Overview
Different requirements are placed on the road surfaces of the heavily loaded primary road network. In addition to the expected durability of the construction, other performance charac-teristics are defined: skid resistance, longitudinal and transverse evenness, sufficient water drainage, rolling noise, etc. Simultaneous optimization of these properties is currently the sub-ject of research. While there has been a classification of rolling resistance properties for tires in the EU since 2012, no comparable system is known for road surfaces or specific road constructions. The influencing variables, or wavelength ranges respectively, for the rolling resistance of road-ways extend from the macrotexture to the longitudinal evenness. There are various methods for measuring the rolling resistance of pavements, but none of them is yet sufficiently developed to be already the subject of standardization.
Various re-search projects, especially in Scandinavia, are concerned with rolling resistance optimization of asphalt construction methods and their implementation in test tracks. Current road rolling resistance prediction models are based on characteristics such as MPD (Mean Profile Depth) and IRI (International Roughness Index) present in pavement management systems.
The RoWi project pursues the following objectives: First, the analysis of the pavement design on the ASFINAG network to gain insight into their influence on the energy consumption of vehicles. Furthermore, the development of an innovative method for measuring the rolling resistance by means of direct force measurement in the axis of the rolling wheel. In the same measurement, the influencing properties of texture and longitudinal evenness as well as envi-ronmental properties are recorded in the rolling track. This excludes assignment problems as well as changing environmental influences on measured data. Thirdly, based on the meas-urements, the development of an energy consumption characteristic value with which an op-timization of the rolling resistance on the motorway network is possible. Expected results of the research project are:
- Validated measuring methodology for in-situ measurement of rolling resistance of car-riageways.
- Evaluation of the environmental influences (e.g. surface temperature) on the rolling resistance measurement, in particular on the tire during the measurement.
- Regression model of the energy consumption, more precisely the rolling resistance depending on the road characteristics (evenness, texture).
- Estimation of the potential for energy saving through rolling resistance optimization of surfaces.
- Recommendation for the rolling resistance-optimized pavement design on the motor-way network and classification in the range of decarbonization measures.