Stone Mastic Asphalt (SMA)
Both in the world and in our country, ruts, i.e. grooves, formed on the roads due to increasing traffic volume and axle loads are considered as one of the most important deteriorations in the superstructure. Therefore, in order to reduce the formation of rutting and increase the life of the roads, stone mastic coatings with high bitumen ratio and high grain contact and interlocking have been developed.
Stone mastic asphalts (TMA) are generally preferred on roads with heavy vehicle traffic.
TMA mixtures are mixtures with intermittent gradation containing 70 – 80% coarse aggregate, 20 – 30% fine aggregate and 6 – 7% high bitumen. The aggregate skeleton being composed of coarse gravel causes more gaps between the aggregate particles.
These gaps are filled with fine aggregate called mastic mortar, filler, bitumen or modified bitumen and fiber that prevents the bitumen from flowing.
The main features of TMA can be listed as follows;
- • High strength and rutting resistance
- • Better structural internal resistance
- • Better slip resistance
- • Sound absorbing feature
- • Longer service time
- • Resistance to aging