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Jämtlands berggrund består till stora delar av sedimentära bergarter som har genomgått olika grader av metamorfos under den kaledoniska orogenesen. I Östersunds centrala delar påträffas nästan enbart svartskiffer med låg metamorfosgrad. På flera platser i Östersund har det uppkommit skador på byggnader till följd av svällning i skiffern. Svällning uppstår när berggrunden exponeras för luft och vatten. Pyrit och kalcit som finns i skiffern reagerar och bildar gips, vilket orsakar volymökning. Under arbetet genomfördes laborativt svällförsök, där en del av proverna hölls torrt medan en del fuktades. Proverna undersöktes vidare med röntgendiffraktion för att kvantifiera mineralhalter. Svällförsöket genomfördes i syfte att utveckla en metod för bedömning av svällrisk i projekteringsskede för nya anläggningar i berg. För att förhindra skador till följd av svällning har flertal åtgärder testats, där försöken har inneburit att stänga ute syre från berggrunden genom att hålla berggrunden under grundvattennivån eller på olika sätt försegla exponerade bergytor. Det finns flertal faktorer som påverkar svällbenägenhet, i arbetet diskuteras bland annat påverkan av svavelhalt, pH och temperatur. Slutligen observerades <0,1wt% gips i samtliga prover från undersökningsområdet genom XRD analys, samtliga prover hade även en låg halt av pyrit och magnetkis. De låga halterna och standardavvikelse för analysmetoden medförde att skillnad i mineralogi före och efter utfört svällförsök ej kunde påvisas. Det är fortsatt viktigt att ha i åtanke att berggrunden i området har rätt förutsättningar för svällning även om resultaten inte visar någon skillnad i gipshalt före och efter utfört svällförsök. / Jämtlands bedrock mainly consists of sedimentary rocks that has been metamorphosed during the Caledonian orogenesis. In the central parts of Östersund almost only black shale with a low grade of metamorphism is encountered. Damages on buildings has occurred due to swelling in shale in several places in Östersund. Swelling occurs when the bedrock is exposed to water and air. Pyrite and Calcite in the shale reacts and forms gypsum, which causes volume expansion. During this study laboratory swelling tests were performed, where one part of the samples was kept dry while the other part was exposed to water. The samples were examined with x-ray diffraction to quantify the mineral content. The swelling tests were performed with the purpose of evaluating XRD as a method for predicting the swelling risk in the early stage of planning for new facilities in the bedrock.To prevent damages caused by swelling several methods have been tested, where the attempts included shutting out oxygen from the bedrock by keeping it below the ground water level and by sealing the rock surface in different ways. There are multiple factors that affects the swelling risk, this work discusses influence from sulfur content, pH and temperature. Lastly <0,1wt% gypsum was observed in all samples from the survey area through XRD analysis, a low amount of pyrite and pyrrhotite was also seen in all samples. The low amounts in combination with standard deviation in the analysis made it difficult to prove any difference in mineralogy due to the swelling tests. Hence it is still important to keep in mind that the bedrock in the area has the right conditions for swelling even though the results show no difference in the amount of gypsum between the dry and wet samples.

Triple oxygen and hydrogen isotope analysis of the structurally-bound water in gypsum can provide a direct measure of past hydrologic variability. This thesis presents the development of the water extraction and isotopic measurement procedures, the calculation of the gypsum-water isotope fractionation factors, and the application of the method to constrain the palaeohydrologic conditions in two temporally and geographically disparate sites. Measurement of the isotopic composition of gypsum hydration water is used to examine the hydrological changes that occurred during the Terminal Classic Drought of the Maya lowlands (~800-1000 CE), coincident with the period when the Classic Maya Civilization of Mesoamerica collapsed. The data provide a complete and direct archive of hydrological conditions that have previously been limited to ice core records. Mean annual rainfall is shown to have decreased by between 41% and 54%, with intervals of up to 70%, compared to present-day conditions. This study has also shown for the first time that relative humidity was 2%-7% lower during the Terminal Classic Drought compared to today. The methodology is also applied to the massive gypsum deposits in the marginal and deep basins of the Mediterranean to interpret the chemical evolution of parent water bodies during the Messinian Salinity Crisis (5.97-5.3 Ma). By combining the measurement of gypsum hydration water with other traditional (e.g. strontium) and novel (e.g. calcium and barium) isotope tracers, the hydrological changes during the deposition of Primary Lower Gypsum units of the Sorbas Basin in southeastern Spain, the Upper Gypsum units of Sicily, and deep basin deposits have been constrained. The results indicate that all deposits experienced a significant freshwater contribution to the mother fluids from which they formed. It is proposed that obliquity-controlled sea level and eccentricity-modulated precession, superimposed on longer-term tectonic restriction of the Mediterranean-Atlantic exchange, together controlled the varying depositional environments during the formation of the Messinian Salt Giant. This thesis demonstrates that the analysis of gypsum hydration water is a powerful tool for palaeoclimate reconstruction. The methodology can be applied to gypsum (and other hydrated minerals) in a wide range of settings across geological space and time, providing a rich source of information about the environmental conditions under which they formed.

