@inproceedings{PasternakChwastek, author = {Pasternak, Hartmut and Chwastek, Agnieszka}, title = {Fatique assessment of non-load carrying fillet welds after seams repair and treatment procedures}, series = {7th European Conference on Steel and Composite Structures, Eurosteel, Neapel, 2014}, booktitle = {7th European Conference on Steel and Composite Structures, Eurosteel, Neapel, 2014}, publisher = {ECCS European Convention for Constructional Steelwork}, address = {Brussels}, isbn = {978-92-9147-121-8}, pages = {263 -- 264}, language = {en} } @inproceedings{PasternakBartholomeBulkowski, author = {Pasternak, Hartmut and Bartholom{\´e}, Susanne Elisabeth and Bulkowski, Marcin}, title = {Retrofitting of Cracks in Steel Construction - using CFRP Laminates}, series = {7th European Conference on Steel and Composite Structures, Eurosteel, Neapel 2014}, booktitle = {7th European Conference on Steel and Composite Structures, Eurosteel, Neapel 2014}, publisher = {ECCS European Convention for Constructional Steelwork}, address = {Brussels}, isbn = {978-92-9147-121-8}, language = {en} } @misc{PasternakSahellie, author = {Pasternak, Hartmut and Sahellie, Samer}, title = {Epoxy- and acrylic-bonded joints for strengthening lightweight steel girders}, series = {Stahlbau}, volume = {84}, journal = {Stahlbau}, number = {8}, issn = {0038-9145}, pages = {577 -- 583}, language = {en} } @misc{PasternakSahellie, author = {Pasternak, Hartmut and Sahellie, Samer}, title = {Expectancy of the lifetime of bonded steel joints due to long-term shear loading}, series = {Archives of Civil and Mechanical Engineering}, volume = {15}, journal = {Archives of Civil and Mechanical Engineering}, number = {4}, issn = {1644-9665}, doi = {10.1016/j.acme.2015.05.004}, pages = {1061 -- 1069}, language = {en} } @misc{PasternakCiupackSchieletal., author = {Pasternak, Hartmut and Ciupack, Yvonne and Schiel, Manuel and Ince, Erdeniz}, title = {Adhesive bonded joints in steel structures}, series = {Steel Construction}, volume = {7}, journal = {Steel Construction}, number = {3}, issn = {1867-0539}, pages = {173 -- 182}, language = {en} } @inproceedings{PasternakKrauscheLaunert, author = {Pasternak, Hartmut and Krausche, Thomas and Launert, Benjamin}, title = {Welding of thick steel plates under site conditions}, series = {7th European Conference on Steel and Composite Structures, Eurosteel, Neapel, 2014}, booktitle = {7th European Conference on Steel and Composite Structures, Eurosteel, Neapel, 2014}, publisher = {ECCS European Convention for Constructional Steelwork}, address = {Brussels}, isbn = {978-92-9147-121-8}, pages = {109 -- 110}, language = {en} } @inproceedings{PasternakCiupackSchieletal., author = {Pasternak, Hartmut and Ciupack, Yvonne and Schiel, Manuel and Ince, Erdeniz}, title = {Adhesive bonded joints in steel structures}, series = {7th European Conference on Steel and Composite Structures, Eurosteel, Neapel, 2014}, booktitle = {7th European Conference on Steel and Composite Structures, Eurosteel, Neapel, 2014}, publisher = {ECCS European Convention for Constructional Steelwork}, address = {Brussels}, isbn = {978-92-9147-121-8}, pages = {265 -- 266}, language = {en} } @inproceedings{PasternakStojković, author = {Pasternak, Hartmut and Stojković, Nenad}, title = {Fatique of adhesively bonded structural elements - residuel strenght models}, series = {14th International Scientific Conference VSU 2014, Sofia, 2014, Vol. 2}, booktitle = {14th International Scientific Conference VSU 2014, Sofia, 2014, Vol. 2}, publisher = {VSU}, pages = {34 -- 39}, language = {en} } @inproceedings{PasternakSahellie, author = {Pasternak, Hartmut and Sahellie, Samer}, title = {Concentration of the normal stresses in the adherends