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Examensarbetet har skett inom mastersprogrammet Maskinkonstruktion på KTH. Arbetet gjorde tillsammans med Epiroc genom Svea Teknik AB. I dagens gruvarbete använder nästan alla borr- och sprängteknik, men det finns stora problem med detta. Epiroc har börjat utveckla så kallade Mobile Miners, som är konstruerade för att bryta malm utan borr- och sprängteknik. Maskinen ska ha möjlighet att göra alla processer i samma maskin istället för borr- och sprängtekniken, där maskiner byts beroende på process. Den nya tekniken använder sig av ett skärhjul för att utvinna malm. En av maskinerna Epiroc har konstruerat är Mobile Miner 40 V. Maskinen har två moduler, drivmodulen, där alla typ av drivning som hydraulpumpar är placerade och avverkningsmodulen, där skärhjulet sitter. Från tidigare versioner av Mobile Miner har det upptäckts, att det blir väldigt stora vibrationer i operatörshytten, som sitter på drivmodulen. För den nya 40 V skall kopplingen mellan modulerna kunna kopplas isär vid avverking. Dagens koncept är likt en dragkrok, som tillåter rotation i tre frihetsgrader, vilket är något som nu anses vara en risk på grund av sämre stabilitet. De tre olika leden är gir-, roll-, och tipp-led och det är roll-led som inte är önskat då 40 V är väldigt hög relativt sin bredd, vilket ger en ökad risk för tippning. Syftet med detta examensarbete var att utveckla nya stabilare koncept. Utifrån detta gjordes en parameteranalys för att definiera vad en stabilare koppling är. Nya koncept generades och dessa evaluerades med hjälp av en Pughs matris. Två koncept valdes att vidareutvecklas utifrån de givna kraven. Koncept A har låsning i tipp-led med hjälp av en krokkonstruktion, där rotationsaxlarna är separerade samtidigt som koncept B har låsningen i gir-led med hjälp av två hydrauliska cylindrar där rotationsaxlarna skär varandra likt en kardanknut. Med två frihetsgrader utsätts kopplingen för högre laster. Dimensioneringen skedde utifrån det värsta lastfallet, vilket är när avverkningsmodul kör över ett gupp och tvingar med drivmodulen. De två nya koncepten blev stabilare enligt parameteranalysen, men är något större än dagens koncept. / This Master Thesis has been done within the Master's program in Machine Design at KTH. The work was carried out together with Epiroc through Svea Teknik AB.  Today almost all mining uses drill and blast techniques, but there are major problems with this. Epiroc has started to design a so-called Mobile Miners, which are designed to excavate ore without drill and blast technology. The machine should be able to do all processes in the same operation instead of the drill and blast technology where different machines are used depending on the process. The new process uses only a cutting wheel to excavate ore. One of the machines Epiroc has designed is the Mobile Miner 40 V. The machine has two modules, the power module where all types of power supply, such as hydraulic, pumps are located and then the mining module where the cutting wheel is located. From other Mobile Miner it has been discovered that there will be very large amount of vibrations in the operator cabin, which is located on the power module, so for the new 40 V the idea is that the coupling between the modules can be disconnected while operating. The current concept is similar to a towbar that allows rotation in three degrees of freedom, which is something that was later considered a risk. The three different axes are yaw, roll, and pitch axis and it is roll axis which is not desired since 40 V is very high relative to its width, which gives a risk of tipping. The purpose of this Master Thesis were to develop a more stable concept. Based on this, a parameter analysis was made to define what a more stable coupling is. New concepts were generated and then evaluated using a Pugh's matrix. Two concepts were chosen to be further developed based on the given requirements.  Concept A has the locking procedure in pitch axis with the aid of a hook construction where the rotation axes are separated meanwhile in concept B has the locking procedure in the yaw axis with the help of two hydraulic cylinders where the rotation axes intersect each other like a universal joint. With two degrees of freedom, higher forces are transmitted. The dimensioning was based on the worst load case, which is when the mining module runs over a bump and carry the power module. The two new concepts became more stable according to the parameter analysis, but are somewhat bigger than the current concept.

