The aim of this thesis is an analysis of the construction of a trailer used for transporting concrete pillars. The main part of the thesis is focused on frame construction. For the calculation of load states a multi body system was used, whereby a simulation of transport in terrain was performed. The results from these calculations will be used as limiting conditions for strength control. The method of solution is the finite element method. All acquired results will be analysed and according to them changes will be made to the frame construction. In addition to this, the thesis contains drawings documenting the above-mentioned changes.

The proposed dissertation thesis contains an analysis of conditions on the boundary between layers having varied electromagnetic properties. The research is performed using consistent theoretical derivation of analytical formulas, and the underlying problem is considered also in view of multiple boundaries including the effect of the propagation of electromagnetic waves having different instantaneous speed. The author presents a survey and formulation of the basic characteristics of methods used for electromagnetic wave propagation analysis; in this respect, special emphasis is placed on radial models. The processing of the topic involved the designing and verification (using a set of different, layered planar materials) of algorithms to analyze the electromagnetic field components. The algorithm was assembled to enable simple evaluation of all components of the electromagnetic field in relation to the speed of the wave propagation in a heterogeneous environment. The proposed algorithms are compared by means of different numerical methods for the modelling of electromagnetic waves on the boundary between materials; moreover, electromagnetic field components in common points of the model were also subject to comparison. When in conjunction with tools facilitating the analysis of material response to the source of a continuous signal, the algorithms constitute a supplementary instrument for the design of a layered material. Such design enables the realization of, for example, recoilless plane, recoilless transition between different types of environment, and filters for both optical and radio frequencies.

Im Vertrag wird die numerische Verfahrensentwicklung des Flach-Clinchklebens präsentiert. Schwerpunkte bilden hierbei die Bestimmung der Materialdaten und die anschließende Implementierung in das Simulationsmodell sowie die Modellierung des Prozesses. Es wird auf numerische Besonderheiten, wie die Kontaktabbildung zwischen den Blechen und der Klebstoffschicht sowie auf die Trennung der Klebstoffschicht und die damit verbundene Bildung von Klebstofftaschen, eingegangen. Weiterhin werden verschiedene Ansätze vorgestellt, um die Hinterschnittausbildung zwischen den Blechen zu ermöglichen und hierdurch die Handhabungsfestigkeit der Hybridverbindung zu gewährleisten. Abschließend erfolgen die experimentelle Validierung ausgewählter Verfahrensparameter sowie die Bestimmung der mechanischen Verbindungskennwerte.