Fly ash is a waste product from thermal power plants where pulverised coal is used for the generation of electricity. Fly ash is being utilised in the blended cements, additive for concrete and manufacturing of concrete blocks and bricks. Fly ash-lime-gypsum bricks are being manufactured and marketed throughout the country. The literature review on fly ash-lime-gypsum (FALG) mixtures as intended to manufacture bricks or blocks for masonry applications indicates several gaps in understanding the various aspects of the technology. The present thesis is an attempt to understand the behaviour of compacted stabilised fly ash mixtures for the manufacture of fly ash bricks and characteristics of masonry using such bricks. A brief introduction to the technology of compacted stabilised fly ash bricks for structural masonry is provided. Review of the literature on fly ash-lime and fly ash-lime-gypsum mixtures, and fly ash bricks is provided in chapter 1. Chapter 2 gives details of the experimental programme, properties of raw materials used in the experimental investigations, methods of preparing different types of specimens and their testing procedures. Chapter 3 deals with the strength and absorption characteristics of compacted stabilised fly ash mixtures in greater detail. The main focus of the investigations is on arriving at the optimum stabilizer-fly ash mixtures considering density, stabilizer-fly ash ratio, curing conditions, etc. as the variables. Therefore the parameters/variables considered in the investigation include: (a) density of the compacted fly ash mixture, (b) stabilizer-fly ash ratio, (c) curing duration (normal curing and steam curing) and (d) dosage of additives like gypsum. Some of the major conclusions of the investigations are (a) compressive strength of compacted stabilised fly ash mixtures is sensitive to dry density of the specimens and the strength increases with increase in density irrespective of stabiliser content and type of curing, (b) Optimum limefly ash ratio yielding maximum strength is 0.75, (c) addition of gypsum accelerates rate of strength gain for compacted fly ash-lime mixtures (d) for 28 days wet burlap curing optimum gypsum content yielding maximum strength is 2% and maximum compressive strength is achieved for lime contents in the range of 10 – 17%, (e) steam curing (at 80 °C for 24 hours) gives highest compressive strength for compacted fly ash-lime mixtures. Characteristics of compacted fly ash-lime, fly ash-lime-gypsum and fly ash-cement bricks and their masonry are presented in chapter 4. Compressive strength, elastic modulus, water absorption, initial rate of absorption, dimensional stability and durability of the bricks were examined. Compressive strength, flexure bond strength and stress strain relationship for the fly ash brick masonry using cement-lime mortar were evaluated. The investigations clearly show the possibility of producing bricks of good quality using compacted fly ash-lime gypsum mixtures. Wet compressive strengths of 8- 10 MPa was obtained for compacted fly ash-lime-gypsum bricks at the age of 28 days. Wet strength to dry strength ratio for these bricks is in the range of 0.55 – 0.67. Initial tangent modulus for the fly ash-lime-gypsum bricks in saturated condition is in the range of 8000 – 12000 MPa. There is a large scope for selecting optimum mix ratios of fly ash, sand, lime and other additives to obtain a specific designed strength for the brick. The thesis ends with Chapter 5 highlighting major conclusions of the investigations.

