The paving method

The “hot on hot“ paving method

In the majority of countries all over the world, roads are constructed in the conventional manner by building up asphalt pavements in layers. After the anti-freeze layer gravel and crushed-stone base courses are placed as well as an asphalt base, followed by asphalt binder and finally by surface courses. Today‘s massively growing traffic volume and above all the rise in heavy vehicle figures and axle loads lead to an increasingly higher stress on the roadway as a structure. In the wake, conventional road construction is facing new challenges.

The two-layer construction of asphalt pavements by “hot on hot“ paving is a particularly efficient method of building long-lasting roads. When using this method, binder and surface courses of hot rolled asphalt are laid “hot on hot“. This offers a number of advantages.

The advantages of the process
1. Cost savings

Economy of expensive surface course mix, rich in bitumen, in favour of low-cost binder material featuring higher stiffness and resistance to deformation cuts costs. There is no need to spray bitumen emulsion, which saves time and material.

2. Longer service lives of road pavements

Optimal interlocking of binder and surface courses guarantees an excellent bond between layers. Furthermore, compaction of the surface course with a low but sufficient voids content is supported, thus prolonging the pavement’s service life considerably. Using a higher proportion of binder course mix with a high resistance to deformation and a lower proportion of bitumen-rich surface course mix increases the pavement’s stability. Deformation and rutting are reduced substantially.

3. Paving during the cold season

Two-layer paving increases the pavement’s heat storage capacity. The period of time available for compaction is prolonged, so that paving work can be carried out to a high standard of quality even in cold weather.