Investigation about Marshall Stiffness index, flexural stiffness and fatigue life of Stone Matrix Asphalt with different fibers stabilizers

In early 1970s European road industry felt the need for a pavement that resists rutting, wearing out and the damage caused by heavy traffic load and studded tires. In order to address this need, officials have developed Stone Matrix Asphalt (SMA). High value of coarse aggregate, use of large amount of asphalt binder and thickness of asphalt film around the coarse aggregate in SMA are the main reasons for drain down, flushing and bleeding during the storage, transportation and placing. So as to decrease these weaknesses, stabilizers for thickening of binder and increasing the viscosity are used. Fibers are one of the materials used for this purpose, that is, Fibers use to reinforce and stabilize of this mixture. Common types of fibers used for these applications are cellulose and mineral. Aim of present study is to investigate the feasibility of using Acrylic, Jute, Polyester, polypropylene and Viscose fibers as stabilizer which are gather from native and waste material resources and to determine their effect on drain down and fatigue strength of the mixtures. In this experimental research, mixture with cellulose fibers has higher asphalt content than synthetic fibers therefore synthetic fibers are more economical. By reducing the amount of the most expensive constituent of an asphalt mixture (asphalt binder), the result could be more cost effective pavements. Flexural stiffness and fatigue life of SMA mixtures containing fibers are compared. Flexural stiffness of mixtures containing Acrylic was higher at different applied strain level compared to others. The mixtures containing Acrylic and Jute fibers show significant increase in their fatigue life.