Dokument-ID Dokumenttyp Verfasser/Autoren Herausgeber Haupttitel Abstract Auflage Verlagsort Verlag Erscheinungsjahr Seitenzahl Schriftenreihe Titel Schriftenreihe Bandzahl ISBN Quelle der Hochschulschrift Konferenzname Bemerkung Quelle:Titel Quelle:Jahrgang Quelle:Heftnummer Quelle:Erste Seite Quelle:Letzte Seite URN DOI Zugriffsart Link Abteilungen OPUS4-11083 Wissenschaftlicher Artikel Zhen, Manghao, ; Liang, Yunpei, ; Staat, Manfred, m.staat@fh-aachen.de; Li, Quanqui, ; Li, Jianbo, Discontinuous fracture behaviors and constitutive model of sandstone specimens containing non-parallel prefabricated fissures under uniaxial compression The deformation and damage laws of non-homogeneous irregular structural planes in rocks are the basis for studying the stability of rock engineering. To investigate the damage characteristics of rock containing non-parallel fissures, uniaxial compression tests and numerical simulations were conducted on sandstone specimens containing three non-parallel fissures inclined at 0°, 45° and 90° in this study. The characteristics of crack initiation and crack evolution of fissures with different inclinations were analyzed. A constitutive model for the discontinuous fractures of fissured sandstone was proposed. The results show that the fracture behaviors of fissured sandstone specimens are discontinuous. The stress-strain curves are non-smooth and can be divided into nonlinear crack closure stage, linear elastic stage, plastic stage and brittle failure stage, of which the plastic stage contains discontinuous stress drops. During the uniaxial compression test, the middle or ends of 0° fissures were the first to crack compared to 45° and 90° fissures. The end with small distance between 0° and 45° fissures cracked first, and the end with large distance cracked later. After the final failure, 0° fissures in all specimens were fractured, while 45° and 90° fissures were not necessarily fractured. Numerical simulation results show that the concentration of compressive stress at the tips of 0°, 45° and 90° fissures, as well as the concentration of tensile stress on both sides, decreased with the increase of the inclination angle. A constitutive model for the discontinuous fractures of fissured sandstone specimens was derived by combining the logistic model and damage mechanic theory. This model can well describe the discontinuous drops of stress and agrees well with the whole processes of the stress-strain curves of the fissured sandstone specimens. Amsterdam Elsevier 2024 13 Seiten Theoretical and Applied Fracture Mechanics 131 Art. No. 104373 10.1016/j.tafmec.2024.104373 campus https://doi.org/10.1016/j.tafmec.2024.104373 Fachbereich Medizintechnik und Technomathematik OPUS4-7749 Wissenschaftlicher Artikel Wegmann, Kilian, ; Hackl, Michael, ; Staat, Manfred, m.staat@fh-aachen.de; Mayer, Katharina, ; Müller, Lars-Peter, Double plate osteosynthesis of proximal ulna fractures: biomechanical and clinical results While plate fixation of proximal ulna fractures might lead to superior clinical results compared to tension band wiring, regular plates represent an established risk factor for wound complications. The olecranon double plates (Medartis, Basel, CH) might decrease complications related to the osteosynthesis because of their low profile and better anatomical fit. This study aimed to evaluate the biomechanical performance and clinical results of the olecranon double plates. Berlin Springer 2016 1 Knee surgery, sports traumatology, arthroscopy Volume 24 Supplement 1 58 59 10.1007/s00167-016-4079-0 campus http://doi.org/10.1007/s00167-016-4079-0 Fachbereich Medizintechnik und Technomathematik OPUS4-95 Wissenschaftlicher Artikel Vu, Duc-Khoi, ; Staat, Manfred, m.staat@fh-aachen.de An algorithm for shakedown analysis of structure with temperature dependent yield stress This work is an attempt to answer the question: How to use convex programming in shakedown analysis of structures made of materials with temperature-dependent properties. Based on recently established shakedown theorems and formulations, a dual relationship between upper and lower bounds of the shakedown limit load is found, an algorithmfor shakedown analysis is proposed. While the original problem is neither convex nor concave, the algorithm presented here has the advantage of employing convex programming tools. 