Resilient Characteristics of Stone Matrix Asphalt Mixes

Abstract

Stone Matrix Asphalt (SMA) is a gap graded mix, characterized by high coarse aggregates, high asphalt contents and polymer or fiber additives as stabilizers. In comparison to dense graded mixtures SMA has higher proportion of coarse aggregate, lower proportion of middle size aggregate and higher proportion of mineral filler. It resists permanent deformation and has the potential for long term performance and durability. In the present study, an attempt has been made to study the resilient properties of mixtures of stone matrix asphalt made with two types of conventional binders namely bitumen 80/100 and 60/70, with 0.3% by weight of a non – conventional natural fiber, namely coconut fiber. The mixes are subjected to both static and repeated load indirect tensile strength tests. It is observed that the natural fibres have propounding effect on the resilient properties of the mixes.