This thesis investigates the historic and architectural significance of the Buchanan House in Bells Bend, Nashville, Tennessee, in hopes that it will be protected and conserved. Artifacts from the University of Tennessee surveys conducted by David Anderson and Derek Anderson in 2009 and 2010 were used to establish whether or not there were any intact American Civil War period deposits. Spatial analysis was used to identify locations of activity areas. Historic documents were used to establish the occupants of the Buchanan House. This thesis concluded that while there were no definitive Civil War period deposits, the Buchanan House still provides an ideal spot for a museum commemorating the Battle of Bells Bend, owing to its close proximity to the battle, and because it offers a unique perspective on the civilian experience during the Civil War, one that demonstrates a long history of resistance and resilience.

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No / Iron Age studies in northern Britain have been dominated by one monument form, the broch. This focus on these monumental towers of the Atlantic Scotland, perhaps at the expense of other archaeological evidence, has brought about a strong division in the archaeological community. MacKie and Armit have both recently summarized the development of broch studies detailing the opposing arguments for the date of construction. In recent years archaeological evidence for these monuments has indicated an indigenous development rather than being associated with the movement of Iron Age peoples. This paper presents new chronological data for the construction of a Shetland broch and examines the archaeological repercussions for the 'early' chronology provided by these dates. Excavations at Old Scatness in the South Mainland of Shetland have revealed new evidence for a broch and defended Iron Age Village.

No / Following Wheeler's excavations at Maiden Castle, the multivallate hillforts of Wessex came to be seen as responses to a specific form of warfare based around the massed use of slings. As part of the wider post-processual 'rethink' of the British Iron Age during the late 1980s and 1990s, this traditional 'military' interpretation of hillforts was increasingly subject to criticism. Apparent weaknesses in hillfort design were identified and many of the most distinctive features of these sites (depth of enclosure, complexity of entrance arrangements, etc) were reinterpreted as symbols of social isolation. Yet this 'pacification' of hillforts is in many ways as unsatisfactory as the traditional vision. Both camps have tended to view warfare as a detached, functional, and disembedded activity which can be analysed in terms of essentially timeless concepts of military efficiency. Consideration of the use of analogous structures in the ethnographic record suggests that, far from being mutually exclusive, the military and symbolic dimensions are both essential to a more nuanced understanding of the wider social role of hillforts in Britain and beyond.

Le comportement à long terme des excavations souterraines est un enjeu social et économique majeur, en particulier dans le contexte du stockage en formation géologique profonde de déchets nucléaires à Haute Activité et Vie Longue (HAVL). Plusieurs galeries expérimentales ont été creusées dans le laboratoire de recherche souterrain de Meuse/Haute-Marne situé près de Bure en France, où des études sont menées pour comprendre le comportement global de la roche constitutive : l’argilite du Callovo-Oxfordien (COx).L’objectif de cette thèse est d’effectuer une modélisation avec Code_Aster d’ouvrages souterrains, et en particulier d’une des galeries du laboratoire de Meuse/Haute-Marne, en prenant en compte une approche non locale, l’effet du fluage et le couplage hydromécanique dans le cadre de la mécanique des milieux poreux, et de comparer les résultats numériques avec les données expérimentales disponibles.Le modèle élastoviscoplastique spécifiquement utilisé pour cette étude est le modèle L&K : il offre d’une part un couplage entre le comportement instantané et différé, et prend en compte d’autre part la dilatance, paramètre qui gouverne les déformations volumiques du matériau lors d’une sollicitation, et ses fortes variations, caractéristique essentielle des géomatériaux et en particulier du COx. La présence d’un fluide s’écoulant à travers le matériau va ajouter une composante hydraulique à la modélisation, dont le couplage avec la mécanique est assuré par les équations de Biot. Une autre nouveauté de ce travail concerne le couplage entre ce comportement rhéologique complexe et une approche non locale dans un cadre industriel. Parmi les méthodes de régularisation disponibles dans Code_Aster, la méthode second gradient de dilatation a été choisie parce que bien adaptée aux géomatériaux. Son but est de corriger la dépendance au maillage et les solutions numériques localisées.Une fois les