Gegenstand dieser Arbeit ist die Bereitstellung eines geeigneten Simulationswerkzeuges für die numerische Untersuchung der beim Rollkontakt zwischen Rad und Schiene auftretenden Phänomene. Hierbei liegt das Hauptaugenmerk auf der kontinuumsmechanischen Formulierung des mechanischen Feldproblems kontaktierender Körper sowie dessen numerischer Lösung mittels der Finite-Element-Methode. Zur Reduzierung des bei der Simulation von Rollkontakt aus der notwendigen sehr feinen Diskretisierung der Kontaktgebiete resultierenden numerischen Aufwandes wird eine relativkinematische Beschreibung herangezogen. Diese gemischte LAGRANGE-EULER-Betrachtungsweise beruht auf der Zerlegung der Bewegung in einen Starrkörperanteil und eine dazu relative Deformation. Die Herleitung der Bewegungsgleichung für das Kontaktproblem erfordert die relativkinematische Formulierung der kontinuumsmechanischen Grundgleichungen, d.h. der Bilanzgleichungen sowie der konstitutiven Beziehungen. Eine geeignete Kontaktmechanik einschließlich der Berücksichtigung des Kontakts rauer Oberflächen und veränderlicher Kontaktrandbedingungen ist ebenfalls notwendig. Die physikalische Einbindung der Körper in die Umgebung erfolgt über NEUMANNsche und DIRICHLETsche Randbedingungen. Auf dieser Basis können die Bewegungsgleichungen der Elastomechanik hergeleitet werden, welche sich jedoch einer analytischen Lösung verschließen. Somit werden sie in ihrer schwachen Form im integralen Mittel formuliert, was der Anwendung des Prinzips der virtuellen Verschiebungen als Ausgangspunkt für die numerische Lösung entspricht. Die rechentechnische Umsetzung erfordert die inkrementelle und diskrete Formulierung der Bewegungsgleichungen unter besonderer Beachtung der Trägheits-und Kontaktterme, wobei auf die Unterscheidung zwischen Haften und Gleiten beim Tangentialkontakt besonderes Augenmerk gelegt wird. Die numerische Lösung des Finite-Element-Gleichungssystems liefert den aktuellen Beanspruchungszustand zweier Körper im Rollkontakt. Die Funktionsfähigkeit der entwickelten Algorithmen wird abschließend anhand aussagekräftiger Beispielrechnungen zum statischen Kontakt und zum stationären Rollkontakt demonstriert, deren Ergebnisse gute Übereinstimmung mit analytischen Vergleichslösungen, soweit verfügbar, aufweisen. / Scope of this work is the preparation of a suitable simulation tool for the numerical investigation of rolling contact phenomena. The main focus lies on the continuum–mechanical formulation of the mechanical field problem of contacting bodies and its numerical solution within the framework of the Finite Element Method. For reducing the numerical effort in rolling contact simulation, induced by the necessity of a very fine discretization within the expected contact area, a relative–kinematical description is utilized. This arbitrary LAGRANGian–EULERian approach is based upon the decomposition of the total motion into a rigid body motion and a superimposed deformation. The derivation of the equation of motion for the contact problem requires the relative–kinematical formulation of the continuum–mechanical fundamental equations, i. e. the balance equations and the constitutive relations. A suitable contact model including the contact of rough surfaces and varying contact boundary conditions is also necessary. The physical embedding into the environment is accomplished by NEUMANN and DIRICHLET boundary conditions. Based upon that foundation the elastomechanics’ equations of motion are derived, which however can not be solved analytically in general. Hence, the equations of motion are transferred into their weak form by the application of the principle of virtual displacements serving for the numerical solution. The implementation of the problem demands for an incremental and discrete formulation of the equations, especially regarding the terms of inertia and the contact terms. Thereby, special attention has to be paid to the distinction between sticking and sliding within the framework of the tangential contact analysis. The numerical solution of the finite elements’ system of equations provides the state of stress, displacement and contact of two bodies in rolling contact. The reliability of the developed algorithms is finally verified by means of meaningful numerical examples for both static contact and for stationary rolling contact, whereby the numerical results coincide well with available analytical reference solutions.

Above ground steel storage tanks are used worldwide for the storage of various liquids. EN 14015:2005, which has traditionally been used to design the tanks, does not necessarily fulfil the requirements of the Swedish Building Code. This has been underlined by hand calculation models in EN 1993-1-6:2007, EN 1993-4-2:2007 and numerical analysis using Finite Element Method (FEM). Therefore, this thesis investigates the differences between these design models and, preliminarily, the use of high-strength steel in tank shells. A 10600 m3 cylindrical steel tank of diameter 26 m and height of 21 m located in Gothenburg, Sweden is studied. The study is limited to the assessment of the stress in the shell courses due to the hydrostatic pressure from the fluid action of a filled tank, and the buckling behaviour of the shell courses of an empty tank subjected to self-weight, snow and wind loads. Particularly, models of the tank shell with a yield strength of 355 MPa are investigated in detail, while the results of the 700 MPa model are considered as preliminary study, since the material is currently not used for tank shells. An analysis of the fluid action on the tank shell courses in each of the three hand calculation models, showed that the EN 14015 model utilizes thicker courses than both Eurocodes. One benefit of the Eurocode models is that they do not limit the thickness of the shell courses, but it is still necessary to have thicker courses in the upper part of the tank in order to achieve sufficient resistance against buckling. EN 14015:2005, on the other hand, limits the minimum thickness to 6 mm for the investigated tank. Furthermore, only EN 1993-1-6 is applicable to the models with a yield strength of 700 MPa as per EN 1993-1-12 and this resulted in a uniform shell thickness of 6 mm. However, an increase in yield strength has no buckling benefits whatsoever.  Buckling is the most critical aspect as observed in this study. EN 14015 has no specific buckling calculations but uses the approach of determining the number of stiffening rings which are deemed adequate against buckling. In this study, 3 secondary stiffening rings were found to be adequate. In comparison, the results of EN 1993-4-2 are very conservative and lead to a very high and uneconomical number of stiffening rings, ranging from 30 to 52 stiffening rings depending on the reliability class. EN 1993-1-6 resulted in 6-17 stiffening rings, for reliability classes 1-3 and fabrication classes A-C. Therefore, the so-called analytical models in the Eurocodes result in a much denser spacing of stiffening rings than 14015:2005.  The buckling stresses due to the design loads were found to be lower than the yield strength of the tank shells for both hand calculation and FEM models. This means that the tank shells failed in buckling before the yield strength of the material was reached. Based on the parametric study of the EN 1993-1-6 (355 MPa) model regarding reliability class 1 and fabrication class A using FEM, the spacing of the stiffening rings can be increased up to 60 % (from 3825 mm to 6120 mm) with the variable loads also increased simultaneously up to 3.8 times before the shell buckles. Therefore, the design of future tanks using numerical analysis guarantee’s more reliability than all the aforementioned standards.  The design for buckling according to EN 14015 is only valid for a design snow load and under-pressure ≤ 1.2 KN/m2. However, according to the standard itis possible to agree to use it for larger actions or use another design model for buckling.

