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Relevance of the work. Estimation of the stability of free face is an important task due to the fact that part of headings of tube railroad is erected by mining, with the forehead of the face fixed manually, while indirect methods of forecasting engineering-geological and hydrogeological conditions before the forehead of the face indicate the presence of local softening and watering capable affect sustainability. Purpose of the work. Estimation of the zone of influence and the type of drainage of the element of heterogeneity on the stability of the tunnel face passed in the array of Proterozoic clays. Method and methodology. The finite element method used in the PLAXIS software package was chosen as the research method. The Hardening Soil Small Strain hardening soil model was selected as a geomechanical model of soil behavior. The design situations of deforming the unfixed forehead of the face approaching the water-saturated element of heterogeneity, are considered when simulating an element with a capacity of 1 and 4 m and changing the nature of water filtration along the element. Results of the work. When deformation properties of the calculated soil elements differ by 30% with the given level of groundwater, both in the case of drainage and nondrainability, an increase in displacements occurs when the tunneling face approaches the zone of influence of heterogeneity. The size of the zone of influence depends on the chosen type of drainage of the element of heterogeneity. Applicable scope of the results described in the paper. The results described in the paper (subject to determining the parameters of the model that meet the conditions of penetration) can be used to estimate the stability of the forehead of the tunnel face in the area of heterogeneity, which is the water supply canal. Conclusion. When designing construction of a linear underground facility in an area of heterogeneity, it is necessary to evaluate the stability of the forehead of the face using numerical modeling. When modeling an element of heterogeneity, it is necessary to take into account the degree of water saturation, the thickness of the element of heterogeneity and the nature of permeability of water along the element of heterogeneity.

Diese Arbeit beschäftigt sich mit einer Thematik aus dem Erd- und Wasserbau, den sogenannten Dalbenkonstruktionen. Dalben sind Bauwerke (meist Einzelpfähle oder Pfahlgruppen), die zum Anlegen und Verheften von Schiffen im Hafen dienen. Neben der Anlege- und Vertäufunktion am Uferbauwerk können Dalben vielseitig angewendet werden. Sie können als Schutz-, Leit-, Streich-, Leuchtfeuer-, Eisbrecher-, Führungs- und Deviationsdalben konstruiert werden. Im Rahmen dieser Arbeit wird der Begriff „Dalben“ näher erläutert und auf die verschiedenen Konstruktionsarten der Wasserbaukonstruktionen eingegangen. Ergänzend dazu wird der Ansatz zur Bemessung von Dalben anhand der Zusammenhänge zur Spundwandberechnung hergeleitet. Im Folgenden wird die Dimensionierung von Dalben genau beschrieben und die Berechnungsansätze vorgestellt. Dabei werden die nach dem heutigen Stand der Technik am häufigsten verwendeten Berechnungsmethoden erklärt. Dabei wird der Bemessungsansatz nach Blum der Bemessung nach dem nicht-linearen Bettungsmodulverfahren mittels P-y-Kurven gegenübergestellt. Der Vergleich wird anhand von praktischen Berechnungsbeispielen erklärt. Die Ergebnisse sollen außerdem Erkenntnisse über die Anwendbarkeit dieser Methoden liefern. This paper deals with a topic in the area of geotechnical and hydraulic engineering, the mooring piles. Mooring piles are structures (either made of one single pile or a bond of piles) which are mainly used to moor ships on harbors. In addition to the mooring function on the bank structure mooring piles can be used in many ways. They can be constructed as protection-, guide-, strike-, beacon-, icebreaker-, lead-, and deviation piles. During the paper the term mooring pile is going to be defined particularly and the different types of the construction are going to be mentioned and explained. Furthermore, the approach to the design of mooring piles is derived from the relationships to the sheet pile calculation. In the following, the dimensioning of mooring piles will be described in detail and the calculation approaches will be presented. Thereby, the two most pervasive methods, firstly according to the method of Blum and secondly according to the p-y-methodology, are going to be described and compared .The comparison will be made by dimension examples of a mooring pile. The results of the calculations should give information about the practicability of the methods.