outils numériques opérationnels et les paramètres du modèle L&K calés sur des essais effectués en laboratoire sur des échantillons, un bon accord général a été trouvé entre les résultats numériques et les mesures in situ, sans aucun recalage des paramètres. Les effets du temps observés expérimentalement sur l’évolution des déplacements et des pressions d’eau sont retrouvés au sein d’une même modélisation, validant ainsi la démarche prédictive suivie / The long term behaviour of underground excavations is a social and economic stake, in particular in the context of storage in deep geological formation of high activity and long life nuclear waste. Several experimental galleries have been dug in the underground research laboratory (URL) of Meuse/Haute-Marne located close to Bure in France, where studies are leaded in order to understand the global behaviour of the constitutive rock which is the Callovo-Oxfordian (COx) argillite.The purpose of this PhD Thesis is to establish a modelling with Code_Aster of underground excavations, and especially of a Meuse/Haute-Marne laboratory gallery, taking into account non local approach, creep effect and hydromechanical coupling in the framework of the mechanics of porous media, and then to compare numerical results with available experimental data.The specific elastoviscoplastic model used in this study is the L&K model: it offers a coupling between instantaneous and delayed behaviour, and it takes into account the dilation, parameter which governs the volume strains of the material during a solicitation, and its strong variation, a specificity of geomaterials and so of COx argillite. The fluid flowing through the material adds a hydraulic component to the modelling, which is coupled to mechanic component thanks to Biot’s equations.Another novelty of this work concerns the coupling between such complex rheological behaviour and a non local approach in an industrial way. Among methods of regularization available in Code_Aster, the second gradient of dilation is well fitted to geomaterials. Its aim is to correct mesh dependency and numerical localized solutions.After describing numeric tools and setting parameters of the L&K model on laboratory tests, a good general agreement was found between numeric results and in situ measures, without resetting parameters. Time effects experimentally measured on displacement and pore pressure evolution are observed in the same modelling, validating the followed predictive approach

Dans le cadre de la gestion des déchets radioactifs dits de moyenne activité à vie longue et de haute activité, la France a fait le choix du stockage géologique profond dans une formation rocheuse située à l’est du bassin parisien, dans une zone tectoniquement stable. Cette formation d’argilites du Callovo-Oxfordien a été choisie pour ses propriétés de rétention des radionucléides puisqu’elle est très peu perméable. Un laboratoire de recherche souterrain a été construit à environ 500 mètres de profondeur afin d’étudier in-situ les propriétés de la roche. Il a été montré que l’argilite du Callovo-Oxfordien présente une anisotropie liée à sa formation géologique. L’objectif principal de cette thèse est de pouvoir reproduire le comportement mécanique anisotrope à l’aide d’un modèle de comportement élasto-plastique. Le modèle de comportement thermo-élasto-viscoplastique et isotrope nommé LKR est la résultante de tout le savoir-faire et l’expertise d’EDF en ce qui concerne le dimensionnement d’ouvrages souterrains. On cherche donc à appliquer une méthode de prise en compte de l’anisotropie structurelle caractérisant plusieurs types de géomatériaux dont l’argilite du Callovo-Oxfordien à ce modèle de comportement. Afin d’atteindre cet objectif, deux méthodes de prise en compte de l’anisotropie développées dans la littérature scientifique sont appliquées à un modèle de Drucker-Prager à écrouissage linéaire négatif et sont comparées. La première méthode consiste à introduire un tenseur de microstructure ou de fabrique permettant de définir les orientations préférentielles du matériau. La seconde méthode est l’approche par plan de faiblesse qui consiste à décrire le comportement anisotrope du matériau via deux mécanismes distincts, l’un décrivant le comportement de la matrice rocheuse isotrope et l’autre décrivant les plans de faiblesse. C’est par ce deuxième mécanisme que l’anisotropie est introduite. Ces deux applications ont été faites dans le logiciel libre de simulation en mécanique, Code Aster, développé par EDF et ont permis d’appréhender les difficultés numériques de chacune de ces méthodes, et de choisir l’approche la plus pertinente pour l’extension du modèle LKR. Ainsi, c’est la méthode avec le tenseur de fabrique qui est, dans notre cas, la plus adaptée. Elle a donc été appliquée au modèle LKR. Cette nouvelle extension au modèle permet de prendre en compte la dépendance à l’orientation du matériau des résistances en compression. Dans