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Wir haben aufgrund großer Nachfrage unser ACENTISS Academy Kursangebot um nachfolgende Kurse erweitert:
Introduction to Strain Based Fatigue Analysis Large amplitudes of loads might lead to high plastic response in notches. Low cycle fatigue, also in combination with high-cycle fatigue, will require the use of a strain-based concept for analytical durability assessment. This seminar will provide a basic understanding of the strain-based concept. Material data for cyclic loading including the elastic-plastic response of notches will be explained first. Some emphasis will also put on estimating cyclic material data since some of the data might not be easily available. The quality of those estimations will be on focus in a further discussion. Mean stress effects are usually covered by means of damage parameters in the strain based concept. Some simple and some more sophisticated parameters will be presented and their validity discussed. Real components or large structures require the estimation of elastic-plastic notch response. Methods to estimate the load-notch response to speed up the analysis will be another topic in the agenda. Cycle counting and damage accumulation for the strain based concept need to be handled differently to the stress based concept. Best practice methods to count cycles properly will be presented. Introduction to Multiaxial Fatigue Analysis Most structures are prone to local multiaxial stress or strain states. Estimation of durability gets even more difficult, if non-proportional stresses are present. The seminar starts with an introduction to basics of multiaxial fatigue including handling of three dimensional stress or strain states. Transformation of stress states in rotated coordinate systems is necessary to use different multiaxial fatigue theories together with finite element models. In case of low-cycle fatigue, plasticity models are necessary to calculate the multiaxial stress-strain behaviour in notches. Basic understanding of multiaxial plasticity effects, i.e. different effects of hardening, is covered as well. The quality of a very simple plasticity model and an overview about available plasticity models in finite element software will be explained. Estimating multiaxial fatigue data will also be discussed using different examples. Different stress, strain and energy-based parameters for the estimation of damage as well as techniques to handle multiaxial stress-strain behaviour will be introduced. Critical plane, integral methods or incremental fatigue methods will be presented as an overview to give an ideal about the large amount of methods from multiaxial fatigue research. A demonstration on the performance of some selected parameters with respect to multiaxial low cycle problems including the elastic-plastic notch-strain analysis will finish this chapter. Multiaxial fatigue counting requires special methods compared to uniaxial cycle count. Some alternatives will be presented. Examples on multiaxial fatigue as handled in commercial codes will finish up this lecture. Detaillierte Informationen zu allen Kursen entnehmen Sie bitte dem ACENTISS Academy Katalog 2012. |