CARPET

 

Continuously Assembled Rollable Polymer-Embedded Topping for Roads

    Copyright: © ISAC

The high density and great quality of the road network have played a major role in Germany's current economic strength. The importance of its performance and availability will continue to increase in view of the growth forecasts for road freight transport in particular. The materials, production and paving methods used in road construction have not changed significantly over the past five decades. The quality of conventionally constructed road sections varies considerably in some cases, the limitations of bitumen as a binder are evident today, especially in the formation of ruts, the time required for rehabilitation work is high and the labor-intensive work close to ongoing traffic is dangerous.

The aim of this project is to research a road surface layer that is manufactured in an industrially reproducible manner using modern methods, in which new materials are specifically processed for improved skid resistance, sound absorption and water drainage, among other things, and which will in future house a sensor system that detects relevant traffic and environmental conditions from within the road.

CARPET: Functionalities and paving concept

Initial experience with new manufacturing and paving methods is available with a stationary manufactured roll-on road surface course from the Netherlands, which is rolled out again on site and bonded to the subgrade. This surface course, however, is still produced on a bitumen basis and the aggregate is conventionally rolled on at the factory. But the possibility of industrial, reproducible production of surface courses opens up the prospect of other fundamental innovations in road construction. In the approach pursued here, for example, bitumen is not used because preliminary tests have shown that other polymer-based binders have better mechanical properties. The design of the new surface course is also based on models with the aim of improving skid resistance, sound absorption, water drainage and the durability of these characteristics under practical conditions (traffic, weather, contamination) and while ensuring stability.

Rollable road surface from the Netherlands

The rollable road surface ("CARPET") to be developed will initially be designed for use on an open-pore asphalt in the context of new road construction and fundamental renewal.

In this project, the development of the CARPET as well as the production of prototypes and their mechanical and scanning electron microscopic characterization will be carried out by the DWI at RWTH Aachen e.V.. At the Institute for Road Research ISAC, the theory of rubber friction is being further developed for application to the CARPET in order to subsequently be able to specify an optimum texture for it. The selection and arrangement of the mineral aggregates in the manufacture of the CARPET is being carried out with the aim of researching a surface that retains the same grip when rock knolls are worked off or broken out, by the teaching and research field of clay and interface mineralogy CIM as part of the project applied for by ISAC.

Publications

• "Die Straße der Zukunft - Konzepte und Potentiale der Straßenbautechnologie der Zukunft"