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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Research dilatometer testing in sands and in clayey deposits

Tsang, Clifford Hing-Cheung January 1987 (has links)
The development of Marchetti's flat dilatometer, method of testing, changes of Marchetti's (1980,1981) original correlations and Schmertmann's (1982,1983) proposed correlations are briefly described. Factors affecting results of the dilatometer test (DMT) are discussed. In order to improve the understanding of the Marchetti dilatometer test (DMT), an electronic research dilatometer was developed at UBC. The research dilatometer can measure; pore pressure at the center of the membrane, membrane displacement, applied pressure, pushing force and verticality. Test results obtained from the research dilatometer in sand and in clayey deposits at 4 sites in the Lower Mainland of B.C. are presented. Soil parameters interpretated using Marchetti's (1980,1981) and Schmertmann's (1982,1983) correlations are discussed. Comparison is made to other in-situ testing methods such as cone penetration test, vane shear test and pressuremeter test. Based on a better understanding of the DMT, future potential methods of improving or checking the existing correlations are proposed. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
262

Modelagem e caracterização de uma jazida de areia do município de Igarassu-PE

Silva, Michel Willyam Paixão da 14 August 2014 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-04-18T13:03:33Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Michel Paixão.pdf: 4191711 bytes, checksum: b9cc45fd257ab37fa57ba808c5bb5732 (MD5) / Made available in DSpace on 2016-04-18T13:03:33Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Michel Paixão.pdf: 4191711 bytes, checksum: b9cc45fd257ab37fa57ba808c5bb5732 (MD5) Previous issue date: 2014-08-14 / CAPEs / Este trabalho apresenta a modelagem e caracterização de uma jazida de areia e analisa a viabilidade técnica da mesma, para que a areia seja utilizada como agregado para construção civil. A jazida mineral está localizada às margens da rodovia federal BR-101, à noroeste do município de Igarassu, região metropolitana do Recife-PE e pertence a uma mineração local. Primeiramente, foi realizada uma pesquisa mineral no local do depósito, através de levantamentos geológicos, levantamentos topográficos e sondagens, para cubagem do mesmo. Em seguida, foram efetuadas várias análises físicas e químicas das características do material a ser extraído, tais como: caracterização e qualidade, análises granulométricas, análise química semi-quantitativa e análise de difração de raios-X. Na sequência, foi executada a modelagem geológica do corpo mineral, através do software DATAMINE STUDIO 3.0, para avaliar o seu potencial, sua dimensão e a viabilidade da lavra. Além disso, foram fornecidos subsídios para a elaboração de um projeto do empreendimento mineiro a ser implantado: lavra, carregamento e transporte, beneficiamento (com uma unidade de classificação) e os principais equipamentos necessários para este empreendimento. A partir dos resultados obtidos, constatou-se a viabilidade da areia para ser utilizada como agregado miúdo na construção civil, com a necessidade do tratamento prévio da mesma para se adequar as normas da ABNT, e obteve-se um volume médio de cerca de 7,5 milhões de metros cúbicos, ressaltando a exequibilidade da exploração da jazida com uma vida útil de aproximadamente 60 anos, para uma produção média de 25.000 m³/mês. / This work presents the modeling and characterization of a sand mine and analyze the technical feasibility of the same, so that sand be used as aggregate for civil construction. The mineral deposit is located on the edge of federal highway BR-101, to the northwest of the city of Igarassu, metropolitan area of Recife-PE and belongs to a local mining. First, a mineral survey was conducted at the site of deposit, through geological surveys, topographical surveys and drilling to cubage the same. Then, they were made several physical and chemical analysis of the characteristics of the material to be extracted, such as: characterization and quality, granulometric analyses, semi-quantitative chemical analysis and diffractometry analysis of X-ray. Following, it was executed the geological modeling of the mineral body, through datamine STUDIO 3.0 software to assess their potential, their dimension and viability of the mining operation. In addition, subsidys were provided for the elaboration of a mining project design to be implemented: mining, loading and transportation, beneficiation (with a classification unit) and the main equipment needed for this project. From the results, the feasibility of sand was found to be used as kid aggregate in civil construction, with the need for pretreatment of the same to suit the ABNT, and obtained an average volume of about 7,5 million cubic meters, emphasizing the exequibility of deposit exploration with a lifespan of about 60 years, to an average production of 25,000 m³/month.
263

