Effects of fiber added on the fundamental and viscoelastic properties of Asphalt mixtures used for pavement coatings

Abstract

One of the most common distresses of asphalt concrete pavement in Vietnam is rutting under important impacts of overloaded vehicles. A part from controlling the quality of underneath layers, one can consider to use modified bitumen, improve the gradation curve of the mixtures, or add other additives to the mixture such as fiber to enhance the service life of the pavement. In this study, Forta-fi fiber was used at a content of 0.1% of the total mixture weight. The results showed that Fortafi fiber improves fundamental properties of asphalt mixtures such as Marshall stability and flow, indirect tensile strength. Regarding viscoelastic properties, when adding Forta-fi fiber to the mixture, the fiber-reinforced asphalt concrete sample showed an increase of dynamic modulus of approximately 15% when the frequency of the applied load is low or at high temperature. Fiber was found to do not affect the horizontal shifting coefficient when constructing the master curve of the dynamic modulus as well as the phase angle of the asphalt concrete material. The results also showed the ability of Huet-Sayegh in predicting well the viscoelastic behavior of both fiber and non-fiber asphalt concrete.

Keywords: Asphalt Mixture; marshall stability; flow; Forta-fi fiber; indirect tensile strength; huet-sayegh model