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Copenhagen, Denmark

Kidmose J.,Geological Survey of Denmark | Refsgaard J.C.,Geological Survey of Denmark | Troldborg L.,Geological Survey of Denmark | Seaby L.P.,Geological Survey of Denmark | Escriva M.M.,Danish Road Directorate
Hydrology and Earth System Sciences

This paper presents a first attempt to estimate future groundwater levels by applying extreme value statistics on predictions from a hydrological model. Climate scenarios for the future period, 2081-2100, are represented by projections from nine combinations of three global climate models and six regional climate models, and downscaled (including bias correction) with two different methods. An integrated surface water/groundwater model is forced with precipitation, temperature, and potential evapotranspiration from the 18 models and downscaling combinations. Extreme value analyses are performed on the hydraulic head changes from a control period (1991-2010) to the future period for the 18 combinations. Hydraulic heads for return periods of 21, 50 and 100 yr (T21-100) are estimated. Three uncertainty sources are evaluated: climate models, downscaling and extreme value statistics. Of these sources, extreme value statistics dominates for return periods higher than 50 yr, whereas uncertainty from climate models and extreme value statistics are similar for lower return periods. Uncertainty from downscaling only contributes to around 10% of the uncertainty from the three sources. © 2013 Author(s). Source

Hansen J.S.,Roskilde University | Lemarchand C.A.,Roskilde University | Nielsen E.,Danish Road Directorate | Dyre J.C.,Roskilde University | Schroder T.,Roskilde University
Journal of Chemical Physics

We propose a four-component united-atom molecular model of bitumen. The model includes realistic chemical constituents and introduces a coarse graining level that suppresses the highest frequency modes. Molecular dynamics simulations of the model are carried out using graphic-processor-units based software in time spans in order of microseconds, which enables the study of slow relaxation processes characterizing bitumen. This paper also presents results of the model dynamics as expressed through the mean-square displacement, the stress autocorrelation function, and rotational relaxation. The diffusivity of the individual molecules changes little as a function of temperature and reveals distinct dynamical time scales. Different time scales are also observed for the rotational relaxation. The stress autocorrelation function features a slow non-exponential decay for all temperatures studied. From the stress autocorrelation function, the shear viscosity and shear modulus are evaluated, showing a viscous response at frequencies below 100 MHz. The model predictions of viscosity and diffusivities are compared to experimental data, giving reasonable agreement. The model shows that the asphaltene, resin, and resinous oil tend to form nano-aggregates. The characteristic dynamical relaxation time of these aggregates is larger than that of the homogeneously distributed parts of the system, leading to strong dynamical heterogeneity. © 2013 American Institute of Physics. Source

Jansen J.M.,Danish Road Directorate
Bridge Maintenance, Safety, Management and Life-Cycle Optimization - Proceedings of the 5th International Conference on Bridge Maintenance, Safety and Management

Management of the road infrastructure asset encompasses a holistic management of all road infrastructure elements in the corridor, both capital works on pavements, structures and installations and routine maintenance works on areas and equipment. Asset management is not only to provide best practice maintenance, but also to deliver perceived outcomes in relation to stakeholders' value. To do this, much more knowledge than just engineering has to be incorporated in the process of road infrastructure asset management. This paper presents the complexity of asset management for modern road administrations and gives examples of how this process has been approached. © 2010 Taylor & Francis Group, London. Source

Agency: Cordis | Branch: FP7 | Program: CSA-ERA-Plus | Phase: SST.2013.1-3. | Award Amount: 9.03M | Year: 2014

Europe needs to redefine its transport system for the 21st century. Performance and cost-efficiency of the system need to be improved to meet future challenges. This means there is an urgent need for effective innovation for all components of the system; including vehicles, infrastructure, logistics etc. Transport ministries across Europe are facing ever tougher challenges to cope with the need to accommodate increased traffic growth, minimise congestion, maintain services in face of increasing climate change effects, as well as deliver on environmental and societal objectives. This is the time when innovation for road infrastructure is an absolute imperative to reduce costs without compromising on quality. To deliver this objective on a transnational basis, the ERA-NET Plus action on infrastructure innovation Infravation - is initiated enabling national bodies to take on tasks collectively that otherwise could not be taken forward. This scheme will allow for bringing together the efforts of member states, EC and industry. The Infravation call will be launched in March 2014 and is expected to be supported through the FP7 2013 Work Programme. Infravation comprises 11 European countries, one region and the EC. For the first time the USA will contribute funding to an ERA-NET Plus. The total pot available for R&D funding amounts to 9,025 M. The topics addressed reflect the needs of researchers/industry, road infrastructure owners and operators and EC for joint research on road infrastructure. Infravation will pave the way to a new quality of transnational research funding cooperation by applying a real common pot that merges national and EC top-up funding into one funding pot This approach allows for a coordinated, common governance structure for R&D projects funded, enabling the best expertise to be used, regardless of nationality and thereby minimising programme management and allow the maximum use of resources for transnational research cooperation.

Agency: Cordis | Branch: FP7 | Program: CP | Phase: ENV.2011.3.1.9-1 | Award Amount: 4.98M | Year: 2012

The goal of Light2CAT is to develop new, highly efficient visible-light-activated titanium dioxide for inclusion in concretes to be used in structures across the whole of Europe to improve ambient air quality independent, for the first time, of local climate conditions. The need to improve air quality in European Countries has been identified as a major requirement to be achieved within the next decade in the effort to control climate change, a key Europe 2020 strategy, and to improve human health. Despite vigorous efforts to reduce levels of hazardous substances in the air, targets remain a challenge. One of the most valid sustainable technologies explored so far is photocatalytic concrete. This technology is proven to reduce the amount of hazardous air pollutants up to 80 % . It also imparts self-cleaning properties to built structures which has a secondary effect of reducing harsh cleaning chemicals entering the water systems. However, the titanium oxide based photocatalytic building materials are activated by ultraviolet light so, to date, such environmental benefits are limited to countries with a high incidence of sunlight. The concept of this project is to extend the use of photocatalytic concretes to the whole of Europe by developing materials that can also be activated by visible light . The aim is to remove climate and seasonal considerations from the use of the materials and, through higher conversion efficiencies of the catalytic components, to reduce production costs facilitating further take up of the technology within existing markets. The results of the project are initially focused on use within the transport infrastructure where the greatest impact is expected. The consortium is well conceived to achieve the results, comprising research centres leading research in these materials and industry partners including SMEs able to develop, demonstrate and market the new materials in the sector.

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