A study of the sands of Virginia

McGauhey, Percy Harold, Hartman, W. T. January 1929 (has links)
M.S.
264

Crab-Like Dactyl Testing in Two Beach Sands and Play Sand

Ries, Emma Murphy 23 May 2022 (has links)
No description available.
265

Treatment of USU Dairy Wastewaters by Lagoon Intermittent Sand FIltration

Claus, Eric M. 01 May 1980 (has links)
A study of the feasibility of lagoon-intermittent sand filter treatment of dairy wastewaters from the Utah State University dairy was performed from 1978 through 1980. The report also includes an analysis of alternative dairy wastewater treatment systems utilizing a computer model. A simple and inexpensive method of dairy wastewater treatment is needed so that the small (50- 300 cows) dairy farmer can meet the 30 mg/ ~ of BODs federal effluent standard and still earn a profit. The influent to the USU dairy treatment system, the lagoon effluent and the filter effluent were sampled during the summers of 1978 and 1979 for BOD s , suspended solids and volatile suspended solids . The data show t hat removal efficiencies over 90 percent were achieved by the lagoon-intermittent sand filter system, but the effluent BODs and suspended solids concentrations did not meet the federal standards. The high effluent concentrations were a. result of the lagoon being overloaded. The treatment system's construction allowed runoff, groundwater and milking center washwater to enter the lagoon causing greater than expected hydraulic and organic mass loading rates. Despite high influent concentrations the intermittent sand filters consistently removed 80 percent of the suspended solids from the lagoon effluent. If the quality of the lagoon effluent were improved by reducing the organic mass loading rate, the effluent from lagoon intermittent sand filter treatment of dairy wastewaters would meet the federal standards.
266

Geologic Controls of Sand Boil Formation at Buck Chute, Mississippi

Martin, Seth M 13 December 2014 (has links)
Sand boil formation due to underseepage is a potential failure mechanism for levees in the Lower Mississippi River Valley. Sand boils were identified in the Buck Chute study area in the 1990s during high water events and during the 2009 Flood. The site is unique due to the presence of point bar and abandoned channel deposits. To understand the role of these alluvial deposits on sand boil formation at the site, a geologic investigation of the subsurface was conducted. Using shallow geophysics, cone penetrometer tests (CPT), borings, and a geographic information system (GIS), it was concluded that the thin blanket associated with point bar deposits, abandoned channel deposits causing a blocked seepage path, and head differential changes caused by the Muddy Bayou Control Structure were the controls of sand boil formation at Buck Chute.
267

<strong>AN EXPERIMENTAL  STUDY OF THE BASE AND SHAFT RESISTANCE OF PIPE PILES INSTALLED IN SAND</strong>

Kenneth Idem (16032893) 07 June 2023 (has links)
<p> The base and shaft resistance of steel pipe piles installed in silica sand is affected by several factors; these include but are not limited to: shaft resistance degradation, shaft surface roughness, installation method, pile geometry, soil density and particle size, and setup.  This thesis focuses on the first four factors, while also considering the effect of soil density within each factor. Several of the pile design formulas available do not consider the effects of shaft resistance degradation due to load cycles during installation of jacked and driven closed-ended pipe piles, plug formation and evolution during driving of open-ended pipe piles, the degree of corrosion or pitting corrosion on the shaft surface of a pile and its potential impact on setup, and the geometry of the tip of the pile. To assess the impact on pile capacity of some of these factors, a series of static compression load tests were performed in a controlled environment in a calibration chamber with a scaled down instrumented model pile. The air-pluviation technique with different combination of sieves assembled in a large-scale pluviator was used to prepare F-55 sand samples of different density in the calibration chamber. Slight changes were made to the experimental setup to study each factor: sand sample density, driving energy, mode of installation, and geometry and shaft roughness of the model pile.</p> <p><br></p> <p>The results from the experiments confirmed that each of these factors affects the pile resistance. Some of the important conclusions were:</p> <p><br></p> <p>i. The shaft resistance of the model pile is about 2.4 times greater for jacked piles than for driven piles in dense sand, due to the greater shaft resistance degradation in driven piles. </p> <p>ii. Despite the effect of degradation, the shaft resistance of the non-displacement model pile which had no loading cycles was a ratio of 0.37 to that of the driven model pile in medium dense sand and 0.60 in dense sand, due to the absence of displacement.</p> <p>iii. An increase in the surface roughness of the jacked model piles from smooth to medium-rough resulted in an increase of the shaft resistance, which had a ratio of 7.75 to the smooth pile in dense sand and 3.05 in medium dense sand. An increase from smooth to rough resulted in an increase of the shaft resistance, which had a ratio of 8.00 to the smooth pile in dense sand and 4.26 in medium dense sand.</p> <p>iv. Although rougher interfaces produce greater interface friction angles than smooth interfaces with sand, once a limiting value of surface roughness is reached, shearing occurs in a narrow band in the sand in the immediate vicinity of the model pile, with the shaft resistance depending on the critical-state friction angle of the sand. This means the shaft resistance will not increase further with changes in pile surface roughness, due to the fact that the internal critical-state friction angle of the sand has been reached in the shear band during loading.  </p> <p>v. During installation, the conical-based pile had a higher penetration per blow compared to the flat based pile from 0 to 25.6<em>B</em> in medium dense sand and 0 to 20<em>B</em> in dense sand (<em>B</em> = base diameter). After the pile was installed beyond 25.6<em>B</em> in medium dense and 20<em>B</em> in dense sand, the penetration per blow was identical. </p> <p>vi. The base resistance of a conical-based model pile was about 0.76 times that of a flat-based model pile in dense sand and 0.56 in medium dense sand. </p> <p>vii. Jacked piles had similar base resistance ratio of about 0.93 to 0.95 of driven piles in dense sand and 0.98 to 1.05 in medium dense sand. However, they had a much higher shaft resistance ratio of about 1.67 to 2.07 in dense sand and 1.44 to 1.50 in medium dense sand. </p>
268

"Two Georges and the Dragon"--The Heroine's Journey in Selected Novels of George Sand and George Eliot

Williamson, D.A. 01 1900 (has links)
Missing page 53. / A critical study which links George Eliot to George Sand is not a new idea. While considerations of social thought, art, feminism and the imagery used by the two novelists have formed much of the comparative criticism to date, this study examines another vital link between the French and the British novelist. "Two Georges and the Dragon" focuses on the psycho-spiritual evolution, the individuation process, experienced by four Sand-Eliot heroines. The nineteenth century's concern with "Soul-Making" (Keats, 334 ), its search for self and certitude in the face of social, religious and technological change, fostered a widespread artistic renovation of both pagan and Christian myth. Thus, while Carl Jung's terminology for the stages of individuation was not yet available to either Sand or Eliot, the mythic archetypes essential for a Jungian exploration of the psyche were. It is from this archetypal perspective that the sequence of "the -heroine's journey" is developed. Maureen Murdock's The Heroine's Journey (1990) depicts the twentieth century version of the feminine quest for individuation. Despite separation by a century-and-a-half, the Sand-Eliot protagonists' struggles to attain an "informed sympathy'' are strikingly similar to the contemporary "heroine's journey" toward an integrated consciousness. Murdock's archetypal sequence illustrates precisely how "history (becomes] incarnate" in these nineteenth-century heroines. A progression through a series of initiatory stages marks the individuation process. To be sure, some measure of ego deflation and subsequent renewed perspective do occur for many characters in both Sand's and Eliot's novels. In these cases, shadow aspects of the unconscious emerge and are assimilated. However, our concern is with the heroines who undergo a complete cycle of individuation. In Jungian terms, these heroines not only acknowledge personal shadow content, they also undergo an ultimate ego deflation in depth. The process involves an encounter with, and assimilation of, the collective historical values inherent in the imago Dei, central archetype of the psyche's unconscious aspect. As a result of her personal individuation, the heroine, in turn, effects an elevation of consciousness in those around her. George Sand's Consuela offers the nineteenth century's first depiction of a complete individuation process for the feminine. This study proposes that the same process marks the experiences of the heroines in George Eliot's The Mill on the Floss, Romola and Middlemarch. / Thesis / Doctor of Philosophy (PhD)
269

Investigation of Optimum Operating Conditions for Recirculating Sand Filters

Weng, Yonghui 01 1900 (has links)
<p> Recirculating Sand Filters (RSFs) provide a compact method of secondary treatment to septic systems and lagoons, are relatively easy to operate and require little maintenance. Together, these characteristics render RSFs particularly appropriate for small communities and municipalities, as they offer a number of economic and operational advantages over conventional technologies. A preliminary study investigating RSF effluent quality, conducted jointly by McMaster University, the Great Lakes Sustainability Fund (GLSF) and the Ontario Ministry of the Environment (MOE) in 1999-2001, conducted pilot-scale experiments and demonstrated that municipal sewage can be successfully treated year-round by RSFs. The results of the preliminary study recommended that further work be conducted to investigate the selection of media size, dosing frequency, recycle ratio, and hydraulic loading rate. </p> <p> The primary objective of this study was to develop design and operating conditions under Ontario climatic conditions with respect to media size, dosing frequency, recycle ratio and hydraulic loading rate by conducting further pilot-scale studies. Three pilot-scale RSFs, operating in parallel, were loaded intermittently with septic tank effluent to evaluate the above mentioned operating parameters on the removal of total suspended solids (TSS), 5-day carbonaceous biochemical oxygen demand (cBOD5), total ammonia-nitrogen (TAN) and total nitrogen (TN). The addition of alum was also implemented to evaluate the removal of total phosphorus (TP). The effluent objectives for this study were based on the MOE general secondary treatment level requirements of monthly averages based on a minimum of four weekly samples. The four-phase experimental program began in April, 2004 and ended in June, 2005. Three media sizes were investigated, with d10 of 2.6, 5 and 7.7 ·mm. The applied hydraulic loading rates were 0.2 and 0.4 rnlday. Dosing frequencies of 24 and 48 times/day were observed. Recycle ratios of 300% and 500% were also evaluated. </p> <p> It was found that the RSF operating with 2.6 mm media, 500% recycle ratio and 24 times/day dosing frequency under a hydraulic loading rate of 0.2 rnlday produced the best quality effluent, and achieved the effluent objectives required by the MOE. These operating criteria, however, must still be investigated under cold weather conditions to ensure acceptable year-round performance in Ontario. With proper addition of alum, the TP effluent objective was achieved under the optimum operating conditions. </p> / Thesis / Master of Applied Science (MASc)
270

L'héroïne et la symbolique de l'amour dans trois romans de George Sand

Iezzoni, Nadia. January 1998 (has links)
No description available.

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