TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Limit and Shakedown Analysis with Uncertain Data JF - Stochastic optimization techniques : numerical methods and technical applications / Marti, K. [ed] Y1 - 2002 SN - 3-540-42889-5 SP - 241 EP - 254 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Staat, Manfred T1 - Cyclic plastic deformation tests to verify FEM-based shakedown analyses N2 - Fatigue analyses are conducted with the aim of verifying that thermal ratcheting is limited. To this end it is important to make a clear distintion between the shakedown range and the ratcheting range (continuing deformation). As part of an EU-supported research project, experiments were carried out using a 4-bar model. The experiment comprised a water-cooled internal tube, and three insulated heatable outer test bars. The system was subjected to alternating axial forces, superimposed with alternating temperatures at the outer bars. The test parameters were partly selected on the basis of previous shakedown analyses. During the test, temperatures and strains were measured as a function of time. The loads and the resulting stresses were confirmed on an ongoing basis during performance of the test, and after it. Different material models were applied for this incremental elasto-plastic analysis using the ANSYS program. The results of the simulation are used to verify the FEM-based shakedown analysis. KW - Materialermüdung KW - Einspielen KW - Materialermüdung KW - shakedown analyses KW - thermal ratcheting KW - fatigue analyses Y1 - 2001 ER - TY - JOUR A1 - Staat, Manfred T1 - LISA - a European project for FEM-based limit and shakedown analysis N2 - The load-carrying capacity or the safety against plastic limit states are the central questions in the design of structures and passive components in the apparatus engineering. A precise answer is most simply given by limit and shakedown analysis. These methods can be based on static and kinematic theorems for lower and upper bound analysis. Both may be formulated as optimization problems for finite element discretizations of structures. The problems of large-scale analysis and the extension towards realistic material modelling will be solved in a European research project. Limit and shakedown analyses are briefly demonstrated with illustrative examples. KW - Einspielen KW - Traglast KW - Finite-Elemente-Methode KW - Traglastanalyse KW - Einspielanalyse KW - FEM KW - limit analysis KW - shakedown analysis Y1 - 2001 ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Traglastanalyse - ein strukturmechanisches Verfahren zur Beurteilung von gerissenen Bauteilen und Verbindungen JF - Festigkeits- und Bruchverhalten von Fügeverbindungen : 32. Tagung des DVM-Arbeitskreises Bruchvorgänge ; 22. und 23. Februar 2000 in Berlin / Richard, H. A. [Hrsg] Y1 - 2000 N1 - DVM-Bericht 232 SP - 183 EP - 192 PB - Deutscher Verband für Materialforschung und -prüfung CY - Berlin ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Reliability Analysis of Elasto-Plastic Structures under Variable Loads JF - Inelastic analysis of structures under variable loads : theory and engineering applications / Maier, G.; Weichert, D. [ed] Y1 - 2000 SN - 0-7923-6645-X SP - 269 EP - 288 PB - Kluwer Academic Publ. CY - Dordrecht ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Direct FEM approach to design-by-analysis of pressurized components JF - Achema 2000 : Sonderausgabe / Linde. [Hrsg.: Linde AG. Red.: Volker R. Leski] Y1 - 2000 SP - 79 EP - 81 PB - Linde AG CY - Wiesbaden ER - TY - JOUR A1 - Staat, Manfred T1 - Basis Reduction for the Shakedown Problem for Bounded Kinematic Hardening Material N2 - Limit and shakedown analysis are effective methods for assessing the load carrying capacity of a given structure. The elasto–plastic behavior of the structure subjected to loads varying in a given load domain is characterized by the shakedown load factor, defined as the maximum factor which satisfies the sufficient conditions stated in the corresponding static shakedown theorem. The finite element dicretization of the problem may lead to very large convex optimization. For the effective solution a basis reduction method has been developed that makes use of the special problem structure for perfectly plastic material. The