Recycling of concrete surfaces, prefabricated elements for quick surface repairs, surface texturing methods - these are the main directions of research in Germany in the area of concrete roads.
These topics dominated during the 13th International "Concrete Road 2018" Symposium, which took place at the end of June in Berlin. Among the German experts in this field was Ph.D eng. Marko Wieland from the BASt Federal Research Institute. He gave the ViaExpert portal an interview on the advantages of concrete roads and the most important research topics concerning the technology of construction and maintenance of roads made of cement concrete. A few days later, Dr. Wieland was also one of the hosts of a study visit of Polish road workers who were directly acquainted with the practical application of the Grooving and Grinding methods in Germany.
One of such topics is the comparison of durability of road surfaces made of asphalt and concrete. Those surveys are still in the preliminary phase: one such project is being implemented in Saxony. There are further research sections planned which will allow to draw conclusions regarding life costs of both types of surface (life cost analysis).
Such an analysis will also include information on the possibilities of recycling, i.e. re-use of materials used for road construction. We are conducting research on the behavior of recycled material from concrete pavements, we expect the first results next year, said Dr. Wieland. The construction of the research section and analytical measurements are in progress. In particular, researchers are interested in how to assess the utility value of road surfaces from asphalt and concrete at the initial stage of use, i.e. immediately after the construction of the road.
In the case of paving of concrete roads, it is assumed that new pavements will not need any renovation work during the whole cycle of road use. However, there is a need to renew or renovate roads that have been in use for a long time. In the case of renovation of a concrete road, short-term renovation of the pavement is possible, consisting in the rapid replacement of damaged concrete slabs. Such an operation - replacement of individual concrete pavement panels - is practically the only reason to carry out renovation works on the concrete pavement of highways. The new method is also going to be introduced to the currently binding guidelines as part of the update, which consists in using prefabricated concrete for the repair of the concrete surface.
Dr. Wieland also referred to the "Grinding" and "Grooving" technology that arouses great interest. Their use is an attempt to meet high requirements regarding such advantages of concrete surface as equability, roughness, noise reduction or water permeability. Due to the technological process, the roughness obtained as a result of using the Grinding technology is virtually unbeatable. In this case hard concrete is textured and therefore the surface uniformity is very good. The surface looks the same on every stretch of road. That is why we are of the opinion, said the expert, that this technology leads us to obtaining optimal textures. The standard texture, which is typical only for Grinding technology, will be an alternative to exposed aggregate concrete and will reduce noise by 2 decibels. Grinding / Grooving technology will provide good water permeability to road surfaces and even greater noise reduction. The roughness obtained as a result of this technology should last for 30 years, i.e. throughout the life of the texture, in order to avoid making any "corrections" of the surface condition during this period.