During a research project in the years 2012 to 2014, 90 bitumens of different grades from eight different refineries were analyzed thoroughly. The results provide a detailed and extensive overview about the rheological properties and chemical compositions of the bitumens used in road construction in Germany. The results, measured with the Dynamic Shear Rheometer (DSR) at cold temperatures, correspond well with the stiffness and the relaxation-properties, measured with the Bending Beam Rheometer. The stiffness at 25 °C corresponds well with the needle penetration at the same temperature. The improvements of the DSR-analysis at this temperature are a better differentiation of harder bitumens and the additional information, given by the phase angle. The properties at high service temperatures could also be analyzed more precisely and more performance related with the DSR. Unmodified bitumens show a precise correlation between the stiffness and the softening point ring and ball. Due to the fact that the determination of the softening point of modified bitumens often causes problems, an equiviscosity temperature for the shear modulus of 15 kPa is a suitable substitute for the softening point ring and ball. For the very reason that the viscosity at high temperatures is a suitable criterion for the asphalt's production, processing and compac-tion, the DSR gives an analysis of the bitumen's whole service-temperature-range. The results of the research project show that all currently used test methods can be replaced equivalently by the DSR. Furthermore, the DSR provides characteristic values for a more precise bitumen analysis, particularly for modified bitumens.
<p>The Offshore Wind Energy Act (Windenergie-auf-See-Gesetz - WindSeeG) legally requires annual tender procedures for sites in the North Sea in the Exclusive Economic Zone of Germany for the construction of wind turbines. The Federal Maritime and Hydrographic Agency (Bundesamt f&#252;r Seeschifffahrt und Hydrographie - BSH) conducts so called preliminary investigation of sites (PIS), pursuant to &#167;10 WindSeeG. These include investigations of the wind conditions at the site, to give the interested firms information for calculating a bid. The preliminary investigation of the wind conditions is conducted together with the German Weather Service (Deutscher Wetterdienst) and is based on three elements: a measurement campaign at the site for one year, an evaluation of reanalysis data by the German Weather Service, and a report which brings together all available information about the wind conditions. These reports are published together with the measurement and model data and the results of all other preliminary investigations via the PIS-Data Hub https://pinta.bsh.de as part of the tendering process.</p><p>The sites that are dedicated for the construction of wind turbines are defined in the Site Development Plan (Fl&#228;chenentwicklungsplan), together with the year of the intended tendering process. The first PIS have been successfully completed for two sites in the southeastern North Sea and for one site in the Baltic Sea in March 2021. In the years 2022 and 2023, a call for tender for sites N-3.5, N-3.6 and N-7.2 will be published. These sites are located in the southwestern part of the German Exclusive Economic Zone in the North Sea. At or near these sites, meteorological measurements have been conducted, using a floating lidar which was installed on a buoy (site N-7.2) as well as scanning lidars installed on the transition pieces of wind turbines (N-3.5, N-3.6). These measurements resulted in time series of vertical profiles of wind direction and speed, covering one year each, and giving information about the wind conditions at the sites at relevant heights of future wind turbines. In addition, temperature, relative humidity, air pressure, and sea surface temperature were measured.</p>
Bitumen is a crucial building material in road construction, which is exposed to continuously higher stresses due to higher traffic loads and changing climatic conditions. Therefore, various additives are increasingly being added to the bitumen complicating the characterisation of the bituminous binder, especially concerning the reuse of reclaimed asphalt. Therefore, this work aimed to demonstrate that the combination of Fourier transform infrared (FTIR) spectroscopy with attenuated total reflexion (ATR) technique and multivariate evaluation is a very well-suited method to reliable identify and quantify additives in bituminous binders. For this purpose, various unmodified and modified binders, directly and extracted from laboratory and reclaimed asphalts, were investigated with FTIR-ATR spectroscopy. The determined spectra, pre-processed by standard normal variate (SNV) transformation and the determination of the 1st derivation, were evaluated using factor analysis (FA), linear discriminant analysis (LDA) and partial least square regression (PLSR). With this multivariate evaluation, first, a significant model with a very high hit rate of over 90% was developed allowing for the identification of styrene-butadiene copolymers (SBC), ethylene-copolymer bitumen (ECB) and different waxes (e.g. amide and Fischer-Tropsch wax) even if the additives do not show any additional peaks or the samples are multi-modified. Second, a quantification of the content is possible for SBC, ECB, and amide wax with a mean error of RMSE ≤ 0.4 wt% and a coefficient of determination of R2 > 90%. Based on these results, FTIR identification and quantification of additives in bituminous binders is a very promising method with a great potential.
<p>F&#252;r die erfolgreiche Durchf&#252;hrung der Energiewende ist die Errichtung von Offshore-Windparks in der Ausschlie&#223;lichen Wirtschaftszone (AWZ) Deutschlands ein wichtiger Baustein. Bisher wurden die Windparks in der Deutschen Bucht und in der Westlichen Ostsee durch die jeweiligen Betreiber geplant und die Planung beim Bundesamt f&#252;r Seeschifffahrt und Hydrographie (BSH) als zust&#228;ndiger Genehmigungsbeh&#246;rde gepr&#252;ft. Mit dem Inkrafttreten des WindSeeG ist ein Teil dieser Planungshoheit auf das BSH &#252;bergegangen: Nunmehr werden die Fl&#228;chen, die f&#252;r die Errichtung von Windparks geeignet sind, &#246;ffentlich ausgeschrieben, um den am besten geeigneten Betreiber zu ermitteln. Ma&#223;geblich ist die H&#246;he der beanspruchten staatlichen F&#246;rderung. Vor der Ausschreibung werden die Fl&#228;chen durch das BSH in Bezug auf Baugrund, Meeresumwelt sowie die vorhandenen Wind- und ozeanographischen Verh&#228;ltnisse untersucht. Diese Untersuchungen dienen neben der Entscheidung &#252;ber die Eignung der Fl&#228;che insbesondere auch der Gebotsberechnung durch die Bieter. Die erste Ausschreibungsrunde startet im M&#228;rz 2021 mit den Fl&#228;chen N-3.7, N-3.8 in der Nordsee und O-1.3 in der Ostsee.</p> <p>F&#252;r die Kalkulation des Ertrages durch die Bieter sind genaue Informationen &#252;ber die Windverh&#228;ltnisse entscheidend. Der DWD koordiniert dazu die Zusammenstellung verschiedener Datenquellen. Hierbei handelt es sich a) um die Messungen des Windprofils in H&#246;hen von etwa 30 m bis 100 m an den Forschungsplattformen in Nord- und Ostsee, FINO1 und FINO2, b) die durch externe Auftragnehmer im Auftrag des BSH durchgef&#252;hrten einj&#228;hrigen In-Situ-LiDAR-Messungen auf den Fl&#228;chen N-3.7 und N-3.8 sowie c) Auswertungen der Daten der Reanalysen COSMO REA6 und ERA5 durch den DWD. Diese Daten sind Grundlage f&#252;r die Erstellung zusammenfassender Gesamtberichte &#252;ber die Windverh&#228;ltnisse in den 3 Fl&#228;chen nach Stand von Wissenschaft und Technik.</p> <p>Der Vortrag gibt einen &#220;berblick &#252;ber die rechtlichen Rahmenbedingungen, die f&#252;r das Ausschreibungsjahr 2021 durchgef&#252;hrten Untersuchungen sowie einen Ausblick auf die k&#252;nftigen Herausforderungen.</p> <p>&#160;</p>
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