Rural depopulation resulting in altered hospital coverage, new challenges for medical evacuation during military operations, and increased off-shore activities of energy suppliers, lead to changed requirements of helicopter emergency medical services (HEMS). Recently, interest has significantly increased to overcome the traditional physical limitation of flight speed by providing helicopters with auxiliary propulsive devices, so-called compound rotorcraft. In order to assess these novel rotorcraft concepts, an integrated, multidisciplinary, and automated design procedure has been established at the German Aerospace Center (DLR) using the data model CPACS (Common Parametric Aircraft Configuration Schema). The design processes of rotary- and fixed-wing aircraft highly resemble each other: In the first stage of a typical aircraft design process, the conceptual stage, basic characteristics are established that typically consist of e.g. outer dimensions (i.e. its aerodynamic shape), flight performance, mass breakdown, etc. At this stage of the design process mostly fast, analytical, and statistical methods are applied featuring many simplifications. In the subsequent preliminary design phase the detail level increases. The continuously growing computational power has enabled design engineers to integrate higher fidelity methods at this design stage. At the DLR Institute of Structures and Design, tools have been developed in the last couple of years that use finite element (FE) methods to size aeronautical fuselage structures according to static load cases to allow a more precise prediction of the structural mass, and thus in turn to a different maximum take-off mass which is considered as a major design parameter. Although based on the same framework approach, these FE based tools developed for preliminary sizing of rotary- and fixed-wing fuselages diverged over the years due to different project requirements, such as specific modeling aspects, different syntax for the involved FE solvers, or different design emphases. These issues resulted in different tools to generate FE meshes and to conduct analyses with some inconsistencies between the individual tools. In order to unify the tools, the development of the software framework PANDORA (Parametric Numerical Design and Optimization Routines for Aircraft) has been started at DLR in 2016 from scratch using the Python programming language. The key idea behind PANDORA is to generate one common software framework to model, analyze, and size both fixed- and rotary-wing fuselage structures. Particular focus in the development of PANDORA lies in the use of dedicated open-source packages and the interchangeability of different commercial and open-source FE solvers. This paper first shows the approach of the PANDORA toolbox for fixed-wing aircraft. Then, the process of adapting respectively integrating specific modeling and analysis methods for rotorcraft fuselages into the new framework is shown. Concluding this article an outlook of new enhancements into PANDORA is given highlighting its benefits in the context of preliminary structural analysis of novel rotorcraft concepts.

Summary Moulded Case Circuit Breaker (MCCB) is a protective device used for low voltage protection in the range of 12–1250 A. It is having fast breaking and making ability due to special contact structure. In case of transformer it is generally placed in secondary side and in case of motor protection it is used as backup protection. The existing design is suffering from chattering of contact tip which lead to erosion and in turn affect electrical life. It also reduces interrupting/breaking capacity of MCCB. In this paper, detailed study of the factors and constraints related to repulsion threshold current ( I rp ) and consistency of magnetic release for 630 A MCCB is carried out using Finite Element tool JMAG to find out limitations and scope of design improvements in existing design. The proposed suggestion is validated by testing.