This document is focused on the elucidation of embankment deformation nearby žst. Valašská Polanka, with subsequent proposal of remediation measures, for which the own software and commercial software Plaxis 2D were used.

TBI stands for Traumatic Brain Injury and refers to damage to the brain resulting from an external physical force, such as a blow, jolt, or penetrating injury to the head. Common causes of TBI include falls, motor vehicle accidents, sports injuries, and violence and has been linked to thousands of deaths and injuries in the US and the EU alike. This thesis was aimed to localise certain TBI to a specific part of the brain by exerting similar loading conditions on an Finite Element Method (FEM) of the rat brain as physical experiments conducted on living rats. By comparing the strain in 7 vital parts of the brain to injury diagnosis conducted in the physical experiments, an effort was made to link localised strain to injury diagnosis. The results indicate that strain in the thalamus and hypothalamus are linked with a loss of consciousness while strain in the hypothalamus coupled with the neocortex correlates greatly with activity-based behaviour changes. Lastly, injury associated with emotional changes are believed to stem from large strains in the neocortex. There is a theory suggesting that the structure of myeline, which provides support in motion and movement patterns of biological systems in humans and animals (known as biomechanical kinematics), could have an impact. However, more studies are needed to confirm and determine the exact cause. / TBI, från engelskans Traumatic Brain Injury, står för Traumatisk Hjärn Skada och syftar på en skada i hjärnan till följd av enyttre fysisk kraft, såsom ett slag, stöt eller genomträngande skada i huvudet. Vanliga orsaker till TBI inkluderar fall, motorfordonsolyckor, sportskador och våld och har kopplats till tusentals dödsfall och skadade i både USA och EU. Denna rapport syftar till att försöka lokalisera viss TBI till en specifik del av hjärnan genom att utöva liknandebelastningsförhållanden på en finit elementmetod (FEM) modell av råtthjärnan som fysiska experimentutförs på levande råttor. Genom att jämföra belastningen i 7 vitala delar av hjärnan med skadediagnos som utfördes i de fysiska experimenten gjordes en ansträngning för att koppla lokaliserad belastning till skadediagnos. Resultaten indikerar att skada i thalamus och hypotalamus är kopplade till en förlust av medvetande medan belastning i hypotalamus i kombination med neocortex korrelerar kraftigtmed aktivitetsbaserade beteendeförändringar. Slutligen är skador i samband med känslomässiga förändringartros härröra från skada i neocortex. Det finns teori som tyder på attstruktur av myelin, som ger stöd i rörelse och rörelsemönster av biologiskasystem hos människor och djur (känd som biomekanisk kinematik), kan ha en inverkan.Det behövs dock fler studier för att bekräfta och fastställa den exakta orsaken.

