TY - CONF A1 - Stengel, Dominik A1 - Mehdianpour, Milad A1 - Clobes, M. ED - Bucher, C. T1 - Böenbeanspruchung von Freileitungsseilen - Naturmessungen, Windkanalversuche und numerische Simulationen N2 - Im Rahmen eines Forschungsprojekts zur Tragverhaltensstudie von Freileitungsseilen unter Böenbeanspruchung soll durch die Kombination von Naturmessungen, Windkanalversuchen und numerischen Simulationen versucht werden, das mechanische Verhalten von Freileitungsseilen und turbulenter Windbeanspruchung genauer abzubilden. Die Unsicherheiten bei der Modellierung dieses Zufallsprozesses sollen durch Windkanalversuche und Naturmessungen auf ein Minimum reduziert werden. Im vorliegenden Beitrag werden Ergebnisse von Simulationen mit den Beobachtungen aus den Naturmessungen verglichen und bewertet. Ziel des Forschungsvorhabens ist die Bewertung der aktuellen Bemessungsvorschriften für die Berücksichtigung von Wind auf Leiterseile. T2 - 13. Dreiländertagung D-A-CH 2013 CY - Wien, Austria DA - 10.10.2013 PY - 2013 SN - 3-928909-12-6 N1 - Serientitel: WtG-Berichte – Series title: WtG-Berichte VL - 13 SP - 37 EP - 47 AN - OPUS4-29316 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mehdianpour, Milad A1 - Stengel, Dominik T1 - Wind measurements along a high-voltage overhead transmission line in Northern Germany - Appraisal of results N2 - The paper focuses on a unique project of wind measurements along a high voltage Overhead transmission line. For reliable information on the horizontal distribution of the wind flow, 13 positions along two spans of an overhead electrical line of about 400 m length each are selected for wind velocity measurements. Simultaneously, the structural response is measured at the towers. Preliminary analyses aim at the appraisal of results what is important for the upcoming system identification. It is shown that system identification of long span transmission lines exposed to gusty wind is possible by derivation of a so called joint acceptance function which describes the admittance from wind velocity to the system’s response. T2 - EACWE 2013 - 6th European-African conference on wind engineering CY - Cambridge, UK DA - 07.07.2013 PY - 2013 SP - 1 EP - 8 (Paper 13) AN - OPUS4-28863 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Mehdianpour, Milad A1 - Clobes, M. T1 - Böenbeanspruchung von Freileitungsseilen - Naturmessungen, Windkanalversuche und numerische Simulationen T2 - 13. Dreiländertagung der WtG CY - Vienna, Austria DA - 2013-10-10 PY - 2013 AN - OPUS4-29623 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Mehdianpour, Milad ED - Gomes, J.F.S. ED - Meguid, S.A. T1 - Wind measurements along a high-voltage overhead transmission line in northern Germany N2 - The paper focuses on a recently launched project of wind measurements along a high voltage overhead transmission line. For reliable information on the actual horizontal distribution of the wind flow, 13 positions along two spans of an overhead electrical line of about 400 m length each are selected for wind measurements. Simultaneously, the structural response is measured at the towers. Preliminary analyses aim at the system identification of long span transmission lines exposed to gusty wind by derivation of a so called joint acceptance function which describes the admittance from wind velocity to the system's response. It can be shown that measured structural response can accurately be described using a statistical model which accounts for the irregularity of the wind as well as the structure’s behaviour. T2 - IRF 2013 - 4th International conference on integrity, reliability and failure CY - Funchal, Portugal DA - 23.06.2013 KW - Overhead transmission lines KW - Wind loading KW - Field measurements KW - Monitoring PY - 2013 SN - 978-972-8826-28-4 IS - Paper 3920 SP - 1 EP - 9 AN - OPUS4-28846 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Mehdianpour, Milad T1 - Wind measurements along a high-voltage overhead transmission line in Northern Germany T2 - 4th International Conference on Integrity, Reliability & Failure CY - Funchal, Portugal DA - 2013-06-23 PY - 2013 AN - OPUS4-29178 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Stengel, Dominik T1 - Naturmessungen und numerische Simulationen zur Untersuchung von Freileitungsseilen im natürlichen Wind N2 - Für Tragmasten von Freileitungen ist meist die Windeinwirkung bemessungsrelevant. Mit den großen Spannweiten der Hochspannungsebene trägt dabei die Windeinwirkung auf die Leiterseile einen maßgebenden Anteil zur Gesamtbeanspruchung dieser Tragstrukturen bei. Daher ist es offensichtlich, dass