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Thermal Conductivity of Soils from the Analysis of Boring LogsPauly, Nicole M. 21 October 2010 (has links)
Recent interest in "greener" geothermal heating and cooling systems as well as developments in the quality assurance of cast-in-place concrete foundations has heightened the need for properly assessing thermal properties of soils. Therein, the ability of a soil to diffuse or absorb heat is dependent on the surrounding conditions (e.g. mineralogy, saturation, density, and insitu temperature). Prior to this work, the primary thermal properties (conductivity and heat capacity) had no correlation to commonly used soil exploration methods and therefore formed the focus of this thesis.
Algorithms were developed in a spreadsheet platform that correlated input boring log information to thermal properties using known relationships between density, saturation, and thermal properties as well as more commonly used strength parameters from boring logs. Limited lab tests were conducted to become better acquainted with ASTM standards with the goal of proposing equipment for future development.
Finally, sample thermal integrity profiles from cast-in-place foundations were used to demonstrate the usefulness of the developed algorithms. These examples highlighted both the strengths and weaknesses of present boring log data quality leaving room for and/or necessitating engineering judgment.
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Liquefaction response of soils in Mid-America evaluated by seismic cone testsSchneider, James A. 08 1900 (has links)
No description available.
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Measurement and Modeling of Anisotropic Spatial Variability of Soils for Probabilistic Stability Analysis of Earth SlopesVan Helden, Michael John 25 April 2013 (has links)
Geotechnical engineering design has relied upon deterministic methods of analysis whereby values for analysis parameters and conditions are selected subjectively based on judgment with the intent of providing acceptable margins of safety. The objective of this research was to improve the use of probabilistic slope stability analysis in practice so that the design of slopes can be made on a consistent and probabilistic basis.
The current research involved the development of a methodology for the measurement and modeling of the anisotropic autocorrelation distance of cohesive soils, which was demonstrated at Dyke 17 West of the McArthur Falls Generating Station.
In-situ testing using the piezocone and laboratory testing was conducted to characterize the spatial variability of the effective-shear strength envelope. Vertical (down-hole) and horizontal (cross-hole) geostatistical analysis was conducted to assess the anisotropy of the semivariogram. The investigation identified that heterogeneous inclusions had significant impacts on the results, but that simplistic (visual) identification and filtering procedures were adequate.
The effective-stress shear strength envelope was statistically characterized as a random field, which was simulated as a first-order Markov process using customized add-in functions in a limit-equilibrium slope stability analysis. The analysis accounts for the spatial variability of shear strength and is capable of simulating both isotropic and anisotropic autocorrelation functions.
The study showed that the critical slip surface geometry and the probability of failure can be significantly different when the anisotropy of spatial correlation is accounted for. The study also showed that neglecting spatial correlation may over-estimate the probability of failure, however this finding was noted to be likely case-specific. The primary conclusion of the study was that appropriate representation of spatial correlation is essential to calculating the probability of failure.
Finally, convergence of the probabilistic simulation was evaluated using bootstrapping of the simulated factor of safety distribution to assess the standard error in the mean factor of safety, standard deviation of factor of safety and the probability of failure. A convergence criterion based on the percentage standard error in the probability of failure was proposed and used to define the number of Monte-Carlo iterations required.
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Post processing of cone penetration data for assessing seismic ground hazards, with application to the new Madrid seismicLiao, Tianfei. January 2005 (has links)
Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2006. / Mayne, Paul W., Committee Chair ; Goldsman, David, Committee Member ; Lai, James, Committee Member ; Rix, Glenn J., Committee Member ; Santamarina, J. Carlos, Committee Member.
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Caracterização da resistência de um solo tropical a partir do ensaio de penetração dinâmica de cone com energia variável (panda) / Resistance characteristics of a tropical soil from a dynamic cone penetration test with variable power (panda)Diemer, Francielle 08 August 2014 (has links)
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Previous issue date: 2014-08-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Get soil resistance is critical to making any geotechnical design with confidence, thus,
laboratory tests are used to determine the strength and deformability of the ground in discrete
points involved in the volume of soil mass. Due to heterogeneity of soil formation is that field
trials are needed to supplement this determination and enrich the bank information. Field trials
were able to identify and estimate the mechanical parameters of the soil, an adequate prediction
of the behavior of retaining structures, excavation, foundation, floor sizing, etc., and determine
the characteristics of the soil profile, and have was used to estimate the mass of strength
parameters involved ground. In this sense a new tool for the characterization of the soil profile
from dynamic penetration of a metal cone with variable energy (PANDA) has been studied to
find a relationship with the strength parameters of a tropical soil obtained in a vertical slope of
about 4, 0 m high, located in Alexânia - GO with sandy visual tactile characteristics. Therefore,
we performed PANDA tests up to 4.0 meters and determining the moisture profile through a
survey to auger up to 3.70 meters and laboratory characterization tests were performed,
determining the strength parameters in natural moisture condition and flooded , deformation
parameters and determination of soil water characteristic curve (CCSA). PANDA the results
were compared with the laboratory tests for this ground and found a range of variation between
them always considering the trials of natural moisture condition. With the results it was possible
to see the influence of suction in the PANDA test. In terms of resistance parameters was
possible to find a friction angle of the relationship with the penetration of energy (qd) for this
soil. Overall the strength parameters showed the same trend as the qd values obtained by
PANDA compared with respect to depth. Finally, with the results it is recommended to carry
out further testing on different soil types in different humidity conditions to improve relations
found and increase the database. / Obter a resistência do solo é fundamental para elaborar qualquer projeto geotécnico com
confiança, sendo assim, ensaios de laboratório são usados para determinar a resistência e
deformabilidade do solo, em pontos discretos no volume da massa de solo envolvido. Devido
a heterogeneidade da formação do solo é que são necessários ensaios de campo para
complementar essa determinação e enriquecer o banco de informações. Os ensaios de campo
são capazes de identificar e estimar os parâmetros mecânicos do solo, para uma adequada
previsão do comportamento de estruturas de contenção, escavações, fundações,
dimensionamento de pavimentos, entre outros, além de determinar as características do perfil
do solo, e têm sido utilizados para estimar parâmetros de resistência do maciço de solo
envolvido. Nesse sentido uma nova ferramenta para caracterização do perfil do solo a partir de
penetração dinâmica de um cone metálico com energia varíavel (PANDA) foi estudado para
encontrar uma relação com os parâmetros de resistência de um solo tropical obtido em um
talude vertical de aproximadamente 4,0 m de altura, localizado em Alexânia – GO, com
características tatil visuais arenosas. Para tanto foram realizados ensaios de PANDA até 4,0
metros e determinação do perfil de umidade através de uma sondagem à trado até 3,70 metros
e em laboratório foram realizados ensaios de caracterização, determinação dos parâmetros de
resistência na condição de umidade natural e inundado, parâmetros de deformação e
determinação da curva característica solo água (CCSA). Foram comparados os resultados do
PANDA com os ensaios de laboratório para este solo e encontrou-se uma faixa de variação
entre eles sempre considerando os ensaios da condição de umidade natural. Com os resultados
encontrados foi possível ver a influência da sucção no ensaio PANDA. Em relação aos
parâmetros de resistência foi possível encontrar uma relação do ângulo de atrito com a energia
de penetração (qd) para este solo. No geral os parâmetros de resistência apresentaram a mesma
tendência que os valores de qd obtidos pelo PANDA quando comparados em relação a
profundidade. Por fim, com os resultados encontrados recomenda-se realizar mais ensaios com
diferentes tipos de solo em diferentes condições de umidade para melhorar as relações
encontradas e aumentar o banco de dados.