ces travaux, on se place dans le cadre de la mécanique des milieux continus. L’anisotropie est introduite seulement dans le mécanisme élasto-plastique du modèle de comportement LKR. / Within the framework of radioactive waste management, for long-lived and high-level radioactive waste, France has chosen deep geological storage. This storage will be located in a rock formation, in the east of the basin Parisian, in a tectonically stable area. This Callovo-Oxfordian claystone formation was chosen for its radionuclides retention properties since it is not very permeable. An underground research laboratory was built 500 meters deep to study the properties of the rock in-situ. The Callovo-Oxfordian claystone has been shown to exhibit anisotropy related to its geological formation. The main objective of this PhD thesis is to reproduce anisotropic mechanical behaviour using an elasto-plastic constitutive model. The thermo-elasto-viscoplastic and isotropic behaviour model named LKR is the result of all EDF’s knowledge and expertise in the design of underground structures. Therefore, we seek to apply a method of taking into account structural or inherent anisotropy characterizing several types of geomaterials including Callovo-Oxfordian claystone to this LKR constitutive model. In order to achieve this objective, two methods of taking anisotropy into account and developed in the scientific literature are applied to a Drucker-Prager model with linear softening and then are compared to each other. The first method consists of introducing a microstructure or fabric tensor to define the preferential orientations of the material. The second method is the weakness plane approach which consists of describing the anisotropic behaviour of the material through two distinct mechanisms, one describing the behaviour of the isotropic rock matrix and the other describing the weakness planes. It is through this second mechanism that anisotropy is introduced. These two applications were made using the free mechanical simulation software, Code Aster, developed by EDF. This allowed to understand the numerical difficulties of each of these methods, and to choose the most relevant approach for the extension of the LKR model. Thus, it is the method with the fabric tensor which is, in our case, the most suitable. It was therefore applied to the LKR model. This new extension to the model enables the material orientation dependency of the compression strengths to be taken into account. In this work, the mechanics of continuous media are considered. Anisotropy is introduced only into the elasto-plastic mechanism of the LKR behaviour model.

The essay deals with the early archaeology in Sweden during the 17th and 18th centuries in generally and with Henric Jacob Sivers excavations at Skrickerum in particularly. In the medieval, Christian Sweden, the relics from the antiquity was considered merely as symbols of the heathen past  but with the foundation of Sweden as a united kingdom they awoke interest as symbols for the nation and were used as tools in the nation building. The interpretation of the antiquity and the ancient relics where done with the Bible and the ancient writers of Greece and Rome as guides and sources. With the new scientific approach, inspired by the Enlightenment, the Swedish antiquity and its relics gained other meanings and understandings and during the early 19th century Swedish archaeology developed into a scientific subject. The aim of this essay is to retain a deeper understanding for how Swedish antiquity was looked upon during the period between the Renaissance and 1800 among scholars of the time. What similarities and differences can be spotted in a comparison with archaeology of today? Due to this, the essay concentrate on a few, selected scholars from each century and takes a look at questions like; what was considered antiquities, how where they interpreted and what part did the Christianity, and later on the Enlightenment, play in the view upon Sweden´s ancient past. In order to find answers on a broader and deeper level, the essay makes a detailed study of excavations performed by Henric Jacob Sivers at Skrickerum, Östergötland in 1757. Sivers, who was a priest and a scholar born and educated in Germany, was inspired by the new scientific view and very interested in the ancient past, he collected antiques and called himself “fornälskare”, antique lover. The excavations at Skrickerum took place during two days in June 1757 and Sivers documented the work rather thoroughly in his publication Berättelse om några nyligen i Tryserums Sokn, Tiust Härad och Calmare Län, öpnade hedniska Grafhögar och the theruti fundna Saker (Sivers 1758). How were these excavations conducted and how did they differ from excavations of today, in theoretical, methodical and conductional aspects? Sivers’ publication will give the answers and help us get a glimpse of Swedish archaeology in its early state.