das Tragverhalten der Freileitungsseile eine wichtige Rolle für die zuverlässige Bemessung bei Neubauten oder der Bewertung der Zuverlässigkeit des Bestands spielt. Hierfür sind insbesondere die Extremwindereignisse, das sog. 50-Jahres-Windereignis von Bedeutung. Bei diesen hohen Windgeschwindigkeiten treten vor allem windinduzierte Schwingungen der Leiterseile auf. Die für die Bemessung herangezogenen Konzepte basieren meist auf Übertragungsmodellen im Frequenzbereich. Diese setzen eine Linearisierung um den Arbeitspunkt der mittleren Verschiebung voraus, welche nur unter der Annahme von kleinen Schwingungsamplituden gerechtfertigt ist. Dabei kommt der Systemdämpfung eine wichtige Rolle zu. Zwar ist die Strukturdämpfung für Litzenseile vernachlässigbar gering, doch unter Windeinwirkung kann die aerodynamische Dämpfung aufgrund der Relativgeschwindigkeit zwischen Anströmung und Struktur zu beachtlicher Größe anwachsen. Die Beschreibung des Tragverhaltens im Zeitbereich erlaubt es, das nichtlineare Verhalten der Kraftübertragung, sowie der großen Verformungen zu berücksichtigen. Damit lassen sich für die Bemessung relevante Parameter identifizieren und notwendige Annahmen zur Windeinwirkung, sowie zur quasistationären Kraftübertragung überprüfen. Gerade das Verhalten von Freileitungsseilen unter Extremwindereignissen, auf das es zu Extrapolieren gilt, kann so im Rahmen der getroffenen Annahmen simuliert werden. Anhand von Naturmessungen werden die Übertragungsmodelle, sowie das Zeitbereichsmodell bei eher moderaten Windgeschwindigkeiten überprüft. Durch die Verteilung von Windsensoren entlang der Leitung kann die für die Belastung der Leiterseile maßgebende laterale Windverteilung annähernd erfasst werden. Bestehende Annahmen hierzu werden überprüft und erweitert. Für die Zeitbereichsrechnungen wird eine Methode zur Windfeldgenerierung dahingehend erweitert, dass die Windereignisse auch adäquat im Zeitbereich wiedergegeben werden können. Mit dem Ziel, eine zuverlässigere Bemessung von Freileitungen unter turbulenter Windbeanspruchung zu erreichen, werden sog. Spannweitenfaktoren abgeleitet und auf andere Leitungskonfigurationen übertragen, die die Mechanik der Leiterseile sowie die maßgebenden Eigenschaften der Windeinwirkung beinhalten. N2 - Regarding suspension towers of overhead transmission lines, wind is the most critical load case in design. Wind action on conductors significantly contributes to the overall loading of those supporting structures in case of wide spanning cables used in high voltage level. Hence it is inherent that loadbearing characteristic of conductor cables plays an important role for reliable design of new constructions or evaluation of reliability level of existing structures. Therefor extreme wind situations, a so-called 50-years wind event is of particular interest. Under such high wind velocities, mainly wind induced vibrations of conductor cables occur. Concepts employed for design purpose are mostly based on admittance functions in frequency domain. This implies linearization around the operating position of mean deflection, which is only valid for the assumption of small vibration amplitudes. Herein damping of the system becomes important. Structural damping of stranded wires is indeed negligible low, but in case of wind action aerodynamic damping increases significantly due to the relative velocity between acting wind flow and structure. The description of loadbearing characteristics in time domain allows considering nonlinear behavior of force admittance as well of large displacements. Relevant parameters for design can thereby be identified and necessary assumptions on wind action as well as quasi-steady force admittance can be validated. Just by that the behavior of overhead transmission line cables under extreme wind events which need to be extrapolated, can be simulated by means of the assumptions made. Models of admittance as well as a model in time domain are validated by means of field measurements at rather moderate wind speeds. Distributing wind sensors along an overhead transmission line, the lateral distribution of wind which is decisive for the loading of conductor cables can be captured. Existing assumptions for this are validated and extended. For calculations in time domain, a method for generation of a wind field will be extended in order to reproduce wind events adequately also in time domain. Aiming at a reliable design of overhead transmission lines under turbulent wind, so-called span reduction factors are derived and converted to other transmission line configurations