Diese Arbeit beschäftigt sich mit Kopfplattenstößen und deren Berechnungsmöglichkei-ten. Kopfplattenstöße sind gängige Verbindungsmethoden im Stahlbau bei H- oder I Profilen. Diese Verbindungen bestehen aus mehreren Einzelkomponenten, den Schrau-ben, den Schweißnähten und der Kopfplatte selbst. Die üblichen Berechnungsmethoden gelten nur in bestimmten Situationen, nämlich nur bei Beanspruchungen mit den Schnittgrößen Normalkraft N, Querkraft Vz und Biegemoment My. Treten andere Belastungen auf, liefern die Normen keine Regelungen zur Berechnung. Bei räumlichen Tragwerkssystemen ist es jedoch oft möglich, dass alle sechs Schnittkräfte in den Trägern auftreten können. Bei Beanspruchungen mit den Schnittgrößen Querkraft Vy, Torsionsmoment MT oder Biegemoment Mz bleibt für die Berechnung oft nur die Möglichkeit der Finite-Elemente-Methode (FEM) mit einer geeigneten Computersoftware. In dieser Masterarbeit werden die üblichen Berechnungsmodelle aus dem Euro-code 3 erläutert. Außerdem werden die Tabellen der Typisierten Anschlüsse im Stahlhochbau nach DIN EN 1993-1-8 (den sogenannten DSTV-Stößen des Deutschen Stahlbau-Verbands) und deren Anwendung erklärt. Im Rahmen dieser Arbeit wird ein möglicher Berechnungsansatz für Kopfplat-tenstöße mit sechs Schnittkräften erläutert. Bei diesem Ansatz werden die Schnittkräfte auf ein Äquivalent anderer Schnittkräfte umgerechnet, um eine Be-rechnung mit den gültigen Methoden aus der Norm zu ermöglichen. Außerdem wird diese Berechnungsmethode mit der Standardsoftware Microsoft Office Excel nachprogrammiert um ein praktisches und zugleich günstiges Be-rechnungstool zu schaffen. Dieses Berechnungstool soll einfach in der Bedie-nung sein und schnelle Ergebnisse liefern können. Zuletzt werden die Ergebnisse dieser Berechnungsmethode im speziellen durch das Excel-Berechnungstool mit den Ergebnissen anderer Berechnungen vergli-chen. Hierfür werden wieder die Typisierten Anschlüsse herangezogen. Weitere Vergleiche werden mit dem Zusatzmodul STIRNPL von dem Programm RSTAB der Firma Dlubal und dem Programm RFEM der gleichen Firma durchgeführt. This thesis deals with head-plate-joints and their calculation possibilities. Head-plate-joints are common joining methods in steel construction for H or I profiles. These connections consist of several individual components, the bolts, the welds and the head plate itself. The usual calculation methods only apply in certain situations, namely only for loads with the internal forces normal force N, shear force Vz and bending moment My. If other loads occur, the standards do not provide any regulations for calculation. In spatial structural systems, it is often possible that all six cutting forces occur in the girders. For loads with the internal forces shear force Vy, torsional moment MT or bending moment Mz, often only the finite element method (FEM) with suitable computer software is available for calcula-tion. In this master thesis the usual calculation models from Eurocode 3 are explained. In addi-tion, the tables of the Standardised Joints in Steel Structures to DIN EN 1993-1-8 (the so-called DSTV joints of the German Steel Construction Association) and their application are explained. In this paper, a possible calculation approach for head panel joints with six cutting forces is explained. With this approach, the cutting forces are converted to one equivalent of other cutting forces to enable calculation with the valid methods from the standard. Furthermore, this calculation method is reprogrammed with the standard software Mi-crosoft Office Excel to create a practical and at the same time inexpensive calculation tool. This calculation tool should be easy to use and provide fast results. Finally, the results of this calculation method are compared with the results of other calcu-lations using the Excel calculation tool. The Standardised Joints are used again for this purpose. Further comparisons are made with the add-on module STIRNPL from the pro-gram RSTAB from Dlubal and the program RFEM from the same company. vorgelegt von: Florian Ofner Wien, FH Campus Wien, Masterarb., 2018

This paper presents an improved finite-element formulation for axially uniform electromagnetic waveguides. It allows for both dielectric and conduction losses and covers the entire range from optics down to the static limit. Propagation coefficients of small magnitude, particularly those of transmission line modes in the low-frequency regime, are computed much more accurately than with previous approaches.

Summary Burst pressure is the pressure at which vessel burst/crack and internal fluid leaks. An accurate prediction of burst pressure is necessary in chemical, medical and aviation industry. Burst pressure is a design safety limit, which should not be exceeded. If this pressure is exceeded it may lead to the mechanical breach and permanent loss of pressure containment. So burst pressure calculation is necessary for all the critical applications. To numerically calculate burst pressure material curve is essential. There are various material models which are used to define material curve, amongst them Ramberg–Osgood is very popular. Ramberg–Osgood accurately capture material curve in strain hardening region. This approach is applicable for different material grades. In this paper a finite element method is used to predict burst pressure using Ramberg–Osgood equation. These results are then compared with results obtained from elasto-plastic curve and true stress strain curve. Results obtained by finite element analysis are validated with experimental data which is considered from open literature.

