Im Dezember 2020 wurde im Straßennetz des Bundeslands Niederösterreich eine Teststrecke in White-Topping-Bauweise errichtet. Ziel dieser Versuchsstrecke ist es, wichtige Erfahrungen mit dem Einsatz neuer Betonzusammensetzungen zu sammeln sowie Erkenntnisse zur Dimensionierung dieser Bauweise zu gewinnen. Dafür wurden Dehnungs- und Temperatursensoren als Instrumente für ein Monitoring eingebaut. Die vom Forschungsverein „Nachhaltige Betonstraßen“ gewonnenen Erkenntnisse über die White-Topping-Bauweise sind Basis für die Erstellung einer neuen Richtlinie in Österreich.
White topping new approaches to dimensioning and practical construction implementation
In December 2020, a test section using the white topping construction method was built in the road grid of the federal state of Lower Austria. The aim of this test section is to gather important experience with the use of new concrete compositions and to gain insights into the dimensioning of this construction method. For this purpose, expansion and temperature sensors were installed as instruments for monitoring. The knowledge gained by the ”Sustainable Concrete Roads“ research association about the white-topping construction method forms the basis for the creation of a new guideline in Austria. The realisation of the test section showed that the white topping construction method for upgrading and repairing highly stressed asphalt traffic areas is also easily possible for larger areas by means of paver installation. In addition, the tests showed that special concrete compositions adapted to the lower-ranking road network can also be used to produce greater paving thicknesses cost-effectively, making it possible to dispense with the longitudinal joint in the centre of the carriageway. In addition, a design catalogue is now available which, based on the familiar dimensioning concept from RVS 03.08.63, enables the necessary layer thicknesses to be determined quickly and easily. The structural behaviour of the white topping construction methods tested on the test section on the Lower Austrian state road L45 near Rohrendorf is to be further investigated in future with the help of the installed sensor technology and the durability checked. The knowledge gained from the research project and from the realisation of the test section will serve as the basis for the creation of a new FSV guideline for the repair of asphalt roads using the white-topping method (RVS 08.17.05).