Several actors are in charge of constructing and maintaining road infrastructure. They may be regions or municipalities, but also managers of specific facilities such airfield strips, port areas, industrial areas, etc. All of them, however, are faced with the same challenges raised by ageing infrastructures, ever increasing traffic loads, and budget restrictions.
The quality of road infrastructure is important to all actors, but is perceived in different ways:
The Belgian Road Research Centre has a longitudinal profile analyser for continuous measurements of the road profile. The measured data can be used to quantify the longitudinal evenness of a road and to calculate inticators such as the coefficient of evenness (CP, which stands for coefficient de planéité in French) and the international roughness index (IRI). Longitudinal evenness is an important factor for the safety and comfort of road users. The high accuracy of measurement makes the APL also suitable for research purposes. The measuring wheel bumps up and down with the relief of the road. This movement causes a change in the angle formed by the wheel-bearing arm in its hinge point. An inert pendulum in the bearing arm transforms the road profile into an electric signal. The angle between the bearing arm and the pendulum is recorded every 5 cm. This allows a graphic representation of the “pseudo-profile” of the road surface. A constant survey speed of 21.6 km/h, 54 km/h or 72 km/h is required.
We do not instantly think of it when travelling on a road, but it is worth having a closer look at the road surface. Quite a few interesting characteristic properties can be derived from a road surface condition survey. The results of non-destructive measurement methods are converted into «indicators» that are easy to understand – usually a figure on a scale.
With support from the Belgian Federal Public Service Economy, SMEs, Middle Classes and Energy, BRRC operates a standards support office that goes by the acronym “NAN”. The object is to inform SMEs in the road branch and make them aware of developments in the field of standardization and, where necessary, to offer them additional support in implementing new standards (which are often mandatory).