which include the mechanics of overhead line conductors as well as the predominant characteristics of wind loading. T3 - BAM Dissertationsreihe - 150 KW - Hochspannungsleiter KW - Windbelastung KW - Naturmessungen KW - Windkanalversuche KW - Finite Element Methode PY - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-372171 SN - 978-3-9817853-7-1 SN - 1613-4249 VL - 150 SP - I EP - 126 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-37217 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stengel, Dominik A1 - Mehdianpour, Milad T1 - Finite element modelling of electrical overhead line cables under turbulent wind load N2 - This paper presents a finite element model of an overhead transmission line using so called cable elements which allow reproducing the cable's nonlinear characteristics accurately employing only a few elements. Aerodynamic damping is considered in the equation of motion by taking into account the relative velocity between the flow of the wind and the moving structure. The wind flow itself is simulated by wave superposition making necessary assumptions on the lateral correlation between the wind velocities along the cable length. As result from the simulation, the following conclusions can be drawn. The first natural frequency of generally used wide spanning cables lies well below 1 Hz where also most of the energy content of the wind excitation is to be expected. Aerodynamic damping is significant for the moving cables holding very low structural damping which leads to a suppression of resonant amplification. This is particularly of interest regarding the support reaction which is dominated by the mean value and the so called background response. The latter is mostly influenced by the randomness of the wind flow, especially lateral to the main wind direction. KW - Nonlinear Finite Element Formulations KW - Nonlinear Equation of Motion KW - Turbulent Wind Excitation PY - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-304567 SN - 2314-6494 SN - 2356-766X VL - 2014 IS - Article ID 421587 SP - 1 EP - 8 PB - Hindawi Publ. CY - New York, NY ; Cairo AN - OPUS4-30456 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Mehdianpour, Milad T1 - MOSYTRAF-Monitoringsystem zur Tragverhaltensstudie von Freileitungsseilen unter Böenbeanspruchung T2 - 12. Fachtagung Baustatik-Baupraxis CY - Munich, Germany DA - 2014-02-24 PY - 2014 AN - OPUS4-30269 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Mehdianpour, Milad A1 - Clobes, M. A1 - Thiele, K. ED - Cunha, A. ED - Caetano, E. ED - Ribeiro, P. ED - Müller, G. T1 - Numerical simulation of an overhead power line section under wind excitation using wind tunnel test results and in-situ measured data N2 - Overhead transmission lines are very sensitive structures in regards to wind action. The cables, spanning over a few hundred meters contribute in particular to the overall action on the suspension towers. These slender structures incorporate both structural nonlinearities from the large deformation of the cables and aerodynamic nonlinearities which need to be accounted for when it is to estimate the system response to strong wind events. In this work, a finite element procedure is presented to model an existing power line section using nonlinear cable elements. The wind force is assumed quasi-steady with force coefficients determined in wind tunnel test on a conductor section. Further, aerodynamic damping is incorporated by considering the relative velocity between cable nodes and oncoming wind flow. The results are compared with on-site measurements of the cable’s support reaction. The results show a significant effect of damping since almost no resonant amplification is visible both in observation and simulation. In addition, wind tunnel tests approved aerodynamic damping to be large for the system of sagging cables, but nonlinear in its nature. It is concluded, that the dynamic response of overhead transmission line cables has to be modeled with care, considering all sources of nonlinearities. That is of particular interest in case of random excitation such as wind because the peak response depends on the probability distribution of the system's response. T2 - EURODYN 2014 - 9th International conference on structural dynamics CY - Porto, Portugal DA - 2014-06-30 KW - Overhead transmission lines KW - Cable dynamics KW - Aerodynamic damping KW - Wind tunnel KW - In-situ measurements PY - 2014 SN - 978-972-752-165-4 SN - 2311-9020 SP - Paper MS07, 1 EP - 6 AN - OPUS4-30993 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Clobes, M. A1 - Mehdianpour, Milad