The mechanical properties of porous thin films and perforated layers are affected by pore content, shape and arrangement. The experimental determination of the in-plane mechanical properties of such materials is challenging, yet reliable data are essential for materials development and component design. Analytical and numerical approaches therefore provide valuable, supplementary tools for evaluating the effect of porosity on the mechanical properties of such materials. The applicability of both the classical self-consistent method and the Mori–Tanaka approach to the estimation of the effective elastic properties of porous thin films and perforated layers is investigated in this paper. For generic model microstructures with various arrangements of pores, variable pore content and varying matrix Poisson’s ratio, the effective elastic properties predicted by the classical self-consistent method and by the Mori–Tanaka approach are quantitatively compared with results obtained by numerical experiments. Based upon this comparison, the range of validity of both the classical self-consistent method and the Mori–Tanaka approach with regard to the different arrangements of pores investigated is defined, and the deviation to be expected if critical values of pore content or inter-pore distance are exceeded and interactions between adjacent pores are occurring is assessed.

Die vorliegende Arbeit beschäftigt sich mit der strukturellen Auslegung und Optimierung von geklebten L-Stringeranbindungen innerhalb des Projekts Smart Blades. Dazu wird auf ein bereits erstelltes Finite Elemente Gesamtmodell einer formvariablen Flügelhinterkante zurückgegri en. Zur genaueren Untersuchung des mechanischen Spannungszustands werden die resultierenden Knotenverschiebungen und Antriebskräfte des Gesamtmodells in ein Submodell umgesetzt. Um in diesem Submodell die Anbindungsgeometrie zu optimieren, wird das Modell parametrisch aufgebaut. Die Parametrisierung erfolgt mithilfe der Skriptsprache APDL(Ansys Parametric Design Language) und dem Programm Ansys®Academic Teaching Advanced, Release 14.0. Dieses parametrische Submodell wird im Anschluss mit verschiedenen Randbedingungen in einer Reihe von Parameterstudien untersucht und unter Berücksichtigung von Festigkeitskriterien der Faserverbundwerksto e und der Klebung ausgelegt. Die durchgeführten Untersuchungen zeigen, dass die als Festkörpergelenk ausgeführten L-Stringeranbindungen bei der geplanten Antriebskinematik keine ausreichende Festigkeit aufweisen. Die Ergebnisse der Simulation werden im Anschluss durch verschiedene Experimente überpr üft. Dazu werden zwei Versuchskörper ausgelegt, die eine für den betrachteten Fall anwendungsnahe Geometrie aufweisen. Aus den Ergebnissen der Versuche werden im Anschluss Rückschlüsse für zukünftige Simulationen und Experimente gezogen. This paper works on the structural dimensioning and optimization of adhesively bonded single-L joint structures. It was written as part of the Project Smart Blades of the DLR. A submodelling approach was used in order to analyze the detailed stress distribution within the structure. The necessary node displacements and forces were taken out of a given Finite Element Model of the Smart Blade structure. The submodel was designed as highly parametric in order to be able to cover a large design space in the analysis. Therefore, the model was build up with the scripting language APDL(Ansys Parametric Design Language) within Ansys®Academic Teaching Advanced, Release 14.0. The parametrical submodel was later analyzed with various boundary conditions in a number of parameter studies. The influences of the model parameters on the failure criteria for the composite and adhesive materials were evaluated and an optimal solution was found for the considered design space. However, the studies show that the connections of the L-Stiffner, which are designed as flexure hinges, are not capable of withstanding the high forces under operational conditions. The results of the numerical studies were afterwards evaluated in experiments. Therefore, two test specimen were designed that represent an application-related geometry. The results of the experiments are used to give suggestions for improvements for future finite element models and experiments.

