Stone-Matrix Asphalt
Stone-Matrix Asphalt (SMA), also called stone mastic asphalt, was developed in Germany in the 1960s to provide heavily trafficked roads with a durable, rut-resistant wearing course using a gap-graded aggregate structure and a modified asphalt binder at elevated asphalt contents. SMA has been used worldwide since the late 1960s, and it has been used in the United States since the early 1990s. SMA is designed to improve rut resistance and durability through the use of a stable stone-on-stone skeleton held together by a rich mixture of asphalt cement, along with stabilizing agents such as fibers and/or asphalt modifiers. In the United States, SMA is primarily used to pave high-volume interstates and highways, but worldwide it has also found use on runways, racetracks, and urban streets. In addition to improved durability and rutting resistance, SMAs have been shown to be effective in reducing traffic noise. SMA is typically used as a surface course and occasionally as an intermediate course. They have also been used successfully in thin overlay and mill-and-fill resurfacing applications.
More Information —
- 1st International Conference on Stone-Matrix Asphalt Papers & Proceedings
- Advances in the Design, Production, & Construction of Stone Matrix (Mastic) Asphalt (SR 223)
- Designing and Constructing SMA Mixtures — State of the Practice (QIP 122) — under revision
- Performance and Life-Cycle Cost Benefits of Stone Matrix Asphalt (NCAT Report 10-03) — National Center for Asphalt Technology at Auburn University
- Heavy Duty Surfaces — The Arguments for SMA — European Asphalt Pavement Association