Optimization of Grinding & Grooving of concrete road surfaces
A third of the Austrian motorway network is built as exposed aggregate concrete, which has beneficial noise properties. Concrete sections built before the 1990s were done using brushing. Concrete pavements are – if done properly – long lasting and require little maintenance. However, with increasing age, maintenance measures to rehabilitate in particular sufficient skid resistance are necessary. The Austrian regulation RVS 13.01.51 “Maintenance of Concrete Pavements” describes different maintenance measures. Among others, grinding and grooving are mentioned in the current version of the RVS, but no details on the implementation are given.
The aim of the project “Groove” was to provide and optimise the geometric properties of grinding and grooving surfaces in the laboratory and on trial sections in-situ. It considers both current construction types in Austria, exposed aggregate concrete and brushing. On two motorway sections, different grinding and grooving textures were applied and the development of the surface properties of noise emission, skid resistance and evenness were monitored over a period of 1 to 1.5 years. The increase in skid resistance achieved by the grinding is no longer present at the end of the observation period, while the improvement in longitudinal evenness is unchanged. The reduction of rolling noise achieved by the grinding was just as durable.
After compiling existing measurement results, a concept for the laboratory work was developed. Test specimen with different concretes were then produced in the laboratory and durability tests were carried out with regard to weather impact and traffic loads and compared to samples from the motorway. In addition, the robustness of different textures against a traffic load was examined. The laboratory results showed that sufficient durability of skid resistance on the test tracks was expected from the applied grinding texture. Also, in direct comparison to the exposed aggregate concrete surface, the different grinding textures showed an equal skid resistance behaviour.
Finally, a text proposal for the extension of RVS "Maintenance of Concrete Pavements" regarding Grinding and Grooving was drafted for the responsible FSV working committee.
Funded by the Federal Ministry for Climate Protection, Environment, Energy, Mobility, Innovation and Technology (BMK) and the Austrian Research Promotion Agency (FFG) as part of the Mobility of the Future program.
