Fly Ash for Stone Matrix Asphalt - Technical Bulletin

Stone Matrix Asphalt (SMA) is a durable, stable, rut-resistant hot mix asphalt (HMA) consisting of two parts: a coarse aggregate skeleton and an asphalt rich binder mortar. The coarse aggregate provides stone-on-stone contact for bearing and rut resistance. The asphalt rich binder provides sufficient mortar of the desired consistency for durability, requiring a large amount of mineral filler such as fly ash to convert the fluid asphalt into asphalt mastic.