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 -