ED - Schlünzen, K.H. T1 - Overhead transmission line cables under wind gust loading - measurements and numerical simulations N2 - Overhead transmission lines with conductor cables spanning over a few hundred meters are highly sensitive to the action of wind. Particularly wind acting on the cables signifies a major load on the suspension towers. In order to identify critical loading parameters and the load-response mechanism of those structures, measurements are carried out along a high voltage overhead transmission line capturing the acting wind field as well as the structural response of the cables. A finite element model of the structure is built and used to simulate the system's response. A method is presented which allows generating a complete wind field for all the model’s nodes incorporating measured wind velocities and estimated parameters of the acting wind. The full scale measurements of both action and reaction will be compared to the numerical results. T2 - CWE 2014 - 6th International symposium on computational wind engineering CY - Hamburg, Germany DA - 2014-06-08 PY - 2014 SP - Article 0158_0016, 1 EP - 8 AN - OPUS4-30860 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Clobes, M. A1 - Mehdianpour, Milad T1 - Overhead transmission line cables under wind gust loading - measurements and numerical simulations T2 - CWE2014 6. Internatinal Symposium on Computational Wind Engineering CY - Hamburg, Germany DA - 2014-06-08 PY - 2014 AN - OPUS4-30849 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Mehdianpour, Milad A1 - Clobes, M. A1 - Thiele, K. T1 - Numerical simulation of an overhead power line section under wind excitation using wind tunnel test results and in-situ measured data T2 - EURODYN 2014 IX International Conference on Structural Dynamics CY - Oporto, Portugal DA - 2014-06-30 PY - 2014 AN - OPUS4-31054 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik T1 - Sequential tests of HTLS conductors N2 - Mechanical and electrical sequential tests of high temperature low sag (HTLS) conductors and accessories to be performed at the BAM laboratories are presented. T2 - BestPaths Subtask 6.1 HTLS Workshop & Meeting CY - Berlin, Germany DA - 01.06.2016 KW - High temperature low sag (HTLS) conductors KW - Mechanical tests PY - 2016 AN - OPUS4-38438 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Peil, U. ED - Ruscheweyh, H. ED - Krafczyk, M. T1 - Zur Bemessung von Freileitungsgittermasten auf Wind auf Leiterseile nach der Freileitungsnorm DIN EN 50341-3-4: 2011 N2 - Der folgende Beitrag befasst sich mit der analytischen Herleitung eines sog. Spannweitenfaktors zur Berücksichtigung der Korrelation der Windeinwirkung auf weitgespannte Freileitungsseile. Insbesondere zur Abschätzung der Windlast auf Maste trägt dieser Lastfall maßgebend zur Bemessung bei. Mithilfe von Naturmessungen und Simulationen werden zugrunde gelegte Annahmen überprüft und validiert. Die Ergebnisse werden schließlich anhand der einschlägigen Regelwerke verglichen und bewertet. N2 - The following paper addresses an analytical derivation of a so-called span reduction factor considering the correlation of wind acting on wide spanning overhead transmission line conductors. This load case contributes significantly to the estimation of the total wind load on the towers in particular. With the aid of full scale measurements as well as simulations, the underlying assumptions are reviewed and validated. Finally the results are compared and evaluated with applicable standards. T2 - 14. Dreiländertagung D-A-CH 2015 - Windingenieurtechnik - Vom Bauteilnachweis bis zum Stadtklima CY - Braunschweig, Germany DA - 05.10.2015 PY - 2015 SN - 3-928909-13-4 N1 - Serientitel: WtG-Berichte – Series title: WtG-Berichte IS - 14 SP - 109 EP - 119 AN - OPUS4-34543 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Thiele, K. A1 - Clobes, M. A1 - Mehdianpour, Milad T1 - Aerodynamic damping of nonlinear movement of conductor cables in laminar and turbulent wind flow N2 - It is widely accepted that aerodynamic damping is a decisive parameter influencing the dynamic response of overhead transmission line conductors in turbulent wind flow. But anyway, methods of how to account for the effects of aerodynamic damping differ significantly and so might do the results. In this work, the source of aerodynamic damping shall be revised leading to the well-known formulation for a linear pendulum being the result of the relative velocity between the structure and wind flow. Based on wind tunnel tests and validated by simulations, the differences to a pendulum movement of a sagging