Für die Trassierung von Straßenverkehrsanlagen hat sich neben anderen Methoden die Verwendung von Biegelinealen als vorteilhaft erwiesen und vor über 50 Jahren etabliert. Inzwischen hat der Einsatz moderner Entwurfssoftware in den Straßenbauverwaltungen und Planungsbüros das Biegelineal trotz seiner Vorteile aus der Praxis verdrängt. Keines der Entwurfsprogramme legt das strukturmechanische Prinzip des Biegelineals zugrunde, da die Verformungen des zu Trassierungszwecken ausgelegten Biegelineals nicht exakt berechnet werden können. An diesem Punkt setzt die vorliegende Arbeit an, sie umgeht das Problem auf numerischem Wege unter Anwendung der Finiten Elemente Methode (FEM). So lassen sich über Strukturanalysen die Verformungen einer um seine Hauptträgheitsachsen punktuell ausgelenkten, prismatischen Balkenstruktur mit doppeltsymmetrischem Querschnitt berechnen. Mit der Analyseantwort ergeben sich insbesondere die dreidimensionalen Koordinaten einer Punktfolge, welche die Biegelinie quasiexakt repräsentiert. Die dreidimensionale Biegelinie setzt sich aus einer Achse und einer Gradiente zusammen und ist im Rahmen der Vorplanung geeignet, eine richtliniengerechte Straßenverkehrsanlage zu erzeugen. Das Untersuchungsergebnis stellt eine neuartige Grundlage für ein dreidimensionales Trassierungsverfahren dar, bei dem ein mathematisch modelliertes Biegelineal im Digitalen Geländemodell (DGM) verformt wird.

Cette thèse porte sur l'estimation simultanée du coefficient de diffusion et du terme source régissant le modèle de transport de la température dans les plasmas chauds. Ce phénomène physique est décrit par une équation différentielle partielle (EDP) linéaire, parabolique du second-ordre et non-homogène, où le coefficient de diffusion est distribué et le coefficient de réaction est constant. Ce travail peut se présenter en deux parties. Dans la première, le problème d'estimation est traité en dimension finie ("Early lumping approach"). Dans la deuxième partie, le problème d'estimation est traité dans le cadre initial de la dimension infinie ("Late lumping approach"). Pour l'estimation en dimension finie, une fois le modèle établi, la formulation de Galerkin et la méthode d'approximation par projection sont choisies pour convertir l'EDP de transport en un système d'état linéaire, temps-variant et à entrées inconnues. Sur le modèle réduit, deux techniques dédiées à l'estimation des entrées inconnues sont choisies pour résoudre le problème. En dimension infinie, l'estimation en-ligne adaptative est adoptée pour apporter des éléments de réponse aux contraintes et limitations dues à la réduction du modèle. Des résultats de simulations sur des données réelles et simulées sont présentées dans ce mémoire. / This work deals with the diffusion and source term estimation in a heat transport model for tokamaks plasma . This phenomenon is described by a second-order linear parabolic partial differential equation (PDE) with distributed diffusion parameter and input. Both "Early lumping" and "Late lumping" approaches are considered in this thesis. First, once the heat model is chosen, the Galerkin formulation and the parameter projection method are combined to convert the PDE to a set of ordinary differential equations (ODEs). Then, two estimation methods able to give optimal estimates of the inputs are applied on the reduced model to identify simultaneously the source term and the diffusion coefficient. In the infinite dimensional method, the adaptive estimation technique is chosen in order to reconstruct "freely" the unknown parameters without the constraints due to the model reduction method. Simulation results on both simulated and real data are provided to attest the performance of the proposed methodologies.