2004 Fachbereich Medizintechnik und Technomathematik OPUS4-2798 Wissenschaftlicher Artikel Vu, Duc Khoi, ; Staat, Manfred, m.staat@fh-aachen.de; Tran, Ich Thinh, Analysis of pressure equipment by application of the primal-dual theory of shakedown 2007 12 Communications in Numerical Methods in Engineering. 23 (2007), H. 3 1069-8299 213 225 campus http://dx.doi.org/10.1002/cnm.891 Fachbereich Medizintechnik und Technomathematik OPUS4-2805 Wissenschaftlicher Artikel Vu, Duc Khoi, ; Staat, Manfred, m.staat@fh-aachen.de Shakedown analysis of structures made of materials with temperature-dependent yield stress 2007 16 International Journal of Solids and Structures. 44 (2007), H. 13 0020-7683 4524 4540 campus http://dx.doi.org/10.1016/j.ijsolstr.2006.11.038 Fachbereich Medizintechnik und Technomathematik OPUS4-3459 Wissenschaftlicher Artikel Vant, Christianne, ; Staat, Manfred, m.staat@fh-aachen.de; Baroud, Gamal, Percutaneous Vertebroplasty: A Review of Two Intraoperative Complications Berlin Springer 2008 12 Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.) 978-3-540-75408-4 527 539 bezahl http://dx.doi.org/10.1007/978-3-540-75409-1_22 Fachbereich Medizintechnik und Technomathematik OPUS4-3966 Wissenschaftlicher Artikel Ullrich, Sebastian, ; Grottke, Oliver, ; Rossaint, Rolf, ; Staat, Manfred, m.staat@fh-aachen.de; Deserno, Thomas M., ; Kuhlen, Torsten, Virtual Needle Simulation with Haptics for Regional Anaesthesia 2010 2 IEEE Virtual Reality 2010, Workshop on Medical Virtual Environments, Waltham, MA, USA, March 21, 2010 1 3 weltweit http://www.hpv.cs.bangor.ac.uk/vr10-med/Papers/Ullrich-VirtualNeedleSimulation.pdf Fachbereich Medizintechnik und Technomathematik OPUS4-191 Konferenzveröffentlichung Tran, Thanh Ngoc, tran@fh-aachen.de; Staat, Manfred, m.staat@fh-aachen.de; Kreißig, R., Calculation of load carrying capacity of shell structures with elasto-plastic material by direct methods Proceedings of the International Conference on Material Theory and Nonlinear Dynamics. MatDyn. Hanoi, Vietnam, Sept. 24-26, 2007, 8 p. In this paper, a method is introduced to determine the limit load of general shells using the finite element method. The method is based on an upper bound limit and shakedown analysis with elastic-perfectly plastic material model. A non-linear constrained optimisation problem is solved by using Newton's method in conjunction with a penalty method and the Lagrangean dual method. Numerical investigation of a pipe bend subjected to bending moments proves the effectiveness of the algorithm. 2007 Fachbereich Medizintechnik und Technomathematik OPUS4-196 Konferenzveröffentlichung Tran, Thanh Ngoc, tran@fh-aachen.de; Staat, Manfred, m.staat@fh-aachen.de; Kreißig, R., Finite element shakedown and limit reliability analysis of thin shells A procedure for the evaluation of the failure probability of elastic-plastic thin shell structures is presented. The procedure involves a deterministic limit and shakedown analysis for each probabilistic iteration which is based on the kinematical approach and the use the exact Ilyushin yield surface. Based on a direct definition of the limit state function, the non-linear problems may be efficiently solved by using the First and Second Order Reliabiblity Methods (Form/SORM). This direct approach reduces considerably the necessary knowledge of uncertain technological input data, computing costs and the numerical error. In: Computational plasticity / ed. by Eugenio Onate. Dordrecht: Springer 2007. VII, 265 S. (Computational Methods in Applied Sciences ; 7) (COMPLAS IX. Part 1 . International Center for Numerical Methods in Engineering (CIMNE)). ISBN 978-1-402-06576-7 S. 186-189 2007 Fachbereich Medizintechnik und Technomathematik OPUS4-3995 Wissenschaftlicher Artikel Tran, Thanh Ngoc, tran@fh-aachen.de; Staat, Manfred, m.staat@fh-aachen.de Shakedown analysis of two dimensional structures by an edge-based smoothed finite element method 2010 6 ECCM 2010, IV European Conference on Computational Mechanics, Paris, France, May 16-21, 2010. 1 7 weltweit http://www.eccm2010.org/complet/fullpaper_1042.pdf Fachbereich Medizintechnik und Technomathematik