Projekt BVFF - publicerade   BVFF nummer:  2015-046 Projekttitel  FROSTSAFE - Preventing winter damage on the Swedish roads Projektledare/Kontaktperson  Nicole Kringos Telefon  08 - 790 8700 Utförarorganisation  KTH Medutförare  - Representatives of the Swedish contractors (NCC, Skanska and PEAB) - Material and modifier suppliers (Nynas and AkzoNobel) - Representative of VTI - Representative of Trafikverket Bakgrund  Every winter, during freezing periods, road users in Sweden have to dodge potholes that seem to appear overnight and get confronted with chipped car windshields due to flying stones from the pavement surface. During these periods, accident may occur due to sudden driver maneuvering or reduced pavement surface friction. Winter maintenance is performed to minimize the effects of the winter climate on the roads and extensive road repairs are typically postponed until after the frost season, prolonging thus commuter discomfort and adding to traffic disruptions and delays long after the freezing period. After each Swedish winter, the costs due to winter maintenance and long-term road repairs are extensive and, unfortunately, current repair techniques provide only a temporary solution until the next freezing period. Once damage has occurred, water can accumulate inside the road material pores and the micro-cracks in the top layers of a pavement. Upon new freezing cycles, the phase change of water to ice crystals is again accompanied by volume expansion, leading to extra stresses inside the pavement which accumulatively leads to the un-raveling of the road surfaces throughout the winter season (and becoming mostly visible in spring). Each time a road undergoes a maintenance or repair action, new materials are needed and energy is spent on production and transportation of the materials. Traffic jams are unavoidable consequences of such repairs and pose a strain on road-users, delay otherwise on-time transport of perishable goods and contribute additional CO2 emissions. Given the extensiveness of the Swedish winters season, to ensure the economic, societal and environmental prosperity of the Swedish infrastructure, it is therefore of paramount importance to improve the resistance of the current and future road network against these winter conditions and develop effective tools and methods to assist in winter maintenance actions. This is what this project is addressing. Sammanfattning  After each Swedish winter, the costs due to winter maintenance and long-term road repairs are extensive and, unfortunately, current repair techniques provide only a temporary solution until the next freezing period. Given the extensiveness of the Swedish winters season, to ensure the economic, societal and environmental prosperity of the Swedish infrastructure, it is therefore of paramount importance to improve the resistance of the current and future road network against these winter conditions and develop effective tools and methods to assist in winter maintenance actions. The main objective and novelty of the FROSTSAFE project is to reduce the vulnerability of the Swedish road infrastructure against winter damage, by developing new methods and technologies for: (i) improvement winter maintenance; (ii) optimization of asphalt mixtures at multiple scales and (iii) prediction of in-time damage development. The expected results of this project are i) an operational, fully calibrated computational model; ii) design guides for the optimum choice of asphalt mixture components and test protocols to maximize the overall asphalt mixture frost damage resistance and minimize in-time degradation; iii) design guides for pavement monitoring and maintenance during winter months and the prediction of maintenance intervals; and iv) the experimental tools and knowledge to increase safety and drive comfort on the road network. Förväntat resultat  The FROSTSAFE deliverables will be: - for the pavement R&D industry : an operational, fully calibrated computational model for frost damage evaluation of asphalt mixtures which can be used for improved pavement design. - for the pavement construction industry : design guides for the optimum choice of asphalt mixture components and test protocols to maximize the overall asphalt mixture frost damage resistance and minimize in-time degradation. - for the Swedish road authorities : design guides for pavement monitoring and maintenance during winter months taking into account the in-time degradation of pavement frost damage resistance as a function of asphalt mixture characteristics, loading characteristics and pavement geometry, and the prediction of maintenance intervals. - for the community at large: the experimental tools and knowledge which are developed in the FROSTSAFE project will contribute to an increased safety and drive comfort on the road network. The project will hereby build on tools, test procedures and material knowledge which has been previously developed in other projects (financed from Trafikverket, Vetenskapsrådet and industry sponsored). To ensure the efficiency of the project, first and extensive literature review will be performed, which will result in a mapping of the existing state-of-the-art tools and principles that are (inter)nationally available and connect these to the aims and scope of this project. Plan för resultatspridning och implementering  - During the project each year a one-day meeting will be organized will all the partners of the project as well as guest speakers, to discuss the project. - Mid-way the project (after two years) and at the end of the project (after 4 years) a workshop will be organized in which more speakers are invited to discuss on the topic and where the results of the project are presented and discussed. - From the project, it is expected that 3-5 conference contributions to local and international conferences as well as 4-6 scientific publications in peer-reviewed journals will be written; - The project will be using the Road2Science Virtual World to further spread the results of the project; - The participants of the project are expected to be active participants in various academy-industry meeting events. Tidsramar  The project is expected to start in 2015, as soon as a suitable PhD student has been appointed. For this, the position will be advertised via the KTH recruitment pages and all applicants will be considered. If good candidate apply, the project can expect after summer. If the process –for some reason takes longer- the project is expected to start in fall 2015. The project will last for 4 years, so: - Start: late summer / fall 2015 - Closure: late summer / fall 2019