Masterarbeit multi-axial fatigue assessment

Contribution to the fatigue assessment of power plant components under multi-axial loading conditions including damage accumulation aspects

Fatigue of power plant components can be considered as one of the main ageing mechanisms and has to be addresses by appropriate assessment concepts. Particularly, fatigue assessment under multi-axial loading conditions is a complex subject with permanent need of improvement. The decisive ingredients of a successful and more realistic fatigue lifetime estimation are the choice of appropriate damage parameters and a damage accumulation model with the ability of considering sequence effects and the influence of the transient endurance limit [1-2].   

The work will emanate from a comprehensive literature study including the latest published research results and technical literature standards concerning elasto-plastic fatigue assessment approaches including the design code framework (ASME code) [3-4].

Furthermore, recent results from uniaxial fatigue testing were used to qualify advanced fatigue damage parameters for the successful prediction of damage accumulation effects. The logical next step is the multi-axial formulation of these damage parameters as an essential part of this thesis. In detail, the following damage parameters are to be included in the study: equivalent strain range measures according to on-going international discussion, damage Parameters PSWT (Smith, Watson and Topper), PHL (Haibach-Lehrke original and modified) as well as PJ (short crack fracture mechanics based). The component examples will include an international benchmark problem and a component test sample from an on-going cooperative R&D project including weld seams.

All steps have to be specified and documented. Further proposals for improvement should be made. The final thesis will substantiate the choice of an appropriate multi-axial fatigue assessment model.

[1] Schopf, T.; Weihe, S.; Rudolph, J.: Recent developments of advanced calculation concepts for the fatigue assessment of power plant components.
Proceedings of the ASME 2022 Pressure Vessels & Piping Conference. PVP2022, July 17-22, 2022, Las Vegas, NV, USA, Paper No. 85543

[2] Schopf, T.; Weihe, S.; Rudolph, J.: Investigations on multi-stage tests and transient endurance limit behavior under low-, high- and very high cycle fatigue loads.
Proceedings of the ASME 2022 Pressure Vessels & Piping Conference. PVP2022, July 17-22, 2022, Las Vegas, NV, USA, Paper No. 84718

[3] Matusin, C.S.; Damiani, T.M.: A round robin evaluation of elastic-plastic measures for fatigue analysis.
Proceedings of the ASME 2023 Pressure Vessels & Piping Conference. PVP2023, July 16-21, 2023, Atlanta, Georgia, USA, Paper No. 101728

[4] Damiani, T.M.; Matusin, C.S.: Assessment of fatigue using elastic-plastic analysis in ASME Section III Appendix XIII: A proposed approach and technical justification.
Proceedings of the ASME 2023 Pressure Vessels & Piping Conference. PVP2023

• Studium des Maschinenbaus, der Technischen Mechanik oder der Kraftwerkstechnik
• Abschlussarbeit als Master 

Spécialité : N2 - Etudes - méthodes développement analytique

Niveau d’études (tous) Baccalauréat

Lieu : Allemagne, Bavière - Erlangen, Erlangen