The aim of the diploma thesis is design an area of a horseback riding club in the village Tereziny Dary in form of project documentation. The area will be used for comfortable housing of small amount of horses and their training for military competition. There are an accommodation for staff, an accommodation for guests, a meeting place for club´s members, a stable for horses, an outdoor riding school and an indoor riding school in the area. For purpose of the thesis the building SO01 – Club Facilities was processed in detailed design documentation. The buildings SO02 – Stable and SO03 – Indoor Riding School were processed in architectural study documentation.

Les éléments séparatifs à base de plaques de plâtre (cloisons, bloc-porte…) sont d’abord destinés à délimiter les espaces à l’intérieur d’une construction. Ils contribuent aux exigences essentielles pesant sur l’ouvrage en termes de sécurité en cas d’incendie, d’isolation thermique et acoustique. La réglementation française stipule que la vérification de la résistance au feu des ces éléments doit être vérifiée par des essais en vraie grandeur menées selon des procédures normalisées et qui sont souvent onéreux pour les industriels. De plus, la limite du four (5 m de hauteur et 7 m de largeur actuellement) pose un problème pour les fabricants quand ils veulent valider des cloisons plus grandes. Par conséquent, la tendance industrielle est de développer une méthode prédictive du comportement au feu des éléments séparatifs. Cette thèse présente une étude dans le cadre du projet de recherche de EFECTIS France, ce qui conduit à l'élaboration d'un modèle numérique capable de prédire le comportement thermo-mécanique des cloisons en plaques de plâtre se composant d’une ossature métallique vissée sur des parements en plaques de plâtre, quand elles sont soumises à une action thermique normalisée de EN 1363-1 sur une face. Dans cette étude, on présente d’abord des programmes d’essais qui permettent d’une part, d’identifier les propriétés thermo-physiques et thermo-mécaniques de plaques de plâtre cartonné, à température ambiante et à haute température, et d’autre part de caractériser la liaison cinématique de la fixation par vissage des parements en plaques de plâtre sur les montants acier de l’ossature interne, à température ambiante. En suite, on présente le développement des modèles thermique et mécanique avec le logiciel CAST3M en utilisant les paramètres mesurés lors des programmes d’essais sur les matériaux et les assemblages. Les modèles développés permettent de prendre en compte : (i) les phénomènes de transfert thermique par conduction, rayonnement et convection au travers d’une cloison - (ii) la chute du parement exposé de la cloison pendant l’essai - (iii) le comportement mécanique de la cloison elle-même, c'est-à-dire le comportement thermo-mécanique de ses éléments constitutifs (plaques de plâtre cartonné et montants métalliques) ainsi que celui des assemblages vissés des plaques de parements sur les montants d’ossature. / The fire resistance of building elements (partition walls, door sets ...) by means of tests according to standard procedures is often expensive for manufacturers. In consequence, Efectis France is conducting a specific research project aiming to develop an efficient and economical tool in order to carry out the preliminary design of new products as well as their optimization and extend the application of experimental results to configurations different from those of the test (change of size, of component, of boundary conditions ...). This thesis presents a study in the scope of above research project, which led to the development of a numerical model capable of predicting the thermo-mechanical behavior of separating elements such as flexible partitions made with internal steel studs and plasterboard facings, when they are subjected to standard thermal action of EN 1363-1 on one side. This study is organized in three steps. The first one is an experimental investigation relative to the characterization of thermo-physical and of thermo-mechanical properties of plasterboards used in above mentioned partition walls. In the second step, a specific numerical model for the analysis of plasterboard partition fire behavior is developed. This model allows treating not only nonlinear heat transfer but also the nonlinear structural behavior of the partitions from thermal stresses taking into account the degradation of rigidities for the punctual screwing of plasterboards on the steel studs. In the third step, the prediction of the numerical model is compared with experimental results in terms of temperature and displacements of the partitions. The comparisons enable to show the validity of the numerical model to predict appropriately the fire behavior of plasterboard partitions.

Il est indispensable pour comprendre la diagenèse, i.e., la formation des roches sédimentaires, le durcissement des matériaux de construction hydrauliques comme le ciment ou le plâtre, ou la biominéralisation, d'identifier les mécanismes élémentaires de la cristallisation minérale. Le taux de réaction macroscopique des minéraux est généralement déduit de mesures de chimie des solutions. A côté de ces mesures macroscopiques, l'étude de la réactivité des minéraux inclut maintenant l'analyse des mécanismes atomiques a l'origine des réactions chimiques. Cela a été rendu possible depuis deux décennies par l'apparition d'outils capables d'observer des surfaces avec une résolution nanométrique, tels que la microscopie à force atomique et l'interférométrie à balayage vertical. Le gypse et la calcite font partie des minéraux dits mous. Ce sont des minéraux extrêmement répandus, que l'on peut trouver autant dans la nature sous forme de roches sédimentaires que dans le monde industriel. Le gypse (CaSO4,2H2O) est une évaporite dont les applications incluent la fabrication des plaques de plâtre, l'ajout au ciment Portland comme retardateur, l'élaboration du plâtre de Paris et l'amendement des sols. La sélénite ou l'albâtre sont des variétés de gypse utilisés comme matériaux pour l'ornement, mais leur faible dureté limite leur durabilité. La calcite, forme la plus stable de CaCO3, est un des principaux biominéraux, et un des constituants majeurs des roches des réservoirs carbonates, stockant naturellement de l'eau, du pétrole ou du gaz naturel. Quand les organismes biologiques font croitre leur coquille, ils contrôlent la morphologie, la taille, l'orientation et même la phase des cristaux de carbonates de calcium qui la constituent. Cela conduit à des biomatériaux présentant des propriétés physiques et chimiques qui diffèrent significativement de ceux de la calcite inorganique. Une connaissance plus approfondie des mécanismes sous-jacents à la réactivité de surface de la calcite et de l'effet des impuretés sur celle-ci permettra de nous rapprocher de la possibilité de synthétiser des minéraux biomimétiques, aux propriétés comparables à celles de la calcite biogénique. Dans ce contexte, ma thèse s'est développée dans trois directions. Dans la première, j'ai étudié l'influence d'une contrainte mécanique sur les mécanismes de dissolution. Mon objectif dans cette partie a été de tacher de déduire le taux de dissolution macroscopique à partir de la cinétique des mécanismes atomiques. La seconde partie de la thèse, la plus conséquente, a consisté à étudier l'influence d'une contrainte mécanique sur la croissance de la calcite, et à sonder le rôle d'un additif organique lors de cette croissance sous contrainte. Dans la troisième partie, je me suis penchée sur la dissolution de cristaux de calcite à l'aide de mesures topographiques quantitatives sur des aires relativement étendues de la surface des cristaux, dans une large gamme de pH. J'ai en particulier étudié l'influence d'un additif organique sur la dissolution et la cinétique de réaction à grande échelle. Les taux de dissolution macroscopique et microscopique, c'est-à-dire déduits de la dynamique d'évènements moléculaires (croissance de piqure d'attaque, migration de marche atomique), ne sont presque jamais en accord, même qualitativement, et l'élaboration d'une théorie générale liant la cinétique du phénomène aux deux échelles est encore en cours. Je présente ici des taux de dissolution microscopique du gypse, mesures par microscopie par force atomique (AFM), en accord quantitatif avec les taux de dissolution macroscopiques. Cet accord inédit a été obtenu en prenant soin de neutraliser le biais induit par le fait que la pointe AFM applique une force sur la surface qu'elle sonde, et en identifiant avec soin les mécanismes moléculaires majeurs à l'œuvre lors de la dissolution...[etc] / Identifying reaction mechanisms of minerals is fundamental to understand diagenesis, i.e, sedimentary rock formation, construction material, like cement or gypsum, hardening, and biomineralization. The macroscopic reaction rates of minerals are generally deduced from solution chemistry measurements. Beside the measurement of macroscopic reaction rates, the study of the reactivity of minerals includes now the investigation of the atomic mechanisms involved in the reactions. This has been made possible for two decades by the use of tools resolving nanometric objects, such as vertical scanning interferometry (VSI) and atomic force microscopy (AFM). Gypsum and calcite are among soft minerals. They are extremely widespread mineral that can be found naturally in sedimentary rocks. They are also used in many industrial fields. Gypsum (CaSO4,2H2O) is an evaporate mineral. Gypsum uses include: manufacture of wallboards, plaster of Paris, soil conditioning, and hardening retarder in Portland cement. Varieties of gypsum known as "satin spar" and "alabaster" are used for a variety of ornamental purposes; however, their low