cable are shown. The reasons for that deviation are the large deflections, resulting in a movement non parallel to the acting wind flow. For some analysis, in particular those in frequency domain, it is practically not possible to incorporate aerodynamic damping implicitly by fluid structure interaction. If the dynamic movement can be linearized at a working point of the mean deflection, a modification to the linear approach is suggested. This approach is validated by simulation with a finite element model of an existing overhead transmission line, calibrated with onsite measurements for wind velocities at lower levels. Further accent is put on the different possibilities to incorporate aerodynamic damping in time step analysis, such as Rayleigh damping or modal damping. The differences between both approaches are emphasized and modal damping is shown to be the most adequate representation of aerodynamic damping. T2 - ICWE14 - 14th International conference on wind engineering CY - Porto Alegre, Brazil DA - 21.06.2015 KW - Aerodynamic damping KW - Conductor cables KW - Overhead transmission lines KW - Wind tunnel experiments KW - Nonlinear finite element simulation PY - 2015 SN - 978-85-66094-07-7 SP - 1 EP - 9 AN - OPUS4-33612 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik T1 - Bericht zum Zwischenstand des Forschungsvorhabens MOSYTRAF N2 - Präsentation des Zwischenstands des Forschungsvorhabens MOSYTRAF mit erreichten Zielen, Einordnung der Ergebnisse und Ausblick auf eine weitere Laufzeit vor den Projektpartnern und -förderern. T2 - MOSYTRAF Projektgruppentreffen zum Zwischenstand CY - Berlin, Germany DA - 24.11.2016 KW - MOSYTRAF KW - Hochspannungs-Freileitungen KW - Dauerüberwachung PY - 2016 AN - OPUS4-38490 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Clobes, M. A1 - Thiele, K. T1 - Investigation on the dynamic behavior of an OHL conductor bundle with light and heavy ice accretion N2 - Under a variety of possible cable vibrations which overhead line conductors can suffer, galloping identifies by large amplitudes at rather low frequencies. Changes of the cross-section as by ice-accretion provide the basis for such vibrations through an aerodynamic instability of drag and lift responses under wind excitation. Two different types of light and heavy ice bodies attached to a quad bundle conductor are analysed in wind tunnel tests. The results of aerodynamic drag and lift coefficients are investigated by means of a finite element model under turbulent wind excitation. It was found that instability can be well simulated for the heavy ice accretion but not for the case of lightly iced conductors. T2 - 8th International Colloquium on Bluff Body Aerodynamics and Applications CY - Boston, MA, USA DA - 07.06.2016 KW - wind turbulence KW - overhead transmission line KW - bundle conductors KW - ice accretion KW - dynamic behaviour PY - 2016 SP - Paper 116, 1 EP - Paper 116, 8 AN - OPUS4-36554 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Clobes, M. A1 - Thiele, K. T1 - Investigation on the dynamic behavior of an OHL conductor bundle with light and heavy ice accretion N2 - Under a variety of possible cable vibrations which overhead line conductors can suffer, galloping identifies by large amplitudes at rather low frequencies. Changes of the cross-section as by ice-accretion provide the basis for such vibrations through an aerodynamic instability of drag and lift responses under wind excitation. Two different types of light and heavy ice bodies attached to a quad bundle conductor are analysed in wind tunnel tests. The results of aerodynamic drag and lift coefficients are investigated by means of a finite element model under turbulent wind excitation. It was found that instability can be well simulated for the heavy ice accretion but not for the case of lightly iced conductors. T2 - 8th International Colloquium on Bluff Body Aerodynamics and Applications CY - Boston, MA, USA DA - 07.06.2016 KW - ice accretion KW - overhead transmission line KW - bundle conductors KW - dynamic behaviour KW - wind turbulence PY - 2016 AN - OPUS4-36556 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stengel, Dominik A1 - Mehdianpour, Milad T1 - Windbeanspruchung von Hochspannungs-Freileitungsseilen in Naturmessungen, Zeitbereichssimulation und Norm T1 - Wind load of high voltage overhead transmission line con ductors in field measurements, time domain simulations and standard N2 - Die Beanspruchung von Freileitungen erfolgt hauptsächlich durch Naturlasten. Dabei spielt für die bemessungsbestimmenden Lastfälle häufig der Wind eine