There are references to reinstatement materials in various parts of the specification and the appendices. These include:
- the overall class of materials, such as hot rolled asphalts (HRA), stone mastic asphalts (SMA), asphalt concretes (AC) and traditional concretes used in some roads;
- different types of mixture within each class of material. These tend to relate to the relative position of the mixture within the overall reinstatement (e.g. AC surface course, AC binder course) and reflect the design function of the layer;
- different preferred (and permissible) mixtures for different layers;
- different thicknesses of mixture layers;
- specific requirements and limitations for surface courses.
Each of the above has been assigned to different parts of the Code and it is essential that they are taken into account when selecting the reinstatement design for a particular surface category.
The reinstatement of flexible roads (and footways) is particularly complex at the reinstatement design selection stage. To assist practitioners, Figure S0.1 sets out the intended materials selection process for flexible (and composite) carriageways.