hardness limits their durability. Calcite, the most stable crystalline form of CaCO3, is moreover important as a bio-mineral and a major constituent of host rock in carbonate reservoirs, which host drinking water and natural oil and gas. When biological organisms grow their shells, they control the crystal morphology, size, orientation and even the crystal phase of precipitated calcium carbonate. This results in materials with physical and chemical properties that differ significantly from those of inorganically precipitated calcite. Gaining more insight into the surface reactivity of calcite and the effect of surface impurities will bring us one step closer to being able to synthesize biomimetic material, which mimic the properties of biogenic calcite. In this thesis, I had three main focus points. In the first part I studied the effect of stress on the dissolution mechanisms. I investigated to deduce the dissolution rate from the atomic kinetics. The second and the most extensive was the study of the influence of stress on the calcite growth and probing the role of an organic additive on the dynamics of calcite growth while applying stress. In the third part I emphasised on quantitative topographic measurements of dissolving calcite crystal over a relatively large and fixed view at vast range of pH. I considered the influence of an organic additive on the dissolution and surface reaction kinetics at this larger scale. Both macroscopic and microscopic dissolution rates can also be deduced from the dynamics of molecular events (etch pit growth, atomic step migration), but they hardly ever agree, even qualitatively, and the elaboration of a general theory linking the kinetics at the two scales is still in progress. I presented here microscopic dissolution rates of gypsum, measured by atomic force microscopy (AFM), in quantitative agreement with macroscopic rates. This agreement has been obtained in taking care to neutralize the bias induced by the force applied by the AFM tip on the surface, and to identify clearly the driving molecular mechanism. The force applied by the AFM tip on the surface has been seen to increase the solubility of the mineral, thereby introducing a bias, so I have always worked with a constant and low applied force. This result shows that the determination, among the topographic changes during the dissolution of a mineral, of the dominant one, and the measurement of its dynamics, may permit deducing from AFM experiments a reliable macroscopic dissolution rate. The transformation of loose grains into a cohesive solid requires the crystallites to grow eventually constrained by the surrounding grains. Whereas never measured, this confinement and the associated stress is expected to influence noticeably the growth, and the final properties of the material… [etc]

Filmes de água cobrem a maior parte das superfícies em condições ambientes. O estudo dessas interfaces é crucial em biologia e em ciência dos materiais. No entanto, o completo entendimento da adsorção da água e de suas complexas redes de ligações de hidrogênio ainda não foi alcançado. Somente recentemente possuímos técnicas com a sensibilidade e seletividade para estudar estas superfícies até a última camada atômica. A espectroscopia por geração de soma de frequências (SFG) é uma técnica óptica não linear que fornece o espectro vibracional de moléculas em interfaces, sem contribuição do volume do material. A técnica SFG foi utilizada para estudar a estrutura interfacial das moléculas de água estrutural na face livre (010) do cristal natural gipsita (CaSO4 2H2O) e a adsorção de água na mesma à temperatura ambiente. Os espectros SFG na face livre (010), em atmosfera inerte, apresentaram um arranjo com anisotropia azimutal das moléculas de água estrutural com a presença de grupos OH ligados à superfície e grupos OH livre sem formar ligação de hidrogênio, apontando para fora da superfície. O arranjo anisotrópico das moléculas na face (010) é diferente daquele para as moléculas de água no volume do cristal. A adsorção de água foi estudada em equilíbrio com vapor de água em vários valores de umidade relativa. A água adsorvida na gipsita (010) também apresenta um arranjo anisotrópico, porém, diferentemente da água estrutural na superfície livre do cristal, esta apresenta um menor grau de ordenamento e suprime consideravelmente a presença de grupos OH livre. Os resultados experimentais são analisados em conjunto com simulações por dinâmica molecular ab initio realizadas por colaboradores. As simulações apresentaram boa concordância qualitativa e quantitativa com os resultados experimentais, permitindo fazer a atribuição dos espectros vibracionais experimentais, e fornecendo informações difíceis de se obter dos experimentos, como a distribuição orientacional das moléculas de água na interface e sua dinâmica de difusão espacial. / Water films cover most of surfaces under ambient conditions. The study of these interfaces is crucial in biology and materials