TY - CHAP A1 - Pasternak, Hartmut A1 - Chwastek, Agnieszka T1 - Fatique assessment of non-load carrying fillet welds after seams repair and treatment procedures T2 - 7th European Conference on Steel and Composite Structures, Eurosteel, Neapel, 2014 Y1 - 2014 SN - 978-92-9147-121-8 SP - 263 EP - 264 PB - ECCS European Convention for Constructional Steelwork CY - Brussels ER - TY - CHAP A1 - Pasternak, Hartmut A1 - Bartholomé, Susanne Elisabeth A1 - Bulkowski, Marcin T1 - Retrofitting of Cracks in Steel Construction - using CFRP Laminates T2 - 7th European Conference on Steel and Composite Structures, Eurosteel, Neapel 2014 Y1 - 2014 SN - 978-92-9147-121-8 PB - ECCS European Convention for Constructional Steelwork CY - Brussels ER - TY - GEN A1 - Pasternak, Hartmut A1 - Sahellie, Samer T1 - Epoxy- and acrylic-bonded joints for strengthening lightweight steel girders T2 - Stahlbau Y1 - 2015 SN - 0038-9145 SN - 1437-1049 VL - 84 IS - 8 SP - 577 EP - 583 ER - TY - GEN A1 - Pasternak, Hartmut A1 - Sahellie, Samer T1 - Expectancy of the lifetime of bonded steel joints due to long-term shear loading T2 - Archives of Civil and Mechanical Engineering Y1 - 2015 U6 - https://doi.org/10.1016/j.acme.2015.05.004 SN - 1644-9665 VL - 15 IS - 4 SP - 1061 EP - 1069 ER - TY - GEN A1 - Pasternak, Hartmut A1 - Ciupack, Yvonne A1 - Schiel, Manuel A1 - Ince, Erdeniz T1 - Adhesive bonded joints in steel structures T2 - Steel Construction Y1 - 2014 SN - 1867-0539 VL - 7 IS - 3 SP - 173 EP - 182 ER - TY - CHAP A1 - Pasternak, Hartmut A1 - Krausche, Thomas A1 - Launert, Benjamin T1 - Welding of thick steel plates under site conditions T2 - 7th European Conference on Steel and Composite Structures, Eurosteel, Neapel, 2014 Y1 - 2014 SN - 978-92-9147-121-8 SP - 109 EP - 110 PB - ECCS European Convention for Constructional Steelwork CY - Brussels ER - TY - CHAP A1 - Pasternak, Hartmut A1 - Ciupack, Yvonne A1 - Schiel, Manuel A1 - Ince, Erdeniz T1 - Adhesive bonded joints in steel structures T2 - 7th European Conference on Steel and Composite Structures, Eurosteel, Neapel, 2014 Y1 - 2014 SN - 978-92-9147-121-8 SP - 265 EP - 266 PB - ECCS European Convention for Constructional Steelwork CY - Brussels ER - TY - CHAP A1 - Pasternak, Hartmut A1 - Stojković, Nenad T1 - Fatique of adhesively bonded structural elements - residuel strenght models T2 - 14th International Scientific Conference VSU 2014, Sofia, 2014, Vol. 2 Y1 - 2014 SP - 34 EP - 39 PB - VSU ER - TY - CHAP A1 - Pasternak, Hartmut A1 - Sahellie, Samer T1 - Concentration of the normal stresses in the adherends of adhesively-bonded double lap steel joints due to reducing the width of the bonded area T2 - 14th International Scientific Conference VSU 2014, Sofia, 2014, vol. 2 Y1 - 2014 SP - 197 EP - 202 PB - Univ. of Structural Engineering and Architecture CY - Sofia ER - TY - GEN A1 - Schlaich, Mike A1 - Bleicher, Achim A1 - Pasternak, Hartmut T1 - Der Porsche Pavillon in Monocoque-Bauweise T2 - Bauingenieur Y1 - 2014 SN - 1436-4867 SN - 0005-6650 VL - 89 IS - 1 SP - 1 EP - 10 ER - TY - GEN A1 - Pasternak, Hartmut A1 - Krausche, Thomas A1 - Niemann, M. T1 - Umbau eines Schulgebäudes der Heinrich-Nordhoff-Gesamtschule in Wolfsburg T2 - Bauingenieur Y1 - 2014 SN - 1436-4867 SN - 0005-6650 VL - 89 IS - 4 SP - 182 EP - 185 ER - TY - GEN A1 - Feldmann, Markus A1 - Geßler, Achim A1 - Ummenhofer, Thomas A1 - Götz, Frank A1 - Bartholomé, Susanne Elisabeth A1 - Pasternak, Hartmut T1 - Zum Kleben von CFK-Lamellen im Stahlbau T2 - BTU Stahlbau-Symposium 2014, Cottbus, 2014 Y1 - 2014 SP - 83 EP - 90 PB - BTU CY - Cottbus [u.a.] ER - TY - CHAP A1 - Pasternak, Hartmut A1 - Moradi, Milad A1 - Krausche, Thomas T1 - Reconstruction of a school building in Wolfsburg, Germany T2 - Tubular Structures XV, Proceedings of the 15th International Symposium on Tubular Structures, Rio de Janeiro, Brazil, 27-29 May 2015 Y1 - 2015 SN - 978-1-138-02837-1 SP - 31 EP - 35 PB - CRC Press CY - Hoboken ER - TY - GEN A1 - Pasternak, Hartmut A1 - Launert, Benjamin A1 - Krausche, Thomas T1 - Welding of girders with thick plates — Fabrication, measurement and simulation T2 - Journal of Constructional Steel Research N2 - This article presents experimental and numerical results of the fabrication of welded plate girders under workshop conditions. Main concerns are the prediction of imperfections with the aid of simulation tools and/or simplified engineering