Includes bibliographical references. / 1 v. : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis investigates the nature and origins of minerals of a group known as layer (sheet) silicates or phyllosilicates. It consists of a collection of research papers grouped into 3 categories: modulated layer silicates, clay silicates and the weathering of rocks and minerals, including the formation of clay minerals. Central to the research has been the use of X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). All three research categories were carried out simultaneously. / Thesis (D.Sc.)--University of Adelaide, Dept. of Geology and Geophysics, 1999

No description available.

Includes bibliographical references. / 1 v. : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis investigates the nature and origins of minerals of a group known as layer (sheet) silicates or phyllosilicates. It consists of a collection of research papers grouped into 3 categories: modulated layer silicates, clay silicates and the weathering of rocks and minerals, including the formation of clay minerals. Central to the research has been the use of X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). All three research categories were carried out simultaneously. / Thesis (D.Sc.)--University of Adelaide, Dept. of Geology and Geophysics, 1999

No description available.

Soil clays relatively high in montmorillonite were examined and compared to the reference material. / Master of Science

A planície do Recife apresenta origem flúvio-marinha, depósitos de argilas moles que se espalham em mais de 50% de sua área, tornando-se um cenário propício para a ocorrência de recalques diferenciais em bases e fundações de construções diversas assentadas sobre esses depósitos. A presente dissertação trata de uma investigação geotécnica em uma argila orgânica mole no bairro de Chão de Estrelas na cidade do Recife. Nesse local foram retiradas amostras indeformadas das margens do rio Beberibe que resultaram em parâmetros de compressibilidade utilizados como referência na realização de um projeto viário para o bairro. Este trabalho utiliza dessas mesmas amostras para realizar uma complementação desse primeiro estudo. Ademais, um vasto acervo de referências bibliográficas sobre a compressibilidade de solos moles deu suporte. O objetivo geral é a análise da compressibilidade de uma argila orgânica mole através dos ensaios de adensamento com drenagem vertical e radial; e, especificamente, estudar a influência da secagem prévia na obtenção da umidade das amostras; analisar a qualidade das amostras estudadas e propor a correção da curva de compressibilidade de campo; comparar seus resultados ou parâmetros de compressibilidade aos resultados já catalogados para o mesmo local da pesquisa e, de um modo geral, para a planície do Recife; obter valores mais precisos para a tensão de pré-adensamento; e, analisar parâmetros de compressibilidade de uma amostra completamente amolgada em laboratório com outra amostra indeformada de boa qualidade de mesma referência e profundidade. Para tanto, a pesquisa se utilizou de cinco amostras retiradas de duas Ilhas, termo esse que se refere a uma região estudada, ou seja, aos furos de sondagem 203A e 208A, respectivamente, Ilha 1 e Ilha 2. Da primeira foram retiradas amostras em três profundidades; enquanto a segunda ilha proporcionou amostras em duas profundidades; sendo executados dois ensaios de adensamento por profundidade, cinco por drenagem vertical e cinco por drenagem radial. Foi realizado também um outro ensaio de adensamento com drenagem vertical em amostra completamente amolgada em laboratório, totalizando assim 11 ensaios de adensamento. Em todos esses ensaios realizados foram utilizados incrementos de tensão menores que a tensão anterior, (Δσ/ , apenas na região que antecede a compressão virgem, de maneira a melhor definir a tensão de pré-adensamento. Os resultados dos parâmetros de compressibilidade encontrados na pesquisa estão em conformidade com a literatura. As formas das curvas de compressibilidade e parâmetros apresentados pelos ensaios de adensamento vertical e radial se mostraram semelhantes. O índice de plasticidade sofreu influência da secagem prévia do material. Os valores das tensões de pré-adensamento se apresentaram mais próximos em comparação aos primeiros estudos que embasaram o projeto viário no bairro de Chão de Estrelas no Recife. Foi demonstrado também que, pela reconstrução da curva de compressibilidade do campo, as amostras, mesmo as de boa qualidade, sofrem um percentual de amolgamento. / The origin of Recifes plain is riverine and marine. Deposits of organic soft clay are spread in more than 50% of its area, which creates a favorable scenery for a occurrence of differential repression in several constructions foundations localized over these deposits. The present work treats of a geotechnical investigation of the a soft organic clay of the Chão de Estrelass neighborhood. In this location many not deformed samples of this material were taken in the Beberibe riverside margins that resulted in parameters of compressibility used as reference in the accomplishment of a road project for the neighborhood. This research, however, used the same soft organic clay samples of the Chão de Estrelass neighborhood to accomplish a complementation of that first study. Besides, a vast collection of literature references on the compressibility of organic soft clay gave support to this study. The general objective this thesis is the analysis of the compressibility of a organic soft clay through of the vertical or radial drainage oedometer test; and, specifically, to study the influence of the preview drying these materials in the obtaining of the natural humidity these samples; to analyze the quality of this organic soft samples clays and to propose the correction of the field compressibility graph lines; to make a comparison between the fists studies results or compressibility parameters already classified and the news complements results by this work, and, in general, with results found in the plain of Recife city; to find accurate value to the pre-compression stress; and, to analyze the results of the compressibility parameters of the a unstructured sample with the results of the a structured sample in the same condition e depth. To achieve those goals, the research used five samples taken from two islands, this term refers to a region studied, called Island 1 e Island 2, respectively, referring of the borehole 203A e 208A. Of the Island 1 were taken in the three depths; while on the second Island were taken in the two depths; being executed two drainage rehearsals by each depth, five vertical drainage rehearsals and five radial drainage rehearsals. It were still accomplished for another vertical drainage rehearsals with a unstructured organic soft clay sample, totalizing 11 rehearsals. In all those rehearsals were used small adjustment or increments of the stress, always using less stress that the before stress, (Δσ/ , only in the area that precedes the virgin compression, way to define the best pre-compression stress value. The results of the compressibility parameters found in this work are in accordance with the literature values. The forms of the compressibility curves and the compression parameters values by the vertical and radial drainage rehearsals are shown similar. The plasticity index suffer influence of the previous drying of the material. The value of the pre-compression stress came closer in comparison with the results of the first study that based the road project for the Chão de Estrelass neighborhood. This work demonstrated by the reconstruction of the curve of compressibility of the field that good quality organic soft clay sampless suffer some percentual of the unstructured situation.

M.Tech. (Extraction Metallurgy) / Please refer to full text to view abstract

No description available.

This project was an attempt to deter:nine haw the plasticity of clays and limes, as determined by the Whittemore Plasticimeter, varied over a range of water contents. The performance tests showed that the Plasticity Figure depends on the load applied to the shaft and on the size of the sphere. Furthermore the position of the zero-setting has an important effect on the results of a test. For one clay body, containing Tenn. Ball no. 5, there was a plastic range, at the working consistency of the clay, within which the Plasticity Figure remained constant. For another clay body, containing Challenger Ball, the Plasticity Figure decreased at a steady rate with increase in water content. For both clay bodies the one minute travel was found to be approximately proportional to the water of plasticity. The plasticimeter was found to be applicable to testing limes providing all the load was removed. Two Ohio Whites and one mason's hydrate were tested. In general, the Plasticity Figure was inversely proportional to, and the one minute travel directly proportional to the water content. The Ohio Whites required 15 per cent less water to reach the testing consistency than the ma.son's hydrate, and had Plasticity Figures, at that point, twice as great. A variety of clays were tested and Plasticity Figures obtained for both de-aired samples and those not de-aired. The results of typical tests were expressed on a flow diagram. / M.S.

No description available.