entscheidende Rolle. Die Leiter, die mehrere hundert Meter weit spannen, tragen einen wesentlichen Anteil zur Gesamtbeanspruchung von Tragmasten bei, die wiederum Eigengewicht und Windlasten der Leiter zwischen zwei Abspannmasten abtragen. Wenn die Reaktion der Seile auf Starkwindereignisse abgeschätzt werden soll, müssen sowohl geometrische Nichtlinearitäten durch die großen Verformungen wie auch aerodynamische Nichtlinearitäten berücksichtigt werden. Insbesondere für die Anwendung und Berücksichtigung in Bemessungsvorschriften werden hierfür Vereinfachungen vorgenommen. In diesem Beitrag wird eine umfassende Untersuchung vorgestellt, über Naturmessungen, FEM-Simulationen kombiniert mit Windkanalversuchen und generierten Windzeitreihen. Ziel ist es, existierende Bemessungsvorschriften im Hinblick auf die Abschätzung der Beanspruchung aus Wind auf Leiter zu validieren. Hierbei sind insbesondere die Turbulenzannahmen und das dynamische Verhalten von weitgespannten Leitern wichtig, um die Extremschnittgrößen zu beschreiben. Mithilfe von so genannten Spannweitenfaktoren sollen die relevanten Parameter, wie Spannweite und Windturbulenz, bei der Beanspruchungsabschätzung berücksichtigt werden. N2 - The loading of overhead lines comprises of natural actions mainly. Wind loading signifies an important load case in the design of overhead transmission line structures. Conductors spanning often several hundreds of meters contribute significantly to the overall loading of suspension towers. Those towers are often designed as a mass product to support the dead and wind load of the conductors between two dead end towers. Estimating the reaction of the conductors to strong winds, both geometric nonlinearities because of the large deformations as well as aerodynamic nonlinearities need to be considered. Particularly for design procedures, those effects should be simplified. This paper presents a thorough investigation comprising field measurements along an existing overhead line, simulations with FEM combined with wind tunnel tests and generated wind fields. It is the aim of the study to validate the actual design procedure regarding loading of wind acting on conductors. Most important herein in order to describe the extreme response are assumptions on turbulence distribution and dynamic behavior of wide spanning overhead line conductors. According to usual design procedure, by means of so called span reduction factors, relevant parameters such as span length and wind turbulence can be considered. KW - Langzeitmessung KW - FEM-Simulation KW - Dynamik PY - 2017 U6 - https://doi.org/10.1002/stab. 201710437 SN - 1437-1049 VL - 86 IS - 1 SP - 45 EP - 53 PB - Ernst & Sohn CY - Berlin AN - OPUS4-38899 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Thiele, K. A1 - Clobes, M. A1 - Mehdianpour, Milad T1 - Aerodynamic damping of nonlinear movement of conductor cables in laminar and turbulent wind flow T2 - 14th International Conference on Wind Engineering CY - Porto Alegre, Brasil DA - 2015-06-21 PY - 2015 AN - OPUS4-33549 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Peil, Udo T1 - Zur Bemessung von Freileitungsgittermasten auf Wind auf Leiterseile nach der Freileitungsnorm DIN EN 50341-3-4: 2011 T2 - 14. Dreiländertagung der WtG CY - Braunschweig, Deutschland DA - 2015-10-05 PY - 2015 AN - OPUS4-34393 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mehdianpour, Milad A1 - Stengel, Dominik ED - Bletzinger, K.-U. ED - Fisch, R. ED - Gebbeken, N. T1 - MOSYTRAF - Monitoringsystem zur Tragverhaltensstudie von Freileitungen unter Böenbeanspruchung N2 - Im Rahmen des Forschungsvorhabens MOSYTRAF (Monitoringsystem zur Tragverhaltensstudie von Freileitungen unter Böenbeanspruchung) werden seit Ende 2011 kontinuierlich Windgeschwindigkeiten entlang eines insgesamt 800 m langen Freileitungsabschnitts gemessen. Gleichzeitig wird die resultierende Windkraft aus Wind auf Leiterseile an den Isolatoren erfasst. Dadurch soll der Zusammenhang zwischen Einwirkung und Bauwerksreaktion möglichst zuverlässig ermittelt werden. Dabei ist besonderes Augenmerk auf die kurzzeitigen Windgeschwindigkeitsspitzen, die Böen gerichtet. Diese erfassen anders als die konstante mittlere Windgeschwindigkeit, nicht die gesamte Länge des Freileitungsabschnitts, sondern nur einen eingeschränkten Bereich. Aus diesem Grund erfolgen die Windmessungen an insgesamt 13 Stellen entlang des Abschnitts und geben ein fein aufgelöstes Bild des Windfeldes. In dem Beitrag werden Messergebnisse beispielhaft präsentiert und einige Plausibilitätskontrollen vorgestellt, da dies einen unerlässlichen