of adhesively-bonded double lap steel joints due to reducing the width of the bonded area}, series = {14th International Scientific Conference VSU 2014, Sofia, 2014, vol. 2}, booktitle = {14th International Scientific Conference VSU 2014, Sofia, 2014, vol. 2}, publisher = {Univ. of Structural Engineering and Architecture}, address = {Sofia}, pages = {197 -- 202}, language = {en} } @misc{SchlaichBleicherPasternak, author = {Schlaich, Mike and Bleicher, Achim and Pasternak, Hartmut}, title = {Der Porsche Pavillon in Monocoque-Bauweise}, series = {Bauingenieur}, volume = {89}, journal = {Bauingenieur}, number = {1}, issn = {1436-4867}, pages = {1 -- 10}, language = {de} } @misc{PasternakKrauscheNiemann, author = {Pasternak, Hartmut and Krausche, Thomas and Niemann, M.}, title = {Umbau eines Schulgeb{\"a}udes der Heinrich-Nordhoff-Gesamtschule in Wolfsburg}, series = {Bauingenieur}, volume = {89}, journal = {Bauingenieur}, number = {4}, issn = {1436-4867}, pages = {182 -- 185}, language = {de} } @misc{FeldmannGesslerUmmenhoferetal., author = {Feldmann, Markus and Geßler, Achim and Ummenhofer, Thomas and G{\"o}tz, Frank and Bartholom{\´e}, Susanne Elisabeth and Pasternak, Hartmut}, title = {Zum Kleben von CFK-Lamellen im Stahlbau}, series = {BTU Stahlbau-Symposium 2014, Cottbus, 2014}, journal = {BTU Stahlbau-Symposium 2014, Cottbus, 2014}, publisher = {BTU}, address = {Cottbus [u.a.]}, pages = {83 -- 90}, language = {de} } @inproceedings{PasternakMoradiKrausche, author = {Pasternak, Hartmut and Moradi, Milad and Krausche, Thomas}, title = {Reconstruction of a school building in Wolfsburg, Germany}, series = {Tubular Structures XV, Proceedings of the 15th International Symposium on Tubular Structures, Rio de Janeiro, Brazil, 27-29 May 2015}, booktitle = {Tubular Structures XV, Proceedings of the 15th International Symposium on Tubular Structures, Rio de Janeiro, Brazil, 27-29 May 2015}, publisher = {CRC Press}, address = {Hoboken}, isbn = {978-1-138-02837-1}, pages = {31 -- 35}, language = {en} } @misc{PasternakLaunertKrausche, author = {Pasternak, Hartmut and Launert, Benjamin and Krausche, Thomas}, title = {Welding of girders with thick plates — Fabrication, measurement and simulation}, series = {Journal of Constructional Steel Research}, volume = {Vol. 115}, journal = {Journal of Constructional Steel Research}, issn = {0143-974X}, doi = {10.1016/j.jcsr.2015.08.037}, pages = {407 -- 416}, abstract = {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.}, language = {en} } @inproceedings{PasternakKrauscheLaunert, author = {Pasternak, Hartmut and Krausche, Thomas and Launert, Benjamin}, title = {Welded construction site joints in bridges}, series = {Steel Bridges: Innovation \& New Challenges, 8th International Symposium on Steel Bridges, Istanbul, 2015}, booktitle = {Steel Bridges: Innovation \& New Challenges, 8th International Symposium on Steel Bridges, Istanbul, 2015}, publisher = {Turkish Constructional Steelwork Association (TUCSA)}, address = {Istanbul, Turkey}, isbn = {978-605-65900-2-3}, pages = {315 -- 320}, abstract = {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.}, language = {en} } @book{NitschkePagelKlassenPasternaketal., author = {Nitschke-Pagel, Thomas and Klassen, Jakob and Pasternak, Hartmut and Launert, Benjamin and Krausche, Thomas}, title = {P 858 - Schweißen dicker Bleche unter Baustellenbedingungen - Beurteilung des Einflusses auf das Tragverhalten von Montagest{\"o}ßen}, publisher = {Verlag und Vertriebsgesellschaft mbH}, address = {D{\"u}sseldorf}, isbn = {978-3-942541-69-5}, abstract = {Beim Aufbau großer Stahlstrukturen im Br{\"u}cken- oder Stahlhochbau wird heute vermehrt auf modulare Fabrikfertigung gesetzt. Ein F{\"u}gen dieser Module auf der Baustelle zu einer Gesamtstruktur ist aber weiterhin notwendig. Als F{\"u}geverfahren wird hier h{\"a}ufig das MAG-Mehrlagenschweißen eingesetzt. Gerade an dicken Blechen stellen Baustellenschweißungen nicht nur besondere Anforderungen an den ausf{\"u}hrenden Betrieb, die Bauleitung und Bau{\"u}berwachung, sondern auch an den Konstrukteur. Wichtig f{\"u}r den Konstrukteur ist die Kenntnis der sich durch Schweißungen einstellenden Schrumpfung der Bauteile, der auftretenden Verz{\"u}ge und Eigenspannungen. Gerade bei Baustellenschweißungen m{\"u}ssen diese Aspekte in der Konstruktionsphase der Einzelkomponenten mit ber{\"u}cksichtigt werden, um die erforderlichen Toleranzen bei der Montage einzuhalten. Eine genaue Kenntnis der durch Schweißungen verursachten Ph{\"a}nomene ist in den Konstruktions- und Montagebetrieben oft nur aus mehrj{\"a}hrigen Erfahrungen vorhanden. Ein grundlegendes, vollst{\"a}ndiges Bild der Abl{\"a}ufe beim Schweißen auf der Baustelle, das es erm{\"o}glicht, dieses Wissen auf neue Konstruktionen zu {\"u}bertragen, fehlt bisher. Insbesondere f{\"u}r die immer {\"o}fter im Br{\"u}cken- und Stahlhochbau eingesetzten h{\"o}herfesten Feinkornbaust{\"a}hle (z.B. S460) ist die Kenntnis des Verhaltens bei Baustellenschweißungen notwendig. Hier setzt der Forschungsantrag an. Mit Hilfe der Schweißsimulation k{\"o}nnen die Auswirkungen von Schweißn{\"a}hten, wie die Entstehung von Verz{\"u}gen und Eigenspannungen am Bauteil, global dargestellt werden. Eine anschließende Struktursimulationen (Festigkeits- und Steifigkeitsberechnungen) mit aus der Schweißsimulation integrierten Ergebnissen bildet die Basis f{\"u}r erg{\"a}nzende Untersuchungen. Montagest{\"o}ße sind außerdem durch Verschmutzung und Witterung negativ beeinflusst. Die Montage kann beispielsweise bei niedrigen Temperaturen unterhalb des Gefrierpunkts durchgef{\"u}hrt werden m{\"u}ssen. Diese Situation wurde in einer Klimakammer simuliert und die Auswirkungen der Umgebungstemperatur bei der Montage auf das Tragverhalten der Verbindung untersucht. F{\"u}r die im Rahmen des Vorhabens untersuchten F{\"a}lle ist kein Einfluss variierender Umgebungstemperaturen bis -10 °C auf die resultierenden Schweißeigenspannungen festzustellen. Der Vergleich von Verzug und Eigenspannung gegen{\"u}ber normativ vorgegeben Toleranzwerten sowie vereinfachten Ingenieurmodellen f{\"u}r die Approximation des Eigenspannungsverlaufs zeigt große Defizite. Bei realit{\"a}tsnaher Implementierung der Eigenspannungen in die Traglastberechnung k{\"o}nnen z.T. große Reserven im Rahmen der nichtlinearen Traglastberechnung ausgenutzt werden.}, language = {de} } @misc{PasternakKrausche, author = {Pasternak, Hartmut and Krausche, Thomas}, title = {The Porsche Pavilion in the Autostadt Wolfsburg, Germany}, series = {Procedia Engineering}, journal = {Procedia Engineering}, number = {57}, issn = {1877-7058}, doi = {10.1016/j.proeng.2013.04.010}, pages = {63 -- 69}, language = {en} } @misc{BartholomePasternakFeldmannetal., author = {Bartholom{\´e}, Susanne Elisabeth and Pasternak, Hartmut and Feldmann, Markus and Geßler, Achim and Ummenhofer, Thomas and G{\"o}tz, Frank}, title = {Verst{\"a}rkung von Stahlkonstruktionen durch geklebte CFK-Lamellen}, series = {20. DASt-Forschungskolloquium in Essen, 08./09. M{\"a}rz 2016}, journal = {20. DASt-Forschungskolloquium in Essen, 08./09. M{\"a}rz 2016}, publisher = {Frehner Consulting}, address = {F{\"u}ssen}, isbn = {978-3-941687-19-6}, pages = {89 -- 94}, language = {de} } @inproceedings{BartholomePasternakFeldmannetal., author = {Bartholom{\´e}, Susanne Elisabeth and Pasternak, Hartmut and Feldmann, Markus and Geßler, Achim and Ummenhofer, Thomas and G{\"o}tz, Frank}, title = {Kleben von CFK-Lamellen im Stahlbau}, series = {DVS Congress 2015, Große Schweißtechnische Tagung, N{\"u}rnberg}, booktitle = {DVS Congress 2015, Große Schweißtechnische Tagung, N{\"u}rnberg}, publisher = {DVS Media}, address = {D{\"u}sseldorf}, isbn = {978-3-945023-46-4}, pages = {927 -- 932}, language = {de} } @inproceedings{BartholomePasternakFeldmannetal., author = {Bartholom{\´e}, Susanne Elisabeth and Pasternak, Hartmut and Feldmann, Markus and Geßler, Achim and Ummenhofer, Thomas}, title = {Systematische Untersuchung zur Verst{\"a}rkung von Stahlkonstruktionen mit kohlefaserverst{\"a}rkten Kunststoffen (CFK)}, series = {Tagungsband, 16. Kolloquium Gemeinsame Forschung in der Klebtechnik, K{\"o}ln, M{\"a}rz 2016}, booktitle = {Tagungsband, 16. Kolloquium Gemeinsame Forschung in der Klebtechnik, K{\"o}ln, M{\"a}rz 2016}, publisher = {DECHEMA, Gesellschaft f{\"u}r Chemische Technik und Biotechnologie e.V.}, address = {Frankfurt am Main}, pages = {45 -- 47}, language = {de} } @inproceedings{BartholomePasternakBulkowski, author = {Bartholom{\´e}, Susanne Elisabeth and Pasternak, Hartmut and Bulkowski, Marcin}, title = {Risssanierung von dynamisch beanspruchten Stahlbauteilen mit kohlenfaserverst{\"a}rkten Kunststoffen (CFK-Lamellen)}, series = {DVS Congress 2015, Große Schweißtechnische Tagung, N{\"u}rnberg}, booktitle = {DVS Congress 2015, Große Schweißtechnische Tagung, N{\"u}rnberg}, publisher = {DVS Media}, address = {D{\"u}sseldorf}, isbn = {978-3-945023-46-4}, pages = {597 -- 602}, language = {de} } @misc{PasternakKubieniec, author = {Pasternak, Hartmut and Kubieniec, Gabriel}, title = {Implementation of longitudinal welding stresses into structural calculation of steel structures}, series = {JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT}, volume = {22}, journal = {JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT}, number = {1}, issn = {1392-3730}, doi = {10.3846/13923730.2014.994029}, pages = {47 -- 55}, language = {en} } @misc{PasternakSahellie, author = {Pasternak, Hartmut and Sahellie, Samer}, title = {Conversion factors of the temperature effect on the shear strength of adhesively bonded steel joints}, series = {Journal of civil engineering and management}, volume = {22}, journal = {Journal of civil engineering and management}, number = {5}, issn = {1392-3730}, doi = {10.3846/13923730.2015.1068848}, pages = {666 -- 672}, language = {en} } @inproceedings{LaunertRhodePasternaketal., author = {Launert, Benjamin and Rhode, Michael and Pasternak, Hartmut and Kannengießer, Thomas}, title = {Welding residual stresses in high-strength steel. Experimental results}, series = {The International Colloquium on Stability and Ductility of Steel Structures}, booktitle = {The International Colloquium on Stability and Ductility of Steel Structures}, editor = {Dubina, Dan and Ungureanu, Viorel}, edition = {2016 edition}, publisher = {Ernst \& Sohn}, isbn = {978-92-9147-133-1}, pages = {517 -- 524}, abstract = {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.}, language = {en} } @inproceedings{CiupackPasternakLedeckyetal., author = {Ciupack, Yvonne and Pasternak, Hartmut and Ledecky, Lukas and Mette, Christoph and Stammen, Elisabeth and Dilger, Klaus}, title = {Adhesive bonded steel structures under cyclic loading}, series = {Proceedings of the METNET Seminar 2015 in Budapest, 2015}, booktitle = {Proceedings of the METNET Seminar 2015 in Budapest, 2015}, editor = {Virdi, Kuldeep and Tenhunen, Lauri}, publisher = {HAMK University of Applied Sciences}, address = {H{\"a}meenlinna}, isbn = {978-951-784-762-9}, pages = {90 -- 101}, language = {en} } @inproceedings{StojkovićLedeckyCiupacketal., author = {Stojković, Nenad and Ledecky, Lukas and Ciupack, Yvonne and Pasternak, Hartmut and Mette, Christoph and Stammen, Elisabeth and Dilger, Klaus}, title = {Tensile strength of adhesively bonded fa{\c{c}}ade joints}, series = {The Sixth International Conference Civil Engineering - Science \& Practice, Montenegro, 2016}, booktitle = {The Sixth International Conference Civil Engineering - Science \& Practice, Montenegro, 2016}, isbn = {978-86-82707-30-1}, pages = {273 -- 280}, language = {en} } @inproceedings{JaegerPasternak, author = {J{\"a}ger, A. and Pasternak, Hartmut}, title = {Grundlegende Studien zum Beulverhalten von engringversteiften Kreiszylinderschalen unter Axialdruck}, series = {Offen im Denken, 20. DASt-Forschungskolloquium in Essen, 08./09. M{\"a}rz 2016}, booktitle = {Offen im Denken, 20. DASt-Forschungskolloquium in Essen, 08./09. M{\"a}rz 2016}, publisher = {Deutscher Ausschuß f{\"u}r Stahlbau DASt}, address = {D{\"u}sseldorf}, isbn = {978-3-941687-19-6}, pages = {38 -- 42}, language = {de} } @inproceedings{LedeckyStojkovićCiupacketal., author = {Ledecky, Lukas and Stojković, Nenad and Ciupack, Yvonne and Pasternak, Hartmut and Mette, Christoph and Fischer, Vitali and Stammen, Elisabeth and Dilger, Klaus}, title = {Service loading and fatigue behavior of adhesively bonded steel-steel fa{\c{c}}ade joints}, series = {16th International Scientific Conference VSU 2016, Sofia, 2016, vol. 1}, booktitle = {16th International Scientific Conference VSU 2016, Sofia, 2016, vol. 1}, publisher = {VSU}, address = {Sofia}, pages = {187 -- 192}, language = {en} } @inproceedings{PasternakLaunertKannengiesseretal., author = {Pasternak, Hartmut and Launert, Benjamin and Kannengießer, Thomas and Rhode, Michael}, title = {Residual stresses and imperfections in welded high-strength I-shape members}, series = {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}, booktitle = {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}, editor = {Zingoni, Alphose}, publisher = {Taylor \& Francis}, address = {London}, isbn = {978-1-138-02927-9}, pages = {403 -- 404}, abstract = {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.}, language = {en} } @inproceedings{PasternakKrausche, author = {Pasternak, Hartmut and Krausche, Thomas}, title = {Details of the steel assembly of a membrane-cladded double ­ curved cable net roof}, series = {ICCAEE 2016 Kuala Lumpur/Malaysia, 2nd International Congress on Technology - Engineering \& Science}, booktitle = {ICCAEE 2016 Kuala Lumpur/Malaysia, 2nd International Congress on Technology - Engineering \& Science}, publisher = {University of Malaysia}, address = {Pahang}, language = {en} } @misc{BartholomePasternakFeldmannetal., author = {Bartholom{\´e}, Susanne Elisabeth and Pasternak, Hartmut and Feldmann, Markus and Geßler, Achim and Ummenhofer, Thomas and Ruff, Daniel}, title = {Alternative Verst{\"a}rkungsmaßnahme im Stahlbau mit aufgeklebten unidirektionalen CFK-Lamellen}, series = {Schweißen und Schneiden}, volume = {68}, journal = {Schweißen und Schneiden}, number = {8}, issn = {0036-7184}, pages = {490 -- 499}, language = {de} } @misc{JaegerPasternak, author = {J{\"a}ger, Andreas and Pasternak, Hartmut}, title = {Studien zum Beulverhalten von eng ringversteiften Kreiszylinderschalen unter Axialdruck}, series = {Bauingenieur}, volume = {91}, journal = {Bauingenieur}, number = {10}, issn = {0005-6650}, pages = {401 -- 409}, language = {de} } @misc{BartholomePasternakFeldmannetal., author = {Bartholom{\´e}, Susanne Elisabeth and Pasternak, Hartmut and Feldmann, Markus and Geßler, Achim and Ummenhofer, Thomas and Ruff, Daniel}, title = {Geklebte CFK-Lamellen verst{\"a}rken Stahlbauteile}, series = {Adh{\"a}sion}, volume = {60}, journal = {Adh{\"a}sion}, number = {9}, issn = {1619-1919}, pages = {42 -- 49}, language = {de} } @misc{BartholomePasternak, author = {Bartholom{\´e}, Susanne Elisabeth and Pasternak, Hartmut}, title = {Tr{\"a}ger mit schlanken, wabenf{\"o}rmig strukturierten Stegen - Versuch und Simulation}, series = {Stahlbau}, volume = {85}, journal = {Stahlbau}, number = {11}, issn = {1437-1049}, doi = {10.1002/stab.201610423}, pages = {724 -- 732}, language = {de} } @inproceedings{LaunertRhodeKrommetal., author = {Launert, Benjamin and Rhode, Michael and Kromm, Arne and Pasternak, Hartmut and Kannengießer, Thomas}, title = {Residual Stress Influence on the Flexural Buckling of Welded I-Girders}, series = {Residual Stresses 2016 - ICRS-10}, booktitle = {Residual Stresses 2016 - ICRS-10}, editor = {Holden, Thomas M. and Mur{\´a}nsky, Ondrej and Edwards, Lyndon}, publisher = {Materials Research Forum LLC}, address = {Millersville, PA}, isbn = {978-1-94529116-6}, doi = {10.21741/9781945291173-19}, pages = {109 -- 114}, abstract = {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.}, language = {en} } @inproceedings{KrommRhodeLaunertetal., author = {Kromm, Arne and Rhode, Michael and Launert, Benjamin and Dixneit, Jonny and Kannengießer, Thomas and Pasternak, Hartmut}, title = {Combining Sectioning Method and X-Ray Diffraction for Evaluation of Residual Stresses in Welded High Strength Steel Components}, series = {Residual Stresses 2016 - ICRS-10}, booktitle = {Residual Stresses 2016 - ICRS-10}, editor = {Holden, Thomas M. and Mur{\´a}nsky, Ondrej and Edwards, Lyndon}, publisher = {Materials Research Forum LLC}, address = {Millersville, PA}, isbn = {978-1-94529116-6}, doi = {10.21741/9781945291173-28}, pages = {163 -- 168}, abstract = {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.}, language = {en} } @misc{LaunertSzczerbaGajewskietal., author = {Launert, Benjamin and Szczerba, Radosław and Gajewski, Marcin and Rhode, Michael and Pasternak, Hartmut and Giżejowski, Marian}, title = {The buckling resistance of welded plate girders taking into account the influence of post-welding imperfections - Part 1: Parameter study}, series = {Materials Testing}, volume = {59}, journal = {Materials Testing}, number = {1}, issn = {0025-5300}, doi = {10.3139/120.110964}, pages = {47 -- 56}, abstract = {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.}, language = {en} } @misc{LaunertRhodeKrommetal., author = {Launert, Benjamin and Rhode, Michael and Kromm, Arne and Pasternak, Hartmut and Kannengießer, Thomas}, title = {Measurement and numerical modeling of residual stresses in welded HSLA component-like I-girders}, series = {Welding in the World}, volume = {61}, journal = {Welding in the World}, number = {2}, issn = {0043-2288}, doi = {10.1007/s40194-016-0413-x}, pages = {223 -- 229}, abstract = {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.}, language = {en} } @misc{LoebjinskiRugPasternak, author = {Loebjinski, Maria and Rug, Wolfgang and Pasternak, Hartmut}, title = {Zuverl{\"a}ssigkeitsbewertung von Holzbauteilen im Bestand}, series = {Bauingenieur}, volume = {92}, journal = {Bauingenieur}, number = {2}, issn = {0005-6650}, pages = {65 -- 73}, abstract = {Die aktuellen Bemessungsnormen des Eurocodes beinhalten keine gesonderten Regelungen f{\"u}r bestehende Bauwerke. Dennoch sind diese aus verschiedenen Gr{\"u}nden spezifisch zu bemessen. Dazu geh{\"o}ren sowohl {\"o}ko-nomische Gr{\"u}nde, als auch Anforderungen an die Erhaltung von historischen Konstruktionen. Dieser Beitrag fasst Grundlagen zur Zuverl{\"a}ssigkeitstheorie und zur Ermittlung von Teilsicherheitsbeiwerten zusammen, stellt den aktuellen Stand der Technik zu Normen und Standards der zuverl{\"a}ssigkeitstheoretischen Bemessung und zur Behandlung von Bestandsbauten in der Bemessung dar und zeigt mit vereinfachten Rechnungen das Opti-mierungspotential der Teilsicherheitsbeiwerte f{\"u}r historische Holzkonstruktionen auf.}, language = {de} } @inproceedings{CiupackPasternak, author = {Ciupack, Yvonne and Pasternak, Hartmut}, title = {Bonding Technology in Steel Structures, a Summary of Research Activities at Chair of Steel and Timber Structures}, series = {Proceedings of the METNET Seminar 2016 in Castellon}, booktitle = {Proceedings of the METNET Seminar 2016 in Castellon}, editor = {Virdi, Kuldeep and Tenhunen, Lauri}, address = {H{\"a}meenlinna}, isbn = {978-951-784-784-1}, pages = {19 -- 30}, language = {en} } @misc{PasternakLaunertKannengiesseretal., author = {Pasternak, Hartmut and Launert, Benjamin and Kannengießer, Thomas and Rhode, Michael}, title = {Advanced Residual Stress Assessment of Plate Girders Through Welding Simulation}, series = {Procedia Engineering}, volume = {172}, journal = {Procedia Engineering}, issn = {1877-7058}, doi = {10.1016/j.proeng.2017.02.013}, pages = {23 -- 30}, abstract = {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.}, language = {en} } @misc{KemperLedeckyFeldmannetal., author = {Kemper, Frank and Ledecky, Lukas and Feldmann, Markus and Pasternak, Hartmut and Fischer, Vitali}, title = {Zeitabh{\"a}ngige Windbeanspruchungen von geklebten Fassadenanschl{\"u}ssen}, series = {Bauingenieur}, volume = {92}, journal = {Bauingenieur}, number = {3}, issn = {1436-4867}, pages = {115 -- 122}, abstract = {F{\"u}r die Bemessung lastabtragender Klebverbindungen im Fassadenbereich ist zu beachten, dass die Windbelastungen auf den Bauwerksoberfl{\"a}chen sowohl zeitlich als auch r{\"a}umlich ver{\"a}nderlich sind. W{\"a}hrend f{\"u}r {\"u}bliche Fassadenanschl{\"u}sse eine Bemessung mit charakteristischen Extremwerten ausreichend ist, muss beim Einsatz von sowohl h{\"o}hermoduligen (z.B. Acrylat) als auch niedrigmoduligen (z.B. Polyurethan) Klebstoffen, die beide ein zeit- und temperaturabh{\"a}ngiges Materialverhalten aufweisen, eine vollst{\"a}ndige Beschreibung dieser zeitbezogenen Lasteinwirkungen erfolgen. Nur dadurch wird letztlich die erforderliche betriebsfeste Auslegung eines geklebten Fassadenanschlusses erm{\"o}glicht. Im vorliegenden Beitrag wird die Ermittlung von zeitbezogenen Lasteinwirkungen und die Berechnung der daraus resultierenden Beanspruchungs-Zeit-Funktionen infolge einer nat{\"u}rlichen Windeinwirkungen auf Basis von Windkanalversuchen und Windstatistik thematisiert. Anhand geeigneter Z{\"a}hlverfahren und unter Ber{\"u}cksichtigung von klebstoffspezifischen Materialeigenschaften wird exemplarisch aufgezeigt, inwiefern unterschiedliche Fassadenpositionen und Windeigenschaften f{\"u}r die Auslegung von geklebten Fassadenanschl{\"u}ssen von Bedeutung sind.}, language = {de} } @inproceedings{SimonMoradiHildebrandetal., author = {Simon, Flaviu and Moradi, Milad and Hildebrand, J{\"o}rg and Pasternak, Hartmut}, title = {The influence of the welding sequence on the load bearing capacity and stress distribution of square hollow section steel joints}, series = {Simulationsforum 2016, Schweißen und W{\"a}rmebehandlung, Weimar, Tagungsband 08.-10. November 2016}, booktitle = {Simulationsforum 2016, Schweißen und W{\"a}rmebehandlung, Weimar, Tagungsband 08.-10. November 2016}, editor = {Hildebrand, J{\"o}rg and Loose, Tobias and Reich, Michael}, publisher = {Verein zur F{\"o}rderung der numerischen Analyse der W{\"a}rmebehandlungs- und Schweißprozesse e.V.}, address = {Weimar}, isbn = {978-3-00-054805-5}, pages = {176 -- 187}, abstract = {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.}, language = {en} } @inproceedings{ShlychkovaPasternak, author = {Shlychkova, Darita and Pasternak, Hartmut}, title = {Numerical analysis of lightweight structured sandwich beams made of steel}, series = {16th International Scientific Conference VSU 2016, Sofia, 2016, vol. 1}, booktitle = {16th International Scientific Conference VSU 2016, Sofia, 2016, vol. 1}, publisher = {VSU}, address = {Sofia}, pages = {318 -- 323}, abstract = {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.}, language = {en} } @inproceedings{LedeckyCiupackPasternaketal., author = {Ledecky, Lukas and Ciupack, Yvonne and Pasternak, Hartmut and Fischer, Vitali and Stammen, Elisabeth and Dilger, Klaus}, title = {Untersuchungen zum Tragverhalten und der Lebensdauer von Klebverbindungen im Stahlbau unter zyklischen Belastungen (LebKleb)}, series = {17. Kolloquium Gemeinsame Forschung in der Klebtechnik, Tagungsband, 14. - 15. Februar 2017}, booktitle = {17. Kolloquium Gemeinsame Forschung in der Klebtechnik, Tagungsband, 14. - 15. Februar 2017}, publisher = {DECHEMA}, address = {Frankfurt am Main}, pages = {37 -- 38}, language = {de} } @inproceedings{LedeckyCiupackPasternaketal., author = {Ledecky, Lukas and Ciupack, Yvonne and Pasternak, Hartmut and Mette, Christoph and Stammen, Elisabeth and Dilger, Klaus}, title = {Untersuchungen zum Tragverhalten und der Lebensdauer von Klebverbindungen im Stahlbau unter zyklischen Belastungen (LebKleb)}, series = {16. Kolloquium Gemeinsame Forschung in der Klebtechnik, K{\"o}ln, 2016}, booktitle = {16. Kolloquium Gemeinsame Forschung in der Klebtechnik, K{\"o}ln, 2016}, publisher = {DECHEMA}, address = {Frankfurt am Main}, pages = {39 -- 41}, language = {de} } @misc{CiupackPasternakMetteetal., author = {Ciupack, Yvonne and Pasternak, Hartmut and Mette, Christoph and Stammen, Elisabeth and Dilger, Klaus}, title = {Adhesive bonding in steel construction - Challenge and innovation}, series = {Procedia Engineering}, volume = {172}, journal = {Procedia Engineering}, issn = {1877-7058}, doi = {10.1016/j.proeng.2017.02.048}, pages = {186 -- 193}, language = {en} } @inproceedings{LiPasternak, author = {Li, Zheng and Pasternak, Hartmut}, title = {Development of a stochastic material model at constant stress distribution in steel construction}, series = {16th International Scientific Conference VSU 2016, Sofia, 2016, vol. 1}, booktitle = {16th International Scientific Conference VSU 2016, Sofia, 2016, vol. 1}, publisher = {VSU}, address = {Sofia}, pages = {193 -- 198}, abstract = {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.}, language = {en} } @inproceedings{PasternakKrausche, author = {Pasternak, Hartmut and Krausche, Thomas}, title = {A special Construction Site: the Guyed Mast at Torfhaus in the Harz Mountains, Germany}, series = {Risk and Safety Engineering, 12th International Conference, Kopaonik, 2017}, booktitle = {Risk and Safety Engineering, 12th International Conference, Kopaonik, 2017}, publisher = {The Higher Education Technical School of Professional Studies}, address = {Novi Sad}, isbn = {978-86-6211-107-4}, pages = {540 -- 545}, language = {en} } @misc{LinkeRugPasternak, author = {Linke, Gunter and Rug, Wolfgang and Pasternak, Hartmut}, title = {Festigkeitssortierung von Bauholz in historischen Geb{\"a}uden - Bericht zum Stand der Technik}, series = {Bauingenieur}, volume = {92}, journal = {Bauingenieur}, number = {5}, pages = {229 -- 236}, language = {de} } @misc{StojkovićFolićPasternak, author = {Stojković, Nenad and Folić, Radomir and Pasternak, Hartmut}, title = {Mathematical model for the prediction of strength degradation of composites subjected to constant amplitude fatigue}, series = {International Journal of Fatigue}, volume = {103}, journal = {International Journal of Fatigue}, issn = {0142-1123}, doi = {10.1016/j.ijfatigue.2017.06.032}, pages = {478 -- 487}, language = {en} }