@misc{Staat2006, author = {Staat, Manfred}, title = {Technische Mechanik. Vorlesungsmitschrift. Korrigierter Nachdr. der 3. Aufl.}, year = {2006}, abstract = {{\"U}berarbeitete, korrigierte und erg{\"a}nzte Version einer Vorlesungsmitschrift von Sebastian Kr{\"a}mer. 172 S. Inhaltsverzeichnis 0 Einf{\"u}hrung in die Mechanik 1 Statik starrer K{\"o}rper 2 Elastostatik (Festigkeitslehre) 3 Kinematik 4 Kinetik Literatur}, subject = {Technische Mechanik}, language = {de} } @misc{Staat2006, author = {Staat, Manfred}, title = {Engineering Mechanics. Lecture Notes. 2nd edition, translation of the 3rd corrected and extended German edition of "Technische Mechanik"}, year = {2006}, abstract = {English translation of the corrected lectures notes of Sebastian Kr{\"a}mer. Contents 0 Introduction to Mechanics 1 Statics of Rigid Bodies 2 Elastostatics (Strength of Materials) 3 Kinematics 4 Kinetics Literature}, subject = {Technische Mechanik}, language = {en} } @inproceedings{Staat2006, author = {Staat, Manfred}, title = {Problems and chances for probabilistic fracture mechanics in the analysis of steel pressure boundary reliability. - {\"U}berarb. Ausg.}, year = {2006}, abstract = {In: Technical feasibility and reliability of passive safety systems for nuclear power plants. Proceedings of an Advisory Group Meeting held in J{\"u}lich, 21-24 November 1994. - Vienna , 1996. - Seite: 43 - 55 IAEA-TECDOC-920 Abstract: It is shown that the difficulty for probabilistic fracture mechanics (PFM) is the general problem of the high reliability of a small population. There is no way around the problem as yet. Therefore what PFM can contribute to the reliability of steel pressure boundaries is demon­strated with the example of a typical reactor pressure vessel and critically discussed. Although no method is distinguishable that could give exact failure probabilities, PFM has several addi­tional chances. Upper limits for failure probability may be obtained together with trends for design and operating conditions. Further, PFM can identify the most sensitive parameters, improved control of which would increase reliability. Thus PFM should play a vital role in the analysis of steel pressure boundaries despite all shortcomings.}, subject = {Bruchmechanik}, language = {en} } @article{Staat2021, author = {Staat, Manfred}, title = {An extension strain type Mohr-Coulomb criterion}, series = {Rock mechanics and rock engineering}, volume = {54}, journal = {Rock mechanics and rock engineering}, number = {12}, publisher = {Springer Nature}, address = {Cham}, issn = {1434-453X}, doi = {10.1007/s00603-021-02608-7}, pages = {6207 -- 6233}, year = {2021}, abstract = {Extension fractures are typical for the deformation under low or no confining pressure. They can be explained by a phenomenological extension strain failure criterion. In the past, a simple empirical criterion for fracture initiation in brittle rock has been developed. In this article, it is shown that the simple extension strain criterion makes unrealistic strength predictions in biaxial compression and tension. To overcome this major limitation, a new extension strain criterion is proposed by adding a weighted principal shear component to the simple criterion. The shear weight is chosen, such that the enriched extension strain criterion represents the same failure surface as the Mohr-Coulomb (MC) criterion. Thus, the MC criterion has been derived as an extension strain criterion predicting extension failure modes, which are unexpected in the classical understanding of the failure of cohesive-frictional materials. In progressive damage of rock, the most likely fracture direction is orthogonal to the maximum extension strain leading to dilatancy. The enriched extension strain criterion is proposed as a threshold surface for crack initiation CI and crack damage CD and as a failure surface at peak stress CP. Different from compressive loading, tensile loading requires only a limited number of critical cracks to cause failure. Therefore, for tensile stresses, the failure criteria must be modified somehow, possibly by a cut-off corresponding to the CI stress. Examples show that the enriched extension strain criterion predicts much lower volumes of damaged rock mass compared to the simple extension strain criterion.}, language = {en} } @article{LeversStaatLaack2011, author = {Levers, A. and Staat, Manfred and Laack, Walter van}, title = {Analyse der Langzeitwirkung der MBST® KernspinResonanzTherapie bei Gonarthrose}, year = {2011}, abstract = {Originalausgabe: Orthop{\"a}dische Praxis Jg. 47. 2011 H. 11; S. 536-543. Mit freundlicher Genehmigung des Verlags Zusammenfassung: Auf der Basis von Patientenabfragen mittels Fragebogen zum Schmerzempfinden und zur Einschr{\"a}nkung bei Aktivit{\"a}ten des allt{\"a}glichen Lebens wird die Langzeitwirkung der MBST® KernspinResonanz-Therapie bei Gonarthrose untersucht. An der Studie nahmen 39 Patienten teil, bei denen die Therapie bis zu vier Jahre zur{\"u}ckliegt. Neben einer Gesamtbetrachtung wird der Erfolg auch in Abh{\"a}ngigkeit von Alter, Geschlecht und sportlicher Aktivit{\"a}t analysiert. Insgesamt weist die Studie auf eine anhaltende Verbesserung des Gesundheitszustands mit zum Teil deutlicher Schmerzlinderung auch noch nach vier Jahren hin, jedoch mit einer leichten Schmerzzunahme gegen Ende des Untersuchungszeitraums von vier Jahren. Eine tendenziell positivere Wirkung bei Frauen, {\"a}lteren Menschen oder auch sportlich nicht-aktiven Patienten l{\"a}sst auf eine m{\"o}gliche Beeinflussung des Erfolgs der Therapie durch ({\"U}ber-)Belastung im Alltag schließen. Ein zus{\"a}tzlich positiver Effekt der Therapie auf die Knochendichte ist ebenfalls denkbar, dies bleibt jedoch offen.