models. Their impact on the component design is evaluated in a case study. Special focus is put on the effect of residual welding stress. For this, different simplified distributions are compared with results from welding simulation. The findings confirm the thesis that present recommendations on the implementation of weld-induced imperfections must be rated conservative. This suggests that it is necessary to establish new models. Guidance on future problems in this context will be given. KW - Welded plate girders; Welding simulation; Residual welding stress; Load capacity Y1 - 2015 UR - http://www.sciencedirect.com/science/article/pii/S0143974X15300833 U6 - https://doi.org/10.1016/j.jcsr.2015.08.037 SN - 0143-974X VL - Vol. 115 SP - 407 EP - 416 ER - TY - CHAP A1 - Pasternak, Hartmut A1 - Krausche, Thomas A1 - Launert, Benjamin T1 - Welded construction site joints in bridges T2 - Steel Bridges: Innovation & New Challenges, 8th International Symposium on Steel Bridges, Istanbul, 2015 N2 - In large steel construction, as in steel bridges, construction site welds are made under difficult conditions such as low temperatures and wind. The comprehensive study will show not only test results from the analysis in the climate chamber (large scale test) with low temperatures (-20°C, -10°C) as well as numerical calculations with the help of welding simulation and non-linear structural analysis. Deflections and temperature are given and compared with traditional engineering models and advises for future problems are presented. For bridge girders with I cross sections, welded thick plates are used and there joining need to be considered precisely. Effect from welding, such as deflections and residual stresses, will have an outcome on the performed component. For welding of thick plates multi-layer welding is used. The edges need to be cut before welding. The preparation process needs to be considered as well as actual joining to have an economic performance. As joint geometry the Z-joint was chosen and investigated. Results from testing as well as from the welding simulation will be shown and compared. Thereby an engineering model will be consulted to evaluate the results. To evaluate the impact of the welding process a FEM load capacity calculation was performed and will be compared with test without imperfections from the joining process. KW - Welded Joints, Welding Simulation, Engineering Models, Load Capacity Calculation Y1 - 2015 SN - 978-605-65900-2-3 SP - 315 EP - 320 PB - Turkish Constructional Steelwork Association (TUCSA) CY - Istanbul, Turkey ER - TY - BOOK A1 - Nitschke-Pagel, Thomas A1 - Klassen, Jakob A1 - Pasternak, Hartmut A1 - Launert, Benjamin A1 - Krausche, Thomas T1 - P 858 - Schweißen dicker Bleche unter Baustellenbedingungen – Beurteilung des Einflusses auf das Tragverhalten von Montagestößen N2 - Beim Aufbau großer Stahlstrukturen im Brücken- oder Stahlhochbau wird heute vermehrt auf modulare Fabrikfertigung gesetzt. Ein Fügen dieser Module auf der Baustelle zu einer Gesamtstruktur ist aber weiterhin notwendig. Als Fügeverfahren wird hier häufig das MAG-Mehrlagenschweißen eingesetzt. Gerade an dicken Blechen stellen Baustellenschweißungen nicht nur besondere Anforderungen an den ausführenden Betrieb, die Bauleitung und Bauüberwachung, sondern auch an den Konstrukteur. Wichtig für den Konstrukteur ist die Kenntnis der sich durch Schweißungen einstellenden Schrumpfung der Bauteile, der auftretenden Verzüge und Eigenspannungen. Gerade bei Baustellenschweißungen müssen diese Aspekte in der Konstruktionsphase der Einzelkomponenten mit berücksichtigt werden, um die erforderlichen Toleranzen bei der Montage einzuhalten. Eine genaue Kenntnis der durch Schweißungen verursachten Phänomene ist in den Konstruktions- und Montagebetrieben oft nur aus mehrjährigen Erfahrungen vorhanden. Ein grundlegendes, vollständiges Bild der Abläufe beim Schweißen auf der Baustelle, das es ermöglicht, dieses Wissen auf neue Konstruktionen zu übertragen, fehlt bisher. Insbesondere für die immer öfter im Brücken- und Stahlhochbau eingesetzten höherfesten Feinkornbaustähle (z.B. S460) ist die Kenntnis des Verhaltens bei Baustellenschweißungen notwendig. Hier setzt der Forschungsantrag an. Mit Hilfe der Schweißsimulation können die Auswirkungen von Schweißnähten, wie die Entstehung von Verzügen und Eigenspannungen am Bauteil, global dargestellt werden. Eine anschließende Struktursimulationen (Festigkeits- und Steifigkeitsberechnungen) mit aus der Schweißsimulation integrierten Ergebnissen bildet die Basis für ergänzende Untersuchungen. Montagestöße sind außerdem durch Verschmutzung und Witterung negativ beeinflusst. Die Montage kann beispielsweise bei niedrigen Temperaturen unterhalb des Gefrierpunkts durchgeführt werden müssen. Diese Situation wurde in einer Klimakammer simuliert und die Auswirkungen der Umgebungstemperatur bei der Montage auf das Tragverhalten der Verbindung untersucht. Für die im Rahmen des Vorhabens untersuchten Fälle ist kein Einfluss variierender Umgebungstemperaturen bis -10 °C auf die resultierenden Schweißeigenspannungen festzustellen. Der Vergleich von Verzug und Eigenspannung gegenüber normativ vorgegeben Toleranzwerten sowie vereinfachten Ingenieurmodellen für die Approximation des Eigenspannungsverlaufs zeigt große Defizite. Bei realitätsnaher Implementierung der Eigenspannungen in die Traglastberechnung können z.T. große Reserven im Rahmen der nichtlinearen Traglastberechnung ausgenutzt werden. KW - Bauteilversuche, Stahlbau, Stabilität, Normen Y1 - 2015 UR - https://www.stahldaten.de/de/shop/fosta-berichte/werkstoffverhalten/p-858/ SN - 978-3-942541-69-5 PB - Verlag und Vertriebsgesellschaft mbH CY - Düsseldorf ER - TY - GEN A1 - Pasternak, Hartmut A1 - Krausche, Thomas T1 - The Porsche Pavilion in the Autostadt Wolfsburg, Germany T2 - Procedia Engineering KW - monocoque KW - stainless steel KW - innovative building design KW - construction welding KW - light steel construction Y1 - 2013 U6 - https://doi.org/10.1016/j.proeng.2013.04.010 SN - 1877-7058 IS - 57 SP - 63 EP - 69 ER - TY - GEN A1 - Bartholomé, Susanne Elisabeth A1 - Pasternak, Hartmut A1 - Feldmann, Markus A1 - Geßler, Achim A1 - Ummenhofer, Thomas A1 - Götz, Frank T1 - Verstärkung von Stahlkonstruktionen durch geklebte CFK-Lamellen T2 - 20. DASt-Forschungskolloquium in Essen, 08./09. März 2016 Y1 - 2016 SN - 978-3-941687-19-6 SP - 89 EP - 94 PB - Frehner Consulting CY - Füssen ER - TY - CHAP A1 - Bartholomé, Susanne Elisabeth A1 - Pasternak, Hartmut A1 - Feldmann, Markus A1 - Geßler, Achim A1 - Ummenhofer, Thomas A1 - Götz, Frank T1 - Kleben von CFK-Lamellen im Stahlbau T2 - DVS Congress 2015, Große Schweißtechnische Tagung, Nürnberg Y1 - 2015 SN - 978-3-945023-46-4 SP - 927 EP - 932 PB - DVS Media CY - Düsseldorf ER - TY - CHAP A1 - Bartholomé, Susanne Elisabeth A1 - Pasternak, Hartmut A1 - Feldmann, Markus A1 - Geßler, Achim A1 - Ummenhofer, Thomas T1 - Systematische Untersuchung zur Verstärkung von Stahlkonstruktionen mit kohlefaserverstärkten Kunststoffen (CFK) T2 - Tagungsband, 16. Kolloquium Gemeinsame Forschung in der Klebtechnik, Köln, März 2016 Y1 - 2016 SP - 45 EP - 47 PB - DECHEMA, Gesellschaft für Chemische Technik und Biotechnologie e.V. CY - Frankfurt am Main ER - TY - CHAP A1 - Bartholomé, Susanne Elisabeth A1 - Pasternak, Hartmut A1 - Bulkowski, Marcin T1 - Risssanierung von dynamisch beanspruchten Stahlbauteilen mit kohlenfaserverstärkten Kunststoffen (CFK-Lamellen) T2 - DVS Congress 2015, Große Schweißtechnische Tagung, Nürnberg Y1 - 2015 SN - 978-3-945023-46-4 SP - 597 EP - 602 PB - DVS Media CY - Düsseldorf ER - TY - GEN A1 - Pasternak, Hartmut A1 - Kubieniec, Gabriel T1 - Implementation of longitudinal welding stresses into structural calculation of steel structures T2 - JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT Y1 - 2016 U6 - https://doi.org/10.3846/13923730.2014.994029 SN - 1392-3730 SN - 1822-3605 VL - 22 IS - 1 SP - 47 EP - 55 ER - TY - GEN A1 - Pasternak, Hartmut A1 - Sahellie, Samer T1 - Conversion factors of the temperature effect on the shear strength of adhesively bonded steel joints T2 - Journal of civil engineering and management Y1 - 2016 U6 - https://doi.org/10.3846/13923730.2015.1068848 SN - 1392-3730 VL - 22 IS - 5 SP - 666 EP - 672 ER - TY - CHAP A1 - Launert, Benjamin A1 - Rhode, Michael A1 - Pasternak, Hartmut A1 - Kannengießer, Thomas ED - Dubina, Dan ED - Ungureanu, Viorel T1 - Welding residual stresses in high-strength steel. Experimental results T2 - The International Colloquium on Stability and Ductility of Steel Structures N2 - This article presents the latest results of an ongoing national research project on improved models for the prediction of welding residual stresses of thick-plated welded I-girders. The experimental program