science. However, a complete understanding of water adsorption and its complex hydrogen bonding networks has not yet been achieved. Only recently we have techniques with the sensitivity and selectivity to study these surfaces to the last atomic layer. Sum-frequency generation (SFG) is a non-linear optical technique that provides the vibrational spectrum of molecules at interfaces, without contribution from the bulk. This technique was used to study the interfacial structure of neat (010) face of Gypsum (CaSO4 2H2O) single crystals and water adsorption on the (010) face at room temperature. The SFG spectra for the neat Gypsum face (010), in inert atmosphere, presented azimuthally anisotropy arrangement of the structural water molecules with the presence of OH groups bound to the surface and free OH groups pointing out of the surface. The arrangement of water molecules on the face (010) is anisotropic but different from that of the water molecules in the bulk crystal. Water adsorption was studied in equilibrium with water vapor at several values of relative humidity. The adsorbed water also exhibited an anisotropic arrangement, however, unlike the structural water, it presents a lower ordering and the free OH groups are strongly suppressed. The experimental results are analyzed together with ab initio molecular dynamics simulations performed by collaborators. The simulations presented good qualitative and quantitative agreement with the experimental results, elucidating the assignment of the experimental vibrational spectra and yielding information that would be difficult to get from the experiments, such as the orientational distribution of interfacial water molecules and their spatial diffusion dynamics.

Made available in DSpace on 2017-07-21T14:19:22Z (GMT). No. of bitstreams: 1 Valter Luis.pdf: 3516533 bytes, checksum: d498d5c67dd1b9a837a128c20cabef67 (MD5) Previous issue date: 2015-02-26 / The interestingness area of data mining process aiming to reduce the amount of models to be analyzed for experts in the interpretation step of the knowledge discovery in databases. In this work, a method for analysis the interestingness of regression models was developed. This method combine probabilistic multivariate models with Pearson correlation test and Wilcoxon signed-rank test resulting in a new interestingness measure, named Impact. The developed method was applied over regression models found during a data mining process for estimating agricultural gypsum requirements. The results showed that the probabilistic multivariate filter was able to filter the best models according to a utility-based approach, in this case, for practical application on agriculture. Six models were considered interesting, with Impact score > 0.5, and only one was miscategorized. On the other hand, the combined statistical test filters were able to filter six models two of them were miscategorized. The attributes identified as most relevant to estimate gypsum rate were: time, Ca and its concentration on effective cation exchange capacity (CaCTCe), mainly in superficial layers. / A interessabilidade de regras é uma área da mineração de dados que tem por objetivo reduzir a quantidade de modelos a serem analisados por especialistas na etapa de interpretação do conhecimento descoberto em bases de dados. Embora existam várias medidas de interesse de regras voltadas para as tarefas de associação e classificação, observa-se uma falta de métodos consolidados para análise de interessabilidade de modelos de regressão. Neste trabalho foi desenvolvido um método para analisar a interessabilidade de modelos de regressão, o qual combina um filtro baseado em modelos probabilísticos multivariados com filtros baseados em testes estatísticos de correlação de Pearson e de postos de sinais de Wilcoxon, resultando em uma nova medida de interessabilidade denominada Impacto. O método desenvolvido foi aplicado sobre modelos de regressão encontrados no processo de mineração de dados para estimativa de gesso agrícola. Estes dados resultam de três experimentos sob Sistema Plantio Direto realizados na Região dos Campos Gerais, PR, nos quais foram medidos, em diferentes épocas, os teores dos nutrientes do solo após a aplicação de doses de gesso. Os resultados mostraram que o filtro probabilístico multivariado foi capaz de filtrar os melhores modelos segundo uma visão de utilidade, ou seja, de potencial de aplicação agronômica. Foram selecionados seis modelos com score de Impacto > 0,5, ou seja, considerados interessantes, e destes apenas um foi considerado incorretamente classificado. Por outro lado, os filtros baseados em testes estatísticos foram capazes de filtrar seis modelos sendo que dois deles podem ser considerados incorretamente classificados. Os atributos identificados como mais relevantes para o problema do gesso agrícola foram a época, o teor de Ca e a concentração de Ca em relação à capacidade de troca catiônica efetiva (CTCe), especialmente em camadas superficiais do solo.