}, subject = {Kniegelenkarthrose}, language = {de} } @inproceedings{LangWirtzHeitzeretal.1999, author = {Lang, H. and Wirtz, K. and Heitzer, Michael and Staat, Manfred and Oettel, R.}, title = {Zyklische Einspielversuche zur Verifikation von Shakedown-Analysen mittels FEM}, year = {1999}, abstract = {Im Rahmen von Erm{\"u}dungsanalysen ist nachzuweisen, daß die thermisch bedingten fortschreitenden Deformationen begrenzt bleiben. Hierzu ist die Abgrenzung des Shakedown-Bereiches (Einspielen) vom Ratchetting-Bereich (fortschreitende Deformation) von Interesse. Im Rahmen eines EU-gef{\"o}rderten Forschungsvorhabens wurden Experimente mit einem 4-Stab-Modell durchgef{\"u}hrt. Das Experiment bestand aus einem wassergek{\"u}hlten inneren Rohr und drei isolierten und beheizbaren {\"a}ußeren Probest{\"a}ben. Das System wurde durch alternierende Axialkr{\"a}fte, denen alternierende Temperaturen an den {\"a}ußeren St{\"a}ben {\"u}berlagert wurden, belastet. Die Versuchsparameter wurden teilweise nach vorausgegangenen Einspielanalysen gew{\"a}hlt. W{\"a}hrend der Versuchsdurchf{\"u}hrung wurden Temperaturen und Dehnungen zeitabh{\"a}ngig gemessen. Begleitend und nachfolgend zur Versuchsdurchf{\"u}hrung wurden die Belastungen und die daraus resultierenden Beanspruchungen nachvollzogen. Bei dieser inkrementellen elasto-plastischen Analyse mit dem Programm ANSYS wurden unterschiedliche Werkstoffmodelle angesetzt. Die Ergebnisse dieser Simulationsberechnung dienen dazu, die Shakedown-Analysen mittels FE-Methode zu verifizieren.}, subject = {Einspielen }, language = {de} } @article{KuehnHaugnerStaatetal.2004, author = {K{\"u}hn, Raoul-Roman and Haugner, Werner and Staat, Manfred and Sponagel, Stefan}, title = {A Two Phase Mixture Model based on Bone Observation}, year = {2004}, abstract = {An optimization method is developed to describe the mechanical behaviour of the human cancellous bone. The method is based on a mixture theory. A careful observation of the behaviour of the bone material leads to the hypothesis that the bone density is controlled by the principal stress trajectories (Wolff's law). The basic idea of the developed method is the coupling of a scalar value via an eigenvalue problem to the principal stress trajectories. On the one hand this theory will permit a prediction of the reaction of the biological bone structure after the implantation of a prosthesis, on the other hand it may be useful in engineering optimization problems. An analytical example shows its efficiency.}, subject = {Knochen}, language = {en} } @inproceedings{JungStaatMueller2014, author = {Jung, Alexander and Staat, Manfred and M{\"u}ller, Wolfram}, title = {Optimization of the flight style in ski jumping}, series = {11th World Congress on Computational Mechanics (WCCM XI) ; 5th European Conference on Computational Mechanics (ECCM V) ; 6th European Conference on Computational Fluid Dynamics (ECFD VI) ; July 20 - 25, 2014, Barcelona}, booktitle = {11th World Congress on Computational Mechanics (WCCM XI) ; 5th European Conference on Computational Mechanics (ECCM V) ; 6th European Conference on Computational Fluid Dynamics (ECFD VI) ; July 20 - 25, 2014, Barcelona}, editor = {Onate, E.}, organization = {World Congress on Computational Mechanics <11, 2014, Barcelona>}, pages = {799 -- 810}, year = {2014}, language = {en} } @inproceedings{JungFrotscherStaat2018, author = {Jung, Alexander and Frotscher, Ralf and Staat, Manfred}, title = {Electromechanical model of hiPSC-derived ventricular cardiomyocytes cocultured with fibroblasts}, series = {6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK}, booktitle = {6th European Conference on Computational Mechanics (ECCM 6), 7th European Conference on Computational Fluid Dynamics (ECFD 7), 11-15 June 2018, Glasgow, UK}, pages = {11 Seiten}, year = {2018}, abstract = {The CellDrum provides an experimental setup to study the mechanical effects of fibroblasts co-cultured with hiPSC-derived ventricular cardiomyocytes. Multi-scale computational models based on the Finite Element Method are developed. Coupled electrical cardiomyocyte-fibroblast models (cell level) are embedded into reaction-diffusion equations (tissue level) which compute the propagation of the action potential in the cardiac tissue. Electromechanical coupling is realised by an excitation-contraction model (cell level) and the active stress arising during contraction is added to the passive stress in the force balance, which determines the tissue displacement (tissue level). Tissue parameters in the model can be identified experimentally to the specific sample.}, language = {en} } @inproceedings{HeitzerStaat2000, author = {Heitzer, M. and Staat, Manfred}, title = {Direct FEM approach to design-by-analysis of pressurized components}, year = {2000}, abstract = {Abstracts of the ACHEMA 2000 - International Meeting on Chemical Engineering, Environmental Protection and Biotechnology, May 22 - 27, 2000. Frankfurt am Main. Achema 2000 : special edition / Linde. [Ed.: Linde AG. Red.: Volker R. Leski]. - Wiesbaden : Linde AG, 2000. - 56 p. : Ill., . - pp: 79 - 81}, subject = {Finite-Elemente-Methode}, language = {en} }