is presented and the importance of different influencing factors on the residual stresses is discussed in detail. All results are compared for mild (S355J2+N) and high strength (S690QL) steel. Finally, conclusions for further works are drawn. KW - Residual stresses, High-strength steel, Welded sections, Measurement Y1 - 2016 SN - 978-92-9147-133-1 SP - 517 EP - 524 PB - Ernst & Sohn ET - 2016 edition ER - TY - CHAP A1 - Ciupack, Yvonne A1 - Pasternak, Hartmut A1 - Ledecky, Lukas A1 - Mette, Christoph A1 - Stammen, Elisabeth A1 - Dilger, Klaus ED - Virdi, Kuldeep ED - Tenhunen, Lauri T1 - Adhesive bonded steel structures under cyclic loading T2 - Proceedings of the METNET Seminar 2015 in Budapest, 2015 Y1 - 2015 SN - 978-951-784-762-9 SN - 978-951-784-763-6 SP - 90 EP - 101 PB - HAMK University of Applied Sciences CY - Hämeenlinna ER - TY - CHAP A1 - Stojković, Nenad A1 - Ledecky, Lukas A1 - Ciupack, Yvonne A1 - Pasternak, Hartmut A1 - Mette, Christoph A1 - Stammen, Elisabeth A1 - Dilger, Klaus T1 - Tensile strength of adhesively bonded façade joints T2 - The Sixth International Conference Civil Engineering - Science & Practice, Montenegro, 2016 Y1 - 2016 SN - 978-86-82707-30-1 SP - 273 EP - 280 ER - TY - CHAP A1 - Jäger, A. A1 - Pasternak, Hartmut T1 - Grundlegende Studien zum Beulverhalten von engringversteiften Kreiszylinderschalen unter Axialdruck T2 - Offen im Denken, 20. DASt-Forschungskolloquium in Essen, 08./09. März 2016 Y1 - 2016 SN - 978-3-941687-19-6 SP - 38 EP - 42 PB - Deutscher Ausschuß für Stahlbau DASt CY - Düsseldorf ER - TY - CHAP A1 - Ledecky, Lukas A1 - Stojković, Nenad A1 - Ciupack, Yvonne A1 - Pasternak, Hartmut A1 - Mette, Christoph A1 - Fischer, Vitali A1 - Stammen, Elisabeth A1 - Dilger, Klaus T1 - Service loading and fatigue behavior of adhesively bonded steel-steel façade joints T2 - 16th International Scientific Conference VSU 2016, Sofia, 2016, vol. 1 Y1 - 2016 SP - 187 EP - 192 PB - VSU CY - Sofia ER - TY - CHAP A1 - Pasternak, Hartmut A1 - Launert, Benjamin A1 - Kannengießer, Thomas A1 - Rhode, Michael ED - Zingoni, Alphose T1 - Residual stresses and imperfections in welded high-strength I-shape members T2 - Insights and Innovations in Structural Engineering, Mechanics and Computation, Proceedings of the Sixth International Conference on Structural Engineering, Mechanics and Computation, Cape Town, South Africa, 5-7 September 2016 N2 - This article addresses the imperfections caused by the weld assembly in I-shape sections made of two structural steel grades. Load influencing imperfections are assumed as deviations from the ideal shape (e.g. bending distortion) and longitudinal residual stresses. The quality of a numerically aided design of components exposed to either compression and/or bending is significantly affected, depending on these parameters [1]. The Eurocode provides robust simplified models. As a result, the Ultimate Limit State (ULS) is approached on a conservative basis. The following investigations are aimed at providing further guidance on these values in component-like specimens. The long term goal is an improved understanding of the load-bearing capacity of such sections. As a first step in this process, the experimental and corresponding numerical studies are presented. Y1 - 2016 UR - https://www.crcpress.com/Insights-and-Innovations-in-Structural-Engineering-Mechanics-and-Computation/Zingoni/p/book/9781138029279 SN - 978-1-138-02927-9 SP - 403 EP - 404 PB - Taylor & Francis CY - London ER - TY - CHAP A1 - Pasternak, Hartmut A1 - Krausche, Thomas T1 - Details of the steel assembly of a membrane-cladded double ­ curved cable net roof T2 - ICCAEE 2016 Kuala Lumpur/Malaysia, 2nd International Congress on Technology - Engineering & Science Y1 - 2016 PB - University of Malaysia CY - Pahang ER - TY - GEN A1 - Bartholomé, Susanne Elisabeth A1 - Pasternak, Hartmut A1 - Feldmann, Markus A1 - Geßler, Achim A1 - Ummenhofer, Thomas A1 - Ruff, Daniel T1 - Alternative Verstärkungsmaßnahme im Stahlbau mit aufgeklebten unidirektionalen CFK-Lamellen T2 - Schweißen und Schneiden Y1 - 2016 SN - 0036-7184 VL - 68 IS - 8 SP - 490 EP - 499 ER - TY - GEN A1 - Jäger, Andreas A1 - Pasternak, Hartmut T1 - Studien zum Beulverhalten von eng ringversteiften Kreiszylinderschalen unter Axialdruck T2 - Bauingenieur Y1 - 2016 SN - 0005-6650 VL - 91 IS - 10 SP - 401 EP - 409 ER - TY - GEN A1 - Bartholomé, Susanne Elisabeth A1 - Pasternak, Hartmut A1 - Feldmann, Markus A1 - Geßler, Achim A1 - Ummenhofer, Thomas A1 - Ruff, Daniel T1 - Geklebte CFK-Lamellen verstärken Stahlbauteile T2 - Adhäsion KW - Stahlbau KW - Verstärkung KW - CFK-Lamelle Y1 - 2016 UR - http://link.springer.com/article/10.1007/s35145-016-0039-6 SN - 1619-1919 SN - 2192-8681 VL - 60 IS - 9 SP - 42 EP - 49 ER - TY - GEN A1 - Bartholomé, Susanne Elisabeth A1 - Pasternak, Hartmut T1 - Träger mit schlanken, wabenförmig strukturierten Stegen - Versuch und Simulation T2 - Stahlbau Y1 - 2016 U6 - https://doi.org/10.1002/stab.201610423 SN - 1437-1049 SN - 0038-9145 VL - 85 IS - 11 SP - 724 EP - 732 ER - TY - CHAP A1 - Launert, Benjamin A1 - Rhode, Michael A1 - Kromm, Arne A1 - Pasternak, Hartmut A1 - Kannengießer, Thomas ED - Holden, Thomas M. ED - Muránsky, Ondrej ED - Edwards, Lyndon T1 - Residual Stress Influence on the Flexural Buckling of Welded I-Girders T2 - Residual Stresses 2016 – ICRS-10 N2 - The nonlinear analysis became a common tool to precisely assess the load-bearing behavior of steel beam and column members. The failure level is significantly influenced by different types of imperfections, among geometric also structural imperfections (residual stresses). Here are still gaps in the knowledge. Nowadays, 3-D welding simulation developed to a level where it could provide reliable estimation of weld-induced distortion and residual stresses. Nevertheless, modelling and computational effort are still in a less practicable range. In this study a simplified procedure to implement residual welding stresses in continuous large scale members is proposed and the influence on the ultimate limit state of slender members in compression is evaluated for two common structural steel grades. The results showed significant improvements in the utilization of load bearing capacity compared with simplified design methods. The comparatively general approach in this study offers potential for future optimization. KW - Stability Design KW - Finite Element Method KW - 2-D Welding Simulation KW - Inherent Strain KW - PDA Y1 - 2016 UR - http://www.mrforum.com/product/9781945291166/ SN - 978-1-94529116-6 U6 - https://doi.org/10.21741/9781945291173-19 SP - 109 EP - 114 PB - Materials Research Forum LLC CY - Millersville, PA ER - TY - CHAP A1 - Kromm, Arne A1 - Rhode, Michael A1 - Launert, Benjamin A1 - Dixneit, Jonny A1 - Kannengießer, Thomas A1 - Pasternak, Hartmut ED - Holden, Thomas M. ED - Muránsky, Ondrej ED - Edwards, Lyndon T1 - Combining Sectioning Method and X-Ray Diffraction for Evaluation of Residual Stresses in Welded High Strength Steel Components T2 - Residual Stresses 2016 - ICRS-10 N2 - Residual stresses and distortions in welded I-girders for steel construction are relevant when evaluating the stability of steel beams and column members. The application of high strength steels allows smaller wall thicknesses compared to conventional steels. Therefore, the risk of buckling has to be considered carefully. Due to the lack of knowledge concerning the residual stresses present after welding in high strength steel components conservative assumptions of their level and distribution is typically applied. In this study I-girders made of steels showing strengths of 355 MPa and 690 MPa were welded with varying heat input. Due to the dimension of the I-girders and the complex geometry the accessibility for residual stress measurement using X-ray diffraction was limited. Therefore, saw cutting accompanied by strain gauge measurement has been used to produce smaller sections appropriate to apply X-ray diffraction. The stress relaxation measured by strain gauges has been added to residual stresses determined by X-ray diffraction to obtain the original stress level and distribution before sectioning. The combination of both techniques can produce robust residual stress values. From practical point of view afford for strain gauge application can be limited to a number of measuring positions solely to record the global amount of stress relaxation. X-ray diffraction can be applied after sectioning to determine the residual stresses with sufficient spatial resolution. KW - Weld Residual Stress KW - Sectioning Method KW - X-Ray Diffraction Y1 - 2016 UR - http://www.mrforum.com/product/9781945291166/ SN - 978-1-94529116-6 U6 - https://doi.org/10.21741/9781945291173-28 SP - 163 EP - 168 PB - Materials Research