Schritt bei Naturmessungen darstellt. Ausgehend von einem Übersichtsdiagramm der bisherigen Messergebnisse wird die Aufgabenstellung und die Zielsetzung der Messkampagne erörtert. T2 - Fachtagung Baustatik - Baupraxis 12 CY - München, Germany DA - 24.02.2014 PY - 2014 SN - 978-3-00-041256-1 SP - 159 EP - 167 PB - A.A. Balkema Publishers AN - OPUS4-30290 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Schneider, Ronald A1 - Baeßler, Matthias T1 - Lebensdauerverlängerung von Offshore-Windenergieanlagen im Betrieb N2 - Vorschlag zur möglichen Lebensdauerverlängerung einzelner Bauteile einer im Betrieb befindlichen Offshore-Windenergieanlage durch Beschreibung der Versagenswahrscheinlichkeiten Beschreibung der Versagenswahrscheinlichkeit durch geeignete Schädigungsmodelle Aktualisierung der Versagenswahrscheinlichkeiten aufgrund von Inspektionsergebnissen und möglichen Reparaturen auf Basis der Bayes‘schen Entscheidungstheorie Quantifizierte Bewertung von Inspektionsmethoden und Reparaturmaßnamen im Hinblick auf die Zuverlässigkeit der Bauteile Grundlage für Entscheidungen für Inspektionen und Reparaturen T2 - Offshoretage CY - Heiligendamm, Germany DA - 15.03.2017 KW - Risikobasierte Maßnahmenplanung KW - Kostenoptimierung KW - Offshore Windenergie PY - 2017 AN - OPUS4-39448 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Bardl, Richard A1 - Kühnel, C. A1 - Großmann, S. A1 - Kiewitt, W. T1 - Accelerated electrical and mechanical ageing tests of high temperature low sag (HTLS) conductors N2 - As part of the Best Paths project, work package 6 of the DEMO #4 combines the R&D tasks for repowering of transmission overhead line corridors. The aim of the presented research work is the electrical and mechanical investigation of high temperature low sag conductors (HTLS) and their respective accessories. In contrast to the conventional ACSR (aluminum conductor steel reinforced) conductors, new material combinations of HTLS technologies result in a better sagging behavior combined with an operation at higher temperatures. Because of missing operational experience, the ageing behavior of HTLS conductor technologies shall be analyzed regarding the operating parameters such as electrical, thermal and mechanical load. T2 - ICOLIM Conference 2017 CY - Strasbourg, France DA - 25.04.2017 KW - High temperature low sag conductors KW - Accelerated ageing KW - Long-term loading PY - 2017 SN - 978-1-5090-5132-8 SP - 1 EP - 6 AN - OPUS4-40040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stengel, Dominik A1 - Thiele, K. T1 - Measurements of downburst wind loading acting on an overhead transmission line in Northern Germany N2 - Along an overhead transmission line in Northern Germany, a unique instrumentation of anemometers and force measurements is installed. Details of this test line with wind measurements along a horizontal axis are given. A recent event of a presumable downburst wind event is analyzed by means of available data and precedent works on thunderstorm analysis. The measured response of the conductors at the suspension tower is investigated and compared with time domain simulation of a finite element model. T2 - X International Conference on Structural Dynamics, EURODYN 2017 CY - Rome, Italy DA - 10.09.2017 KW - Non-synoptic wind event KW - Downburst KW - Overhead transmission line KW - Finite element method PY - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-421239 SN - 1877-7058 VL - 199 IS - Supplement C SP - 3152 EP - 3157 PB - Elsevier AN - OPUS4-42123 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Auersch, Lutz A1 - Stengel, Dominik T1 - Measurements of downburst wind loading acting on an overhead transmission line in northern Germany N2 - Along an overhead transmission line in Northern Germany, a unique instrumentation of anemometers and force measurements is installed. Details of this test line with wind measurements along a horizontal axis are given. A recent event of a presumable downburst wind event is analyzed by means of available data and precedent works on thunderstorm analysis. The measured response of the conductors at the suspension tower is investigated and compared with time domain simulation of a finite element model. T2 - EURODYN 2017 CY - Rome, Italy DA - 10.09.2017 KW - Downburst KW - Overhead transmission line KW - Finite element method KW - Non-synoptic wind event PY - 2017 AN - OPUS4-42491 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kühnel, C. A1 - Bardl, Richard A1 - Stengel, Dominik A1 - Kiewitt, W. A1 - Grossmann, S. T1 - Investigations on the mechanical and electrical behaviour of HTLS conductors by accelerated ageing tests N2 - To cope with future requirements, the transfer capacities of distribution systems as well as of transmission systems in Europe need to be increased. Therefore repowering of existing overhead lines with high temperature low sag con-ductors (HTLS) can be one interesting possibility. Because of limited experiences with that technology, current re-search of TU Dresden, the Federal Institute for Materials Research and Testing (BAM) and 50Hertz Transmission GmbH investigates the ageing behaviour of several differ-ent HTLS technologies in a consortium with other Euro-pean partners. In this context, accelerated ageing tests of conductors and its corresponding fittings with combined mechanical and electrical loads are done. To evaluate the changes due to ageing, several mechanical tests of the con-ductors are carried out and the contact behaviour of the fittings is analysed. T2 - CIRED Conference CY - Glasgow, Scotland, UK DA - 12.06.2017 KW - HTLS KW - High temperature low sag KW - Resistance KW - Self-damping PY - 2017 SP - Paper 0200, 1 EP - 5 AN - OPUS4-40869 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stengel, Dominik A1 - Kießling, F. A1 - Mehdianpour, Milad A1 - Özbey, U.-Y. A1 - Pohl, H. T1 - Windlasten auf Freileitungen - Windmessungen an einer 380-kV-Freileitung N2 - Windeinwirkungen auf Freileitungen wurden in der Vergangenheit meist an exponierten Standorten bestimmt. In einem Langzeitversuch wurden seit 2012 an einer mit moderner Messtechnik ausgerüsteten 380-kV-Leitung der 50 Hertz Transmission GmbH, die im nicht besonders exponierten Gelände verläuft und somit den Leitungen im Netz entspricht, die Windgeschwindigkeiten entlang der Leiter und deren Auswirkungen auf die Stützpunkte gemessen. Die Messungen und die begleitenden Auswertungen bestätigen die heute verwendeten normativen Vorgaben für die Windwirkung auf die Leiter von Freileitungen, soweit dies in der relativ kurzen Zeit von fünf Jahren möglich ist. KW - Wind KW - Freileitungen PY - 2017 VL - 2017 IS - 9 SP - 68 EP - 72 PB - EW Medien und Kongresse GmbH CY - Frankfurt am Main AN - OPUS4-42119 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stengel, Dominik A1 - Thiele, K. A1 - Clobes, M. A1 - Mehdianpour, Milad T1 - Aerodynamic damping of nonlinear movement of conductor cables in wind tunnel tests, numerical simulations and full scale measurements N2 - Aerodynamic damping is a decisive parameter influencing the dynamic response of overhead transmission line conductors. Methods of how to account for the effects of aerodynamic damping differ significantly and so might do the results. In this work, the source of aerodynamic damping being the result of the relative velocity between the structure and wind flow will be revised. Based on wind tunnel tests and validated by simulations, the differences of linear movement compared to a pendulum movement of a sagging cable are shown. The reasons for that Deviation are the large deflections, resulting in a movement non-parallel to the acting wind flow. For analysis in frequency domain, it is not possible to incorporate aerodynamic damping implicitly by fluid structure interaction. If the dynamic movement can be linearized at a working point of the mean deflection, a modification to the linear approach is suggested. This approach is validated by simulation with a finite element model of an existing overhead transmission line, calibrated with full scale measurements. Aerodynamic damping is incorporated in time step analysis by Rayleigh damping and modal damping. The differences between both approaches are emphasized and modal damping is shown to be the most adequate. KW - Aerodynamic damping KW - Overhead transmission lines KW - Conductors KW - Nonlinearities PY - 2017 U6 - https://doi.org/10.1016/j.jweia.2017.07.002 SN - 0167-6105 SN - 1872-8197 VL - 169 SP - 47 EP - 53 PB - Elsevier AN - OPUS4-41028 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik T1 - Grundlagen der stahlbaulichen Bemessung – Stabilität N2 - In dieser Blockveranstaltung lernen die Studierenden die Grundlagen der stahlbaulichen Bemessung zum Thema Stabilität. Inhalt ist eine kurze Einführung in die Problematik des Stabilitätsversagens. Danach wird eingegangen auf die Grundlagen des Bemessungsverfahrens nach EC 3, gefolgt von einer Nachweisführung anhand eines Beispiels. T2 - Blockseminar an der Zhejiang University of Science & Technology CY - Hangzhou, China DA - 09.06.2017 KW - Stahlbau KW - Stabilität PY - 2017 AN - OPUS4-40612 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -