Laboratory investigation on utilization of recycled materials in SMA mix

Abstract

SMA (stone matrix asphalt or stone mastic asphalt) was originally developed in European and German countries as impervious or highly durable wearing surface for bridge decks. But today, it is pavement surface of choice. Generally it consists of two parts, a coarse aggregate and a binder rich mortar. It is made by a mixture of crushed coarse and fine aggregates, stabilizer such as fibres or polymers, mineral filler, cement. In present research work, an attempt has been made to study the properties of SMA mixes with cellulose fibre and using recycled pavement material as well as slag in partial replacement of stone aggregates as coarse and fine aggregate grades. This research project was done to check the usage of recycled pavement material in SMA mixture by conducting Marshall test in the laboratory in which stability value and flow values was examined along with other properties of mixtures. Here IRC -SP-79 specification, aggregate gradation is taken for stone matrix asphalt. Binder used is 60/70 penetration grade bitumen. Binder content is varied as 4%, 5%, 5.5%, 6%, and 7% by weight of aggregates and fibre used is optimum fibre content at 0.3% by weight of aggregate.