paper proposes a modified basis reduction method for direct application to the two-surface plasticity model of bounded kinematic hardening material. The considered numerical examples show an enlargement of the load carrying capacity due to bounded hardening. KW - Finite-Elemente-Methode KW - Einspielen KW - Basis Reduktion KW - konvexe Optimierung KW - FEM KW - Druckgeräte KW - Basis reduction KW - Convex optimization KW - FEM KW - Shakedown analysis Y1 - 2000 ER - TY - JOUR A1 - Staat, Manfred T1 - Direct FEM Limit and Shakedown Analysis with Uncertain Data N2 - The structural reliability with respect to plastic collapse or to inadaptation is formulated on the basis of the lower bound limit and shakedown theorems. A direct definition of the limit state function is achieved which permits the use of the highly effective first order reliability methods (FORM) is achieved. The theorems are implemented into a general purpose FEM program in a way capable of large-scale analysis. The limit state function and its gradient are obtained from a mathematical optimization problem. This direct approach reduces considerably the necessary knowledge of uncertain technological input data, the computing time, and the numerical error, leading to highly effective and precise reliability analyses. KW - Finite-Elemente-Methode KW - Einspielen KW - FEM KW - Einspielanalyse KW - shakedown KW - limit load KW - reliability analysis KW - FEM KW - direct method Y1 - 2000 ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Structural Reliability Analysis of Elasto-Plastic Structures JF - Safety and reliability : proceedings of ESREL '99, the Tenth European Conference on Safety and Reliability, Munich-Garching, Germany, 13 - 17 September 1999 / Schuëller, G. I.; Kafka, P. [eds] Y1 - 1999 SN - 90-5809-109-0 SP - 513 EP - 518 PB - Balkema CY - Rotterdam ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - FEM-computation of load carrying capacity of highly loaded passive components by direct methods. Heitzer, M. ; Staat, M. JF - Nuclear Engineering and Design. 193 (1999), H. 3 Y1 - 1999 SN - 0029-5493 SP - 349 EP - 358 ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. A1 - Hicken, E.F. T1 - LISA, ein europäisches Projekt zur direkten Berechnung der Tragfähigkeit duktiler Strukturen. Y1 - 1998 N1 - PERMAS–Benutzertagung, 8.–9.10.1998, Stuttgart (1998) ER - TY - JOUR A1 - Staat, Manfred A1 - Fiorini, G. L. A1 - Lensa, W. von A1 - Burgazzi, L. T1 - Reliability Methods for Passive Safety Functions JF - Proceedings of the SMiRT 14 Post Conference Seminar No 18 on Passive Safety Features in Nuclear Installations Y1 - 1997 CY - Pisa ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Limit and Shakedown Analysis for Plastic Safety of Complex Structures JF - Transactions of the 14th International Conference on Structural Dynamics in Reactor Technology (SMiRT-14) / Livolant, M. [ed] Y1 - 1997 N1 - Vol. B, Paper B02/2 SP - 33 EP - 40 CY - Lyon ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Limit and Shakedown Analysis Using a General Purpose Finite Element Code JF - Proceedings of NAFEMS World Congress '97 on Design, Simulation & Optimisation : reliability & applicability of computational methods ; Stuttgart, Germany, 9 - 11 April 1997 Y1 - 1997 SN - 1-87437-620-4 SP - 522 EP - 533 PB - NAFEMS CY - Glasgow ER - TY - JOUR A1 - Staat, Manfred T1 - Problems and Chances for Probabilistic Fracture Mechanics in the Analysis of Steel Pressure Boundary Reliability JF - Technical feasibility and reliability of passive safety systems for nuclear power plants. Proceedings of an Advisory Group Meeting held in Jülich, 21-24 November 1994 Y1 - 1996 N1 - IAEA-TECDOC-920 ; Onlinezugriff erfolgt auf die überarb. Ausg. 2006 SP - 43 EP - 55 CY - Vienna ER - TY - JOUR A1 - Staat, Manfred T1 - Probabilistic assessment of the fracture mechanics behaviour of an HTR-module primary circuit pressure boundary JF - Nuclear Engineering and Design. 160 (1996), H. 1-2 Y1 - 1996 SN - 0029-5493 SP - 221 EP - 236 ER - TY - JOUR A1 - Staat, Manfred T1 - Reliability of an HTR-module primary circuit pressure boundary Influences, sensitivity, and comparison with a PWR JF - Nuclear Engineering and Design. 