Winter maintenance as a part of road maintenance defnes the accessibility during the winter period and is therefore of high importance for the people and the economy in Austria. Due to the high costs and necessary resources for 120 to 150 winter maintenance days per year it also plays an important role for road authorities. Winter maintenance contributes to approximately 20% of operating costs for regional roads and 25% to 30% on highways in Austria, respectively. Furthermore, road authorities are held responsible by public opinion to provide high level of standard and accessibility at all times. In order to improve the winter maintenance techniques, the federal states, the Austrian highway operating company ASFINAG and the federal ministry of Transport (BMVIT) funded a research project at the Institute of Transportation (Vienna University of Technology). The goal was to investigate the question of the necessary salt application rate and timing in order to optimize winter maintenance and improve the road safety. The developed mathematical model allows a determination of the necessary application rate and timing of de-icing agents as a function of snow fall, traffc and road surface temperature and texture over several treatment cycles. Based on extensive feld research the resulting skid resistance and speed limits for safe driving can be estimated with the model as well. For the implementation of the fndings, a compact summary and a winter maintenance guide were developed. Based on typical winter weather and road conditions, practical winter maintenance recommendations and application rates are given. The winter maintenance guide was tested in winter 2010/11 on selected roads in Austria and will be available starting with the winter period 2011/2012. (Author/publisher)
Samenvatting