The increased use of continuously welded rails in the railway systems makes it necessary to increase the control of the rail stresses to avoid instability and damages of the rails. Large stresses are especially prone to appear at discontinuities in the railway systems, such as bridges, due to the interaction between the track and the bridge. The interaction leads to increased horizontal forces in the rails due to the changed stiffness between the embankment and the bridge, temperature variations, bending of the bridge structure because of vertical traffic loads and braking and traction forces. If the compressive rail stresses become too high it is necessary to use costly and maintenance-requiring devices such as rail expansion joints and other rail expansion devices. These devices increase the railway systems life cycle cost and should if possible be avoided. The use of non-ballasted track on high-speed railways, tramways and subways, has increased since this kind of track requires less maintenance and according to some investigations have a lower life cycle cost compared to ballasted track. The non-ballasted track is usually made of a track slab to which the rails are connected through fastenings. The track slab is connected to the bridge structure and held in place by shear keys. When non-ballasted tracks are used in populated areas it is sometimes necessary to introduce some vibration and noise damping solution. One of the possible solutions is to introduce a floating slab mat (elastic mat) under the track slab on the bridge. The influence of the floating slab mats properties on the rail stresses is investigated in this degree project. The investigation was performed through a numerical modelling of two railway bridges using the finite element software SOFiSTiK. The results from the investigation showed that there was a small reduction of the compressive rail stresses by approximately 3 – 7% (depending on the stiffness of the elastic support, load positions and the properties of the mat) when a mat was installed under the track slab. The results from the investigation also showed that there was a small reduction (up to approximately 1 %) of the compressive stresses in the rail when the thickness of the mat was increased, and the stiffness of the mat was reduced. This reduction of the compressive stresses is assumed to be caused by the mat being mounted on the sides of the shear keys. The lower stiffness of the mat allows the track slab and the bridge deck to move more freely parallel to each other in the horizontal direction. This leads to a decrease of the stresses in the rail due to a lower interaction between the track and the bridge. It was also shown that the rail stresses increased if the friction between the slab mat and the bridge deck was considered. This is because of an increase of the interaction between the track and the bridge due to the mats horizontal stiffness. / Den ökade användningen av kontinuerligt svetsade räler i järnvägsnäten i världen leder till en ökad kontroll av rälsspänningarna för att undvika instabilitet och skador på rälsen. Särskilt vid en diskontinuit i järnvägssystemet, som vid broar, kan stora tillskottspänningar i rälsen uppstå till följd av interaktionen mellan spår och bro. Interaktion leder till ökade horisontella krafter som verkar på rälsen och beror på den förändrade styvheten mellan järnvägsbank och bro, temperaturvariationer, nedböjning av bron på grund av vertikala trafiklaster samt broms- och accelerationskrafter. Om spänningarna i rälsen blir för stora behöver kostsamma och underhållskrävande dilatationsfogar införas. Dessa dilatationsfogar ökar järnvägssystemets livscykelkostnad och är något som ska undvikas att införas i den mån det är möjligt. Användningen av ballastfritt spår för höghastighetsjärnvägar, spårvägar och tunnelbanor ökar på grund av att dessa spår kräver mindre underhåll och har enligt vissa undersökningar en lägre livscykelkostnad i jämförelse med ballasterat spår. Ballastfritt spår består oftast av en betongplatta till vilken rälsen är kopplad genom befästningar. Plattan är i sin tur kopplad till underbyggnaden genom skjuvförbindare som håller plattan på plats. När ballastfritt spår används i bebodda områden är det ibland nödvändigt att ta till vibrations- och ljuddämpande åtgärder. En åtgärd som används på brokonstruktioner för att minska vibrationer och ljudföroreningar är att montera en vibrationsdämpande matta, som är tillverkad av ett elastiskt material, mellan betongplattan och broöverbyggnaden. I detta examensarbetet undersöks hur den vibrationsdämpande mattans egenskaper påverkar rälsspänningarna. Resultaten från undersökningen visar att spänningarna i rälsen minskar med cirka 3–7 % (beroende på det elastiska stödets styvhet, lastpositioner och mattans egenskaper) när en elastisk matta installeras under spårplattan i jämförelse med när ingen matta används. När mattans tjocklek ökar och när styvheten sänks minskar spänningarna med cirka 1 % i jämförelse mellan den tjockaste och tunnaste mattan. Denna minskning av spänningarna antas bero på att den vibrationsdämpande mattan som är monterad på sidan av skjuvförbindarna ger en möjlighet för spåret och bron att förskjutas fritt parallellt varandra innan en interaktion mellan spår och bro uppstår. Det visade sig även att om friktionen mellan mattan och broöverbyggnaden medräknas ökar spänningarna i rälsen. Detta beror på att mattan då skapar en större interaktion mellan spåret och bron gentemot fallet då mattans horisontella styvhet inte beaktas.