Well-functioning infrastructure and a good mobility are important prerequisites for economic growth in Denmark. Railways play an important role in this regard. Improved mobility calls for a faster rail traffic and therefore there is a need for rail network to explore modern technical solutions to enable world class comfort to citizens traveling around the country.
With the increase in the intensity and speed of the train traffic, there is significant increase in the wear and tear of the rails. This demands for a higher maintenance of the infrastructure.
This project"Roads2Rails" (R2R) aims to develop and introduce a new high-quality railway structure which requires less maintenance and has a longer lifespan than the existing system. The result will be a railway, which is more favorable seen from a total economic perspective.
For more than a century railways have been designed with tracks and sleepers resting on ballast layers. This research and development project, "Roads2Rails", will investigate the possibility of eventually replacing the ballast layer with durable asphalt – which will be specially developed for this purpose. This research and development project has been awarded an investment from Innovation Fund Denmark.
- In a railway with traditional structure, the wear of the ballast increases with increasing train speed and train intensity. "Roads2Rails" thesis checks the use of asphalt in the structure to significantly reduce the wear on the overall construction.
- Use of asphalt in the construction may reduce the total height of the rail-bearing construction, which gives obvious advantages e.g. in connection with constructions of tunnels.
- In railway structures, which are based on friction materials such as the case is for traditional railways, the load bearing layers in the rail-bearing construction are essential to ensure a low water content in view of the stability of these layers. The traditional ballasted solution allows water to sink unobstructed to the lower layers, which is unproblematic in a normal situation. However, future climate change can pose some serious challenges that may require extensive drainage measures. According to Ole Grann Andersson, technical manager at the Danish Technological Institute, by using asphalt ,"lids" are laid on top of the lower layers to prevent the seepage of water sinking into the lower layers. Further, Andersson emphasizes, that the this project uses many sustainable solutions like recycled asphalt.
If "Roads2Rails" project is successful in developing an asphalt solution to replace the ballast under the tracks, it caters foundation for a new market for the Danish asphalt industry which will increase the opportunities for other Danish workplaces, and increase technological exports.
The project, "Roads2Rails", will develop a mathematical model for evaluating the function of new railway structures, degradation and safety, for the purpose of uncovering the consequences of different materials and structures. At the same time, the project will develop special, suitable asphalt types based on recycled asphalt. The asphalt-based system will be thoroughly tested in a specially designed test stand, which simulates full-scale loading where the tests and measurements performed will be used to validate the mathematical model.
The success criterion for the project is, the advantage of the newly developed concept that can be established through life-cycle considerations (LCA and LCC). In that way a more long-lasting and sustainable solution than the one used in the present day is ensured.
The purpose of the "Roads2Rails" project is to ensure a more undisturbed train operation, by reducing the need for maintenance of the rail network, and making the construction more robust to withstand future climate change. Development of an LCC-optimized asphalt track construction has great potential for the Danish asphalt industry on both domestic and export markets.