158 (1995), H. 2-3 Y1 - 1995 SN - 0029-5493 SP - 333 EP - 340 ER - TY - JOUR A1 - Staat, Manfred T1 - Sensitivity of and Influences on the Reliability of an HTR-Module Primary Circuit Pressure Boundary JF - Transactions of the 12th International Conference on Structural Mechanics in Reactor Technology (SMiRT-12) / Kussmaul, K. [ed] Y1 - 1993 SN - 0-444-81515-5 N1 - Vol. M, Paper MG10/2 SP - 147 EP - 152 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Staat, Manfred T1 - Reliability of the Primary Circuit Pressure Boundary of an HTR-Module under Accident Conditions JF - Safety and reliability assessment : an integral approach ; ESREL'93 ; proceedings of the European Safety and Reliability Conference, Munich, Germany, May 10th - 12th 1993 / Kafka, P. [ed] Y1 - 1993 SN - 0-444-81561-9 SP - 331 EP - 342 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Staat, Manfred T1 - Failure probabilities of the primary circuit pressure boundary of an HTR-Module for process heat generation under accident conditions for different failure modes JF - Nuclear Engineering and Design. 144 (1993), H. 1 Y1 - 1993 SN - 0029-5493 SP - 53 EP - 67 ER - TY - JOUR A1 - Staat, Manfred T1 - Probabilistische Bewertung des bruchmechanischen Verhaltens der Primärkreisdruckumschließung eines HTR-Moduls Y1 - 1992 N1 - 18. MPA-Seminar : Sicherheit und Verfügbarkeit in der Anlagentechnik mit dem Schwerpunkt Kernenergie. Stuttgart (1992), 27.1-27.18 ER - TY - JOUR A1 - Staat, Manfred T1 - Versagenswahrscheinlichkeit der Primärkreisdruckumschließung eines HTR-Moduls zur Prozeßwärmegewinnung unter Störfallbedingungen bei verschiedenen Versagensmoden Y1 - 1991 N1 - 17. MPA-Seminar : Sicherheit und Verfügbarkeit in der Anlagentechnik mit dem Schwerpunkt Kerntechnik, Stuttgart (1991), 22.1-22.20 ER - TY - JOUR A1 - Staat, Manfred T1 - Versagenswahrscheinlichkeit der Primärkreisdruckumschließung eines HTR-Moduls zur Prozeßwärmegewinnung unter Störfallbedingungen JF - Jahrestagung Kerntechnik '91 / Kerntechnische Gesellschaft e.V. ; Deutsches Atomforum e.V Y1 - 1991 SP - 123 EP - 126 PB - INFORUM CY - Bonn ER - TY - JOUR A1 - Staat, Manfred A1 - Wolters, J A1 - Bongarts, W. A1 - Hennings, W. (u.a.) T1 - Überarbeitete probabilistisch orientierte Sicherheitsanalyse für den HTR-Modul JF - Jahrestagung Kerntechnik '90 / Kerntechnische Gesellschaft e.V. ; Deutsches Atomforum e.V Y1 - 1990 SP - 143 EP - 146 PB - INFORUM CY - Bonn ER - TY - JOUR A1 - Staat, Manfred A1 - Ballmann, J. T1 - Zur Problematik tensorieller Verallgemeinerungen einachsiger nichtlinearer Materialgesetze JF - Zeitschrift für angewandte Mathematik und Mechanik : ZAMM. 69 (1989), H. 2 Y1 - 1989 SN - 0946-8463 U6 - http://dx.doi.org/10.1515/9783112553169-006 SP - 73 EP - 81 ER - TY - JOUR A1 - Staat, Manfred A1 - Ballmann, J. T1 - Computation of impacts on elastic solids by methods of bicharacteristics JF - Computational Mechanics '88 : theory and applications ; proceedings of the International Conference on Computational Engineering Science April 10-14, 1988, Atlanta, GA, USA ; vol. 2 N2 - Shock waves, explosions, impacts or cavitation bubble collapses may generate stress waves in solids causing cracks or unexpected dammage due to focussing, physical nonlinearity or interaction with existing cracks. There is a growing interest in wave propagation, which poses many novel problems to experimentalists and theorists. KW - Bicharakteristikenverfahren KW - Elastizität KW - elastic solids KW - bicharacteristics Y1 - 1988 SP - 1719 EP - 1722 ER - TY - JOUR A1 - Staat, Manfred A1 - Ballmann, J. T1 - Wave Propagation and Focussing in Plates JF - Impact loading and dynamic behaviour of materials : Papers presented at the International Conference on Impact Loading and Dynamic Behaviour of Materials, Vol. 2 / Chiem, C. Y.; Kunze, L. (u.a.) [eds] Y1 - 1988 PB - DGM Informationsges. CY - Oberursel ER - TY - JOUR A1 - Staat, Manfred T1 - Anisotrope Wellenausbreitung in isotropen hyperelastischen Scheiben JF - Zeitschrift für angewandte Mathematik und Mechanik : ZAMM. 67 (1987), H. 4 Y1 - 1987 SN - 0946-8463 SP - T241 EP - T243 ER - TY - JOUR A1 - Staat, Manfred A1 - Ballmann, J. T1 - Anisotrope Ausbreitung und Fokussierung von Beschleunigungswellen in vorgespannten nichtlinearelastischen Scheiben JF - Wellenfokussierung, Kolloquium des SFB 27, RWTH Aachen Y1 - 1985 SP - 140 EP - 158 CY - Aachen ER -