Forum LLC CY - Millersville, PA ER - TY - GEN A1 - Launert, Benjamin A1 - Szczerba, Radosław A1 - Gajewski, Marcin A1 - Rhode, Michael A1 - Pasternak, Hartmut A1 - Giżejowski, Marian T1 - The buckling resistance of welded plate girders taking into account the influence of post-welding imperfections – Part 1: Parameter study T2 - Materials Testing N2 - Welding is the most important joining technique and offers the advantage of customizable plate thicknesses. On the other hand, welding causes residual stresses and deformations influencing the load carrying capacity. Their consideration in the design requires simple and fast models. Though welding simulation has contributed to accurately access to these values nowadays, their application to large components remains still in a less practicable range. Nevertheless, many studies emphasized the need to make corrections in recently available simplified models. Especially the influence of residual stresses seems somewhat overestimated in many cases if comparing conventional structural steel S355 and high-strength steel S690. In times of computer-aided design, an improved procedure to implement weld-inducted imperfections appears overdue. This will be presented in two parts. The first part illustrates the potential influence of post-welding imperfections exemplified for weak axis buckling in comparison with the general method in accordance with Eurocode 3. Residual stresses and initial crookedness were varied systematically in order to produce a scatter band of capacities. An approach to characterize the borders of these imperfections was undertaken before that. The excessive scattering of reduction factors for the load bearing capacity demonstrates the importance of these variables. Results were finally evaluated against advanced simulation models which will be further detailed in part two of this contribution. KW - Welded plate girders KW - stability KW - post-welding imperfections KW - residual stresses KW - parameter study Y1 - 2017 UR - http://www.hanser-elibrary.com/doi/abs/10.3139/120.110964 U6 - https://doi.org/10.3139/120.110964 SN - 0025-5300 VL - 59 IS - 1 SP - 47 EP - 56 ER - TY - GEN A1 - Launert, Benjamin A1 - Rhode, Michael A1 - Kromm, Arne A1 - Pasternak, Hartmut A1 - Kannengießer, Thomas T1 - Measurement and numerical modeling of residual stresses in welded HSLA component-like I-girders T2 - Welding in the World N2 - The present contribution shows the residual stress results obtained from experiments with the sectioning method in comparison to global (structural) welding simulation models on component-like (i.e., large scale) I-girders made of structural steel grades S355 and S690QL. Plates were welded by conventional gas metal arc welding using two different heat inputs. In addition, the base material was assumed to be approximately stress-free. Based on these results, conclusions and recommendations for the design of welded I-girders are drawn. KW - Residual Stresses KW - Microalloyed steels KW - Girders KW - MAG welding KW - Simulating Y1 - 2016 UR - http://rdcu.be/n6mU U6 - https://doi.org/10.1007/s40194-016-0413-x SN - 0043-2288 SN - 1878-6669 VL - 61 IS - 2 SP - 223 EP - 229 ER - TY - GEN A1 - Loebjinski, Maria A1 - Rug, Wolfgang A1 - Pasternak, Hartmut T1 - Zuverlässigkeitsbewertung von Holzbauteilen im Bestand T2 - Bauingenieur N2 - Die aktuellen Bemessungsnormen des Eurocodes beinhalten keine gesonderten Regelungen für bestehende Bauwerke. Dennoch sind diese aus verschiedenen Gründen spezifisch zu bemessen. Dazu gehören sowohl öko-nomische Gründe, als auch Anforderungen an die Erhaltung von historischen Konstruktionen. Dieser Beitrag fasst Grundlagen zur Zuverlässigkeitstheorie und zur Ermittlung von Teilsicherheitsbeiwerten zusammen, stellt den aktuellen Stand der Technik zu Normen und Standards der zuverlässigkeitstheoretischen Bemessung und zur Behandlung von Bestandsbauten in der Bemessung dar und zeigt mit vereinfachten Rechnungen das Opti-mierungspotential der Teilsicherheitsbeiwerte für historische Holzkonstruktionen auf. Y1 - 2017 SN - 0005-6650 VL - 92 IS - 2 SP - 65 EP - 73 ER - TY - CHAP A1 - Ciupack, Yvonne A1 - Pasternak, Hartmut ED - Virdi, Kuldeep ED - Tenhunen, Lauri T1 - Bonding Technology in Steel Structures, a Summary of Research Activities at Chair of Steel and Timber Structures T2 - Proceedings of the METNET Seminar 2016 in Castellon Y1 - 2016 SN - 978-951-784-784-1 SP - 19 EP - 30 CY - Hämeenlinna ER - TY - GEN A1 - Pasternak, Hartmut A1 - Launert, Benjamin A1 - Kannengießer, Thomas A1 - Rhode, Michael T1 - Advanced Residual Stress Assessment of Plate Girders Through Welding Simulation T2 - Procedia Engineering N2 - This article provides an impression on potentials in applying nowadays welding simulation tools in construction design. This is carried out exemplary on plate girders from two structural steel grades. The calculated residual stresses are compared with measurements by sectioning method. It has been repeatedly stated that present Eurocode models fail to approximate the residual stresses. Especially for high strength steel (HSS) only limited information is available on realistic occurring residual stresses in typical I-girders. The investigations are aimed to give further guidance on these values. A few proposals on advanced models are discussed. KW - Residual stresses KW - Plate girders KW - I-shape sections KW - High-strength steel KW - Welding simulation KW - Advanced models Y1 - 2017 U6 - https://doi.org/10.1016/j.proeng.2017.02.013 SN - 1877-7058 VL - 172 SP - 23 EP - 30 ER - TY - GEN A1 - Kemper, Frank A1 - Ledecky, Lukas A1 - Feldmann, Markus A1 - Pasternak, Hartmut A1 - Fischer, Vitali T1 - Zeitabhängige Windbeanspruchungen von geklebten Fassadenanschlüssen T2 - Bauingenieur N2 - Für die Bemessung lastabtragender Klebverbindungen im Fassadenbereich ist zu beachten, dass die Windbelastungen auf den Bauwerksoberflächen sowohl zeitlich als auch räumlich veränderlich sind. Während für übliche Fassadenanschlüsse eine Bemessung mit charakteristischen Extremwerten ausreichend ist, muss beim Einsatz von sowohl höhermoduligen (z.B. Acrylat) als auch niedrigmoduligen (z.B. Polyurethan) Klebstoffen, die beide ein zeit- und temperaturabhängiges Materialverhalten aufweisen, eine vollständige Beschreibung dieser zeitbezogenen Lasteinwirkungen erfolgen. Nur dadurch wird letztlich die erforderliche betriebsfeste Auslegung eines geklebten Fassadenanschlusses ermöglicht. Im vorliegenden Beitrag wird die Ermittlung von zeitbezogenen Lasteinwirkungen und die Berechnung der daraus resultierenden Beanspruchungs-Zeit-Funktionen infolge einer natürlichen Windeinwirkungen auf Basis von Windkanalversuchen und Windstatistik thematisiert. Anhand geeigneter Zählverfahren und unter Berücksichtigung von klebstoffspezifischen Materialeigenschaften wird exemplarisch aufgezeigt, inwiefern unterschiedliche Fassadenpositionen und Windeigenschaften für die Auslegung von geklebten Fassadenanschlüssen von Bedeutung sind. Y1 - 2017 UR - http://www.bauingenieur.de/bauing/currentarticle.php?data[article_id]=87197 SN - 1436-4867 SN - 0005-6650 VL - 92 IS - 3 SP - 115 EP - 122 ER - TY - CHAP A1 - Simon, Flaviu A1 - Moradi, Milad A1 - Hildebrand, Jörg A1 - Pasternak, Hartmut ED - Hildebrand, Jörg ED - Loose, Tobias ED - Reich, Michael T1 - The influence of the welding sequence on the load bearing capacity and stress distribution of square hollow section steel joints T2 - Simulationsforum 2016, Schweißen und Wärmebehandlung, Weimar, Tagungsband 08.-10. November 2016 N2 - The aim of this contribution is to investigate the influence of welding sequencing patterns on the load bearing capacity of a S355 steel square hollow section (SHS) T-Joint. The failure and the joint behavior under loading condition are analyzed. The FE-software SYSWELD v2014 is used for the thermo-mechanical simulation of the welding process. The type of welding process used is metal active gas (MAG) welding. A fillet weld with a throat thickness of 5 mm is performed. After the welding simulation, the results in terms of stresses and distortion are validated with the experimental data. Due to the geometrical characteristics of this type of joint, a compressive test is performed. A load is applied on the upper surface the vertical member (brace). The force-displacement behavior is plotted and discussed. The differences and influencing parameters are identified. The model is prepared for the subsequent sensitivity study which will be done in the software OptiSLang, which is developed by Dynardo GmbH. Y1 - 2016 UR - http://www.fws-ev.de/fileadmin/downloads/Tagungsband_Simulationsforum_2016-Schweissen_und_Waermebehandlung_web.pdf SN - 978-3-00-054805-5 SP - 176 EP - 187 PB - Verein zur Förderung der numerischen Analyse der Wärmebehandlungs- und Schweißprozesse e.V. CY - Weimar ER - TY - CHAP A1 - Shlychkova, Darita A1 - Pasternak, Hartmut T1 - Numerical analysis of lightweight structured sandwich beams made of steel T2 - 16th International Scientific Conference VSU 2016, Sofia, 2016, vol. 1 N2 - Using a special technology it is possible to produce thin "honeycomb" structured plates. Such plates have been used e.g. for the roof of the sport complex "Olimp" in Odessa. That roof gives an extraordinary impression. That is why the question: how do structured plates behave as beams with C-section under concentrated force in the middle of the upper flange? In an ongoing project, two of those structured plates were assembled in different ways trough point welding. "Sandwich" beams were modelled and calculated using the nonlinear finite elements. Using Abaqus software load deformation curves for each beam and local stability were analyzed. Those sandwich beams may be used in exhibition stand construction. KW - Lightweight constructions, structured steel plates, sandwich beam, modelling Y1 - 2016 SP - 318 EP - 323 PB - VSU CY - Sofia ER - TY - CHAP A1 - Ledecky, Lukas A1 - Ciupack, Yvonne A1 - Pasternak, Hartmut A1 - Fischer, Vitali A1 - Stammen, Elisabeth A1 - Dilger, Klaus T1 - Untersuchungen zum Tragverhalten und der Lebensdauer von Klebverbindungen im Stahlbau unter zyklischen Belastungen (LebKleb) T2 - 17. Kolloquium Gemeinsame Forschung in der Klebtechnik, Tagungsband, 14. - 15. Februar 2017 Y1 - 2017 SP - 37 EP - 38 PB - DECHEMA CY - Frankfurt am Main ER - TY - CHAP A1 - Ledecky, Lukas A1 - Ciupack, Yvonne A1 - Pasternak, Hartmut A1 - Mette, Christoph A1 - Stammen, Elisabeth A1 - Dilger, Klaus T1 - Untersuchungen zum Tragverhalten und der Lebensdauer von Klebverbindungen im Stahlbau unter zyklischen Belastungen (LebKleb) T2 - 16. Kolloquium Gemeinsame Forschung in der Klebtechnik, Köln, 2016 Y1 - 2016 SP - 39 EP - 41 PB - DECHEMA CY - Frankfurt am Main ER - TY - GEN A1 - Ciupack, Yvonne A1 - Pasternak, Hartmut A1 - Mette, Christoph A1 - Stammen, Elisabeth A1 - Dilger, Klaus T1 - Adhesive bonding in steel construction - Challenge and innovation T2 - Procedia Engineering Y1 - 2017 U6 - https://doi.org/10.1016/j.proeng.2017.02.048 SN - 1877-7058 N1 - Modern Building Materials, Structures and Techniques, MBMST 2016, Vilnius VL - 172 SP - 186 EP - 193 ER - TY - CHAP A1 - Li, Zheng A1 - Pasternak, Hartmut T1 - Development of a stochastic material model at constant stress distribution in steel construction T2 - 16th International Scientific Conference VSU 2016, Sofia, 2016, vol. 1 N2 - This paper briefly presents the results of theoretical and experimental investigations on the size effect in metal. The Chain of Bundle Model, which is based on a stochastic material model by Weibull and log-normal distribution, will be developed and the possibility to approximately determine the parameter ξ of the model is given. The tests were performed on specimens from the same steel with different sizes. According to the experiments, the relationship between the sizes of the specimens and the strength can be analyzed through probability- and reliability theory. The theoretical and experimental results show that if the volume increases hundredfold, the strength will be reduced to 90% ~ 95%. Therefore, the size effect plays an unnegligible role in steel construction. Y1 - 2016 SP - 193 EP - 198 PB - VSU CY - Sofia ER - TY - CHAP A1 - Pasternak, Hartmut A1 - Krausche, Thomas T1 - A special Construction Site: the Guyed Mast at Torfhaus in the Harz Mountains, Germany T2 - Risk and Safety Engineering, 12th International Conference, Kopaonik, 2017 Y1 - 2017 UR - http://www.rizik.vtsns.edu.rs/en/zbornici-radova/ SN - 978-86-6211-107-4 SP - 540 EP - 545 PB - The Higher Education Technical School of Professional Studies CY - Novi Sad ER - TY - GEN A1 - Linke, Gunter A1 - Rug, Wolfgang A1 - Pasternak, Hartmut T1 - Festigkeitssortierung von Bauholz in historischen Gebäuden - Bericht zum Stand der Technik T2 - Bauingenieur Y1 - 2017 VL - 92 IS - 5 SP - 229 EP - 236 ER - TY - GEN A1 - Stojković, Nenad A1 - Folić, Radomir A1 - Pasternak, Hartmut T1 - Mathematical model for the prediction of strength degradation of composites subjected to constant amplitude fatigue T2 - International Journal of Fatigue Y1 - 2017 U6 - https://doi.org/10.1016/j.ijfatigue.2017.06.032 SN - 0142-1123 VL - 103 SP - 478 EP - 487 ER -