TY - GEN A1 - Zerbst, Uwe A1 - Ainsworth, R. A. A1 - Madia, Mauro ED - Klingbeil, D. ED - Vormwald, M. ED - Eulitz, K.-G. T1 - Reference load versus limit load in engineering flaw assessment: A proposal for a hybrid analysis option N2 - The net section limit load FY is a key input parameter for the accuracy of any elastic-plastic flaw assessment procedure of the R6 type. Unfortunately available limit load solutions are of variable quality since they have been obtained over decades by different methods. As a consequence the results of the fracture analyses such as the critical load or crack size are limited in their accuracy and are often significantly conservative. A further problem is that common limit load solutions based on ligament yielding are inadequate in a number of cases even for through crack configurations and should be replaced by some kind of local yielding solutions. In the present paper a simple and straightforward reference load definition is proposed instead of the limit load which strictly corresponds to a ligament yielding parameter Lr = 1 in the R6 Routine and similar approaches such as SINTAP and FITNET. This can be determined by finite element simulation for any geometry. In addition to a previous study on thin wall notched plates the method is applied to plates containing shallow semi-elliptical surface cracks. The results demonstrate that the approach provides a suitable extension and improvement of the existing methods. T2 - 18th European conference on fracture (ECF 18) - Fracture of materials and structures from micro to macro scale CY - Dresden, Germany DA - 2010-08-30 KW - Flaw assessment KW - Reference stress method KW - R6 procedure KW - EPRI method KW - SINTAP KW - FITNET KW - Limit load KW - Reference load PY - 2010 SN - 978-3-00-031802-3 IS - Paper 81 SP - 1 EP - 11 AN - OPUS4-22329 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zerbst, Uwe A1 - Ainsworth, R. A. A1 - Madia, Mauro T1 - Reference load versus limit load in engineering flaw assessment: A proposal for a hybrid analysis option N2 - The net section limit load FY necessary for assessment at static loading is a key input for the accuracy of any elastic–plastic flaw assessment procedure of the R6 type. Unfortunately available limit load solutions are of variable quality since they have been obtained over decades by different methods. As a consequence the results of the fracture analyses such as the critical load or crack size are limited in their accuracy and are often significantly conservative. Further, common limit load solutions based on ligament yielding are inadequate in a number of cases even for through crack configurations and should be replaced by some kind of local yielding solutions. In the present paper a simple and straightforward reference load definition is proposed instead of the limit load which strictly corresponds to a ligament yielding parameter Lr = 1 in the R6 Routine and similar approaches such as the European SINTAP and FITNET methods. This can be determined by finite element simulation for any geometry. In addition to a previous study on thin wall notched plates the method is applied to plates containing shallow semi-elliptical surface cracks. The results demonstrate that the approach provides a suitable extension and improvement of the existing methods. KW - Flaw assessment KW - Reference stress method KW - R6 procedure KW - SINTAP KW - FITNET KW - Limit load KW - Reference load PY - 2012 U6 - https://doi.org/10.1016/j.engfracmech.2011.10.018 SN - 0013-7944 SN - 1873-7315 VL - 91 SP - 62 EP - 72 PB - Elsevier Science CY - Kidlington AN - OPUS4-27279 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zerbst, Uwe A1 - Ainsworth, R. A. A1 - Madia, Mauro T1 - Grenzlast oder Referenzlast? - Vorschlag für eine hybride Vorgehensweise bei der elastisch-plastischen Bauteilbewertung T2 - 42. Tagung des DVM-Arbeitskreises Bruchvorgänge - Bruchmechanische Werkstoff- und Bauteilbewertung: Beanspruchungsanalyse, Prüfmethoden und Anwendungen CY - Paderborn, Deutschland DA - 2010-02-23 KW - Bruchmechanische Bauteilbewertung KW - EPRI-Methode KW - Referenzspannungsmethode KW - R6-Routine KW - SINTAP KW - FITNET KW - FKM-Richtlinie KW - Grenzlast KW - Referenzlast PY - 2010 SP - 183 EP - 194 AN - OPUS4-22493 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zerbst, Uwe A1 - Ainsworth, R. A. A1 - Beier, H.T. A1 - Pisarski, H. A1 - Zhang, Z. L. A1 - Nikbin, K. A1 - Nitschke-Pagel, T. A1 - Münstermann, S. A1 - Kucharczyk, P. A1 - Klingbeil, Dietmar T1 - Review on fracture and crack propagation in weldments - A fracture mechanics perspective N2 - Welding is one of the most common methods in industrial practice for joining components. Its main advantages are high speed in manufacturing combined with low costs and, usually, a high degree of flexibility, integrity and reliability. Nevertheless, welding is a highly complex metallurgical process and, therefore, weldments are susceptible to material discontinuities, flaws and residual stresses which may lead to structural failure and life time reduction. As a consequence weldments are an important field of fracture mechanics methods although its application is more complex than for homogeneous or non-welded structures. The aim of the paper is to provide an overview on the current state of fracture mechanics application to weldments. It starts by discussing the specific features which any fracture mechanics analysis of weldments has to take into account. Then, the experimental determination of fracture toughness, fatigue crack propagation and tensile properties of weldments is addressed. Finally, the analytical determination of the crack driving force in components and structural integrity assessment approaches for weldments are presented. KW - Weldments KW - Fracture mechanics KW - Fracture toughness KW - Fatigue crack propagation KW - Residual stresses KW - Strength mismatch PY - 2014 U6 - https://doi.org/10.1016/j.engfracmech.2014.05.012 SN - 0013-7944 SN - 1873-7315 VL - 132 SP - 200 EP - 276 PB - Elsevier Science CY - Kidlington AN - OPUS4-32819 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -