Highly stable asphalt binding layers

Asphalt binding layers connect the base course to the surface course. Most shearing stress is transferred in the binder layer, which possess specific requirements for their stability and deformation resilience. They are intended for asphalt roads of load classes BK 100, BK 32, BK 10 and BK 3,2 according to RStO 12.

Highly stable asphalt binding layers are similar to the SMA mix design with a coarser aggregate share and are used for high load traffic roads. The mixture, with a relatively high bitumen content, has the tendency to drain off. This is countered by addition of CFF cellulose fibres.

The void content of the SMA binder layer is relatively low. For this reason it is the perfect binder course for porous surface layers with the intention to prevent permeability of water into base courses.

The same effect is preferable under mastic asphalt surfaces. The low void content of the SMA binder prevents the enclosure of water or moist between the layers which could force bubbling of the mastic asphalt.

Highly stable binding layers have proven their worth in:

• motorways
• crossing areas and bus stops
• heavy load traffic areas