained from the different tests performed are analysed by means of a multi-criteria analysis to obtain the asphalt mix with the best performance. The results show that all the tested fibres are suitable for the reinforcement of asphalt mixtures, as the values obtained improved those of the reference mixture, although without reaching the behaviour of a mixture with polymer modified bitumen (PMB). The recycled aramid fibres showed the best results.

Keywords

• Asphalt mixture
• Recycled fibres
• Polymer-modified mixture
• Aramid