In vielen industriellen Sparten erfreuen sich Faser-Kunststoff-Verbunde (FKV) immer gr����er werdender Beliebtheit. Ihre hervorragenden gewichtsspezifischen Eigenschaften, leistungsf��higere Computerhardware sowie Simulationsprogramme bis hin zu modernen Fertigungstechnologien beschleunigen den Einsatz dieser Materialtechnologie. Um das gesamte Potential dieses Werkstoffes aussch��pfen zu k��nnen, stellt die Finite Elemente Methode (FEM) ein unverzichtbares, nummerisches Instrument dar. Das Ziel dieser Arbeit ist es, ein FEM-Modell eines U-f��rmigen Balkens aus Kohlefaser-Geflecht zu erstellen. Dieser ist so zu dimensionieren, dass das angestrebte Versagen m��glichst dominiert, sowie das Versagen an den Lasteinleitungs- und Lagerstellen unterbunden wird. An diesem Balken ist in weiterer Folge ein Experiment vorgesehen, das in einem 4-Punkt-Biegeversuch durchgef��hrt wird. Es wird ein parametrisiertes FEM-Modell erstellt, das es erm��glicht, die geometrischen Dimensionen der Geometrie des Balkens automatisiert zu ��ndern. Das FEM-Modell bildet dabei die Lagerung und Lasteinleitung des Balkens vereinfacht ab. Die Lasteinleitung findet ��ber eine Aluminium-Druckplatte statt mit der die Kr��fte fl��chig in den Balken eingeleitet werden. Dabei wird eine Kontaktformulierung angewandt. Die Lagerung erfolgt ��ber ein Aluminium-Insert im Balken. Detaillierte Untersuchungen zeigen den Einfluss der Geometrie��nderung auf das Sch��digungsverhalten. Besonderes Augenmerk wird dabei auf die Lasteinleitungsstelle und den Sch��digungsort gelegt. Die Variierung der Geometrie zielt darauf ab, die Lasteinleitungsstelle vor Sch��digung zu bewahren. Um ein Versagen mit Sicherheit ausschlie��en zu k��nnen muss diese konstruktiv umgestaltet werden. Die gewonnenen Erkenntnisse liefern eine Empfehlung f��r die Abmessungen des Balkens, der f��r das Experiment verwendet werden soll. Durch eine zuletzt durchgef��hrte Simulation, die eine Steifigkeitsreduzierung der Struktur durch Sch��digung ber��cksichtigt, soll der Schadensfortschritt dargestellt werden. Zus��tzlich wird die Lasteinleitung und Lagerung ��berpr��ft, sodass bei einer Belastung, die zum totalen Versagen der Struktur f��hren soll, keine Sch��digung auftritt., In many industrial branches, fiber-reinforced plastics (FRP) are becoming increasingly popular. Their excellent weight-specific properties, a more powerful computer hardware and simulation programs as well as modern production technologies accelerate the use of this material technology. In order to exploit the full potential of this material, the finite element method (FEM) serves as an indispensable, numeric instrument. The aim of this paper is to create an FEM-model of a U-shaped bar made of braided carbon fiber. This one has to be dimensioned, that the intended failure is as dominating as possible and that failure is suppressed at the load introduction and bearing positions. Further an experiment is carried out on this beam by a 4 point bending test. A parameterized FEM-model is created, which is able to change the geometrical dimensions of the beam automatically. The FEM-model shoes the load introduction and bearing position in a simplified manner. The load introduction takes place over an aluminium plate, which then leads the forces in a areal way into the beam. Therefore a contact formulation is applied. The bearing is made by an aluminium insert within the beam. The obtained findings provide recommendations for the dimensions of the beam, which is to be used for the experiment. A recently conducted simulation, which takes into account stiffness degradation of the structure through damage progress, should depict the damage process. In addition, the load introduction and bearing position are checked to prevent damages when being burdened, which should lead to the total failure of the structure.