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Caracterização preliminar do subsolo da área urbana de Boa Vista-RR, a partir de sondagens de simples reconhecimentoIana Carmem de Souza e Silva Avila 03 December 2007 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O trabalho foi desenvolvido na área urbana de Boa Vista, as variáveis estudadas foram: altitude, nível da água e limite de sondagem objetivando a caracterização preliminar do subsolo de Boa Vista, através de sondagens de simples reconhecimento. Foram utilizados 75 pontos dos quais 47 do banco de dados da
empresa A.P. Engenharia e RC engenharia nos anos de 1994 à 2007 e mais 28 dados levantados durante a pesquisa. Foi realizado a análise multivariada para o conhecimento de padrões não supervisionados as técnicas de Análise de Componentes Hierárquicos confirmados pela Análise de Componentes Principais. Com isto foram identificadas 3 Zonas para a Cidade de Boa Vista: Menos Vulneráveis; Zona 1 - englobando somente o bairro Cidade Satélite e Zona 3 - os bairros Aquilino da Mota Duarte, bairro Centro e seu transecto até o bairro Caçari, bairro Caçari e bairro Paraviana.; Mais vulneráveis: Zona 2 - todos os
bairros localizados após o limite da BR 174, sentido leste, com exceção do Bairro Aquilino da Mota Duarte e os bairro entre a BR 174, Centro, Caçari e Paraviana. A média do Nível de
água (NA) da cidade foi de 6,3m, os bairros com maior curva de nível se enquadraram nos bairros de menos vulnerabilidade; nos pontos Cecília Brasil, Cel Mota, Ig Mirandinha, Av Gen Sampaio registraram NA na superfície; o solo mais resistente foi o ponto Centro SEFAZ, no bairro Centro com limite de sondagem de 1,1m, o solo com menor resistência foi o ponto BR 174 localizado em área de cerrado após a ponte do Cauamé. Após a determinação das zonas menos e mais vulneráveis foi realizada uma análise de granulometria para representar cada zona, que classificou o material do ponto mais vulnerável como areia franca e franco arenoso e para o ponto representante da zona menos vulnerável apresentou a classificação do material como franco argilo arenoso e franco arenoso / Considering all the urban construction of Boa Vista, the following variables had been studied: altitude, water level and limit of probing, objectify the preliminary characterization of the
subsoil of Boa Vista through probing of simple recognition. Had been used 75 point whose 47 were from the data base of the company A.P Engineering and RC engineering in the year of
1994 to the 2007 and more 28 data raise during the research. Was accomplished the analysis of multivary for the knowledge of standard not supervised according to the technique of
Analysis of Hierarchic Component confirm by the Analysis of the Major result. With this 3 Zones for the City of Boa Vista had been identified: Less Vulnerable; Zone 1 - only englobando the Cidade Satelite districts and Zone 3 - the Aquilino da Mota Duarte districts, Centro districts and its transecto until the Caçari districts , Caçari districts and Paraviana districts; More vulnerable: Zone 2 - all the districts located after the limit of BR 174, felt east, with exception of the Aquiline districts of the Mota Duarte and the districts between BR 174, Center, Caçari and Paraviana. The average of the water Level (In) of the city was of 6,3m, the districts with bigger curve of level if they had fit in the districts of little vulnerability; in the points Cecília Brasil, Cel Mota, Ig Mirandinha, Av Gen Sampaio they had registered In the one in the surface; the ground most resistant was the point Center SEFAZ, in the Center districts with limit of sounding of 1,1m, the ground with lesser resistance was located point BR 174 in area of after closed the bridge of the Cauamé. After the determination of the zones and less vulnerable was carried through a granulometria analysis to represent each zone, that classified the material of the point more vulnerable as frank sand and frank arenaceous and for
the representative point of the zone less vulnerable it presented the classification of the material as frank argilo arenaceous and frank arenaceous
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Cattle manure, scalping and soil wetness effects on some physical properties of a hardsetting soil and associated early maize growthNciizah, Adornis Dakarai January 2011 (has links)
Most soils in the Eastern Cape Province, South Africa are shallow and are low in organic matter. Therefore these soils are structurally fragile and highly susceptible to inherent degradative processes like hardsetting. The objective of this study was to determine the effect of cattle manure, scalping and soil wetness on aggregate stability, penetration resistance and early maize growth in hardsetting soils. Glasshouse and field studies were conducted to determine the effect of cattle manure on aggregate stability and penetration resistance of freshly exposed topsoils by scalping at 0, 10 and 20 cm depths. In the glasshouse cattle manure was applied at 0 and 20 Mg/ha and matric suction was kept at ~ 30 and ~ 400 kPa; contrasting high and low soil wetness. Three soils were put in pots and arranged in a randomized complete block 3 2 2 factorial design. The field study was done at the University of Fort Hare research farm and the treatments were arranged in a split-plot complete randomized design with three replications. Scalping treatment was the main plot whilst the quantity of the cattle manure applied was the sub plot. Cattle manure increased mean weight diameter (MWD) by between 48% and 71% under glasshouse and between 18% and 33% under field conditions, depending on the soil wetting rate. Cattle manure reduced MWD when the soil under field condition was subjected to mechanical shaking. Soil penetration resistance decreased linearly, with increasing soil wetness but it rapidly increased with increase in matric suction up to ~200 kPa and thereafter the rate of increase reduced. In the glasshouse, all treatments had no significant effects on shoot dry weight but low matric suction increased root dry weight by 133%. Interaction of cattle manure and low matric suction reduced shoot length by 6%, shoot fresh weight by 25%, root surface area by 36%, root length by 5% and root fresh weight by 29% compared to the control. In contrast, application of cattle manure and high matric suction increased shoot length by 37%, shoot fresh weight by 136%, root surface area by 159%, root length by 94% and root fresh weight by 119%. In the field, cattle manure application increased root length density and shoot dry matter by 26% and 30% respectively. Cattle manure improved the stability of aggregates of the hardsetting soil under rapid or slow water intake conditions experienced during rainfall or irrigation. However, under field conditions cattle manure acted as a deflocculant and decreased the stability of aggregates when mechanical stress was applied. The effectiveness of cattle manure in improving maize growth in hardsetting soils was determined by matric suction.
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Winter rotational cover crops effects on soil strength, aggregate stability and water conservation of a hardsetting cambisol in Eastern Cape Province, South AfricaMupambwa, Hupenyu Allan January 2012 (has links)
Winter rotational cover crops (WRCC) are often used to boost soil fertility and plant nutrition. However, selection and use of WRCC for soil physical improvement is usually overlooked. The objective of this study was to determine the effects of WRCC on soil strength, aggregate stability and water conservation of a hardsetting soil. The soil physical properties were determined after four rotations of growing monocultures of vetch (Vicia dasycarpa cv. Max), lupin (Lupinus angustifolius cv. Tanjil) and oats (Avena sativa cv. Sederberg) and after two rotations of growing bicultures of oats (Avena sativa cv. Pallinup) and vetch (Vicia dasycarpa cv. Max) across two soil layers, 0 to 15 cm and 15 to 30 cm. The individual WRCC and a weedy fallow constituted the treatments in the monoculture study whilst in the biculture study the various combinations of WRCC namely; 90% oat plus 10% vetch (O90V10); 70% oat plus 30% vetch (O70V30) and 50% oat plus 50% vetch (O50V50) and a weedy fallow constituted the treatments. After four rotations with cover crop monocultures, oats significantly (P ≤ 0.05) reduced penetration resistance (PR) whilst vetch increased PR in both soil layers compared to the weedy fallow control. The effect of the biculture treatments was only experienced within the 15 to 30 cm depth. The treatments O50V50 and O70V30 increased the PR compared to the control. The WRCC in monoculture significantly increased the soil aggregate stability relative to the control in both soil layers. Vetch, lupin and oats resulted in a 41.7%; 20.4% and 15.7% increase in MWD in the 0 to 15 cm soil layer and 47.2%; 44.2% and 39.7% in the 15 to 30 cm depth, respectively. An increase in aggregate stability was associated with increased macro-aggregation. Under the biculture, WRCC slightly increased, non- significantly, the aggregate stability. Both hot water and dilute acid extractable polysaccharides showed no significant correlation with aggregate stability in the two studies. Oats monoculture resulted in a significant difference (P ≤ 0.05) on cumulative infiltration compared to the control. However, after 2 h vetch and lupin showed no significant difference from the control on cumulative infiltration. Oats resulted in a 7.8% increase in final infiltration rate (FIR) whilst vetch and lupin reduced FIR by 9% and 16.7% respectively, compared to the control. Bicultures of oats and vetch significantly (P ≤ 0.05) increased cumulative infiltration compared to the weedy fallow control. A similar significant increase in FIR was also observed under bicultures. The treatments O50V50; O90V10 and O70V30 resulted in a 163.3%; 113.3% and 105.4% increase in FIR respectively, compared to the control. Cover crop monocultures significantly (P ≤ 0.05) increased plant available water (PAW) compared to the weedy fallow, with vetch, oats and lupin resulting in a 28.3%; 22% and 23.9% increase respectively, in PAW. However, no significant differences were observed on PAW after two rotations with bicultures. Compared with winter weedy fallow, WRCC improved most of the soil physical properties under study, with the most suitable results expected under bicultures compared to monocultures. Under CA, selection of WRCC like oats, vetch and lupin, one should therefore take into consideration their effects on soil physical properties as a selection criterion and not biomass and fertility alone.
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Correlations and comparisons between the Casagrande liquid limit device and the fall coneKestler, Maureen Anne January 1982 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 275-277. / by Maureen Anne Kestler. / M.S.
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Pore pressures in clays due to cone penetrationLevadoux, Jacques-Noel January 1980 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Vita. / Bibliography: p. 482-499. / by Jacques-Noel Levadoux. / Ph.D.
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