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1
Petroutson, William D., Jeffery B. Bennett, Roderic A. Parnell, and Abraham E. Springer. "Hydraulic-Conductivity Measurements of Reattachment Bars on the Colorado River." Arizona-Nevada Academy of Science, 1995. http://hdl.handle.net/10150/296453.
Повний текст джерелаАнотація:
From the Proceedings of the 1995 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 22, 1995, Northern Arizona University, Flagstaff, Arizona
2
Andrén, Jakob. "An Overview of State-of-the-art Hydraulic Conductivity Measurements in Coarse Grained Materials." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-445699.
Повний текст джерелаАнотація:
Embankment dams are made from soil materials of varying sizes and widely used all over the world.When constructing these, knowing the hydraulic conductivity (K) of the soil materials is a keyparameter in order to construct safe embankment dams. A knowledge gap regarding K measurementsin coarse grained soils has been identified. This thesis aims to provide a theoretical overview ofpresent day state-of-the-art methods for measuring hydraulic conductivity and the controllingcharacteristics for K. Coarse grained soils refers to a soil with the coarsest grain fraction being > 20mm and/or have a K > 10-4m/s. It was found that the fixed wall permeameter is the most suitable laboratory method. In the field, itis possible to estimate K using tracer methods, these however show more potential for leakagepathway detection. Common for all K measurement methods are the controlling characteristics of K,grain size distribution, pore geometry, degree of compaction, particle movement and flow regime.These need to be considered when testing to produce useful measurements. If the relationshipbetween flow velocity and hydraulic head is non-linear, Darcy's law is not valid for calculating K.Fyllnadsdammar är uppbyggda av jord och sprängsten av olika storlekar och finns över hela världen.Att känna till den hydrauliska konduktiviteten (K) av de olika lagren är viktigt för att kunna byggadessa på ett säkert och hållbart sätt. Det har identifierats en bristande kunskap angående K mätningar igrovkorniga jord- och stenmaterial. Målet med denna uppsats är att presentera en teoretisk översikt avden senaste kunskapen inom K mätningar i grovkorniga jord- och stenmaterial och vilka egenskapersom avgör ett materials K. Grovkorniga jord- och stenmaterial syftar till material där den grövstakornstorleken är > 20 mm och/eller har ett K > 10-4m/s. För laboratorie mätningar är en permeameter med en solid vägg den mest lämpliga metoden. Förfältmätningar är det möjligt att mäta K med hjälp av spårämnen, men dessa har mer potential för attupptäcka läckage vägar i fyllnadsdammar. De faktorer som avgör ett materials K ärkornstorleksfördelningen, geometrin av porerna, graden av kompaktering, partikelrörelse ochflödestyp. För att producera mätningar som är användbara behöver dessa faktorer kontrolleras. Omsambandet mellan hydrauliskt huvud och flödeshastighet är icke linjärt kan K inte beräknas genomDarcy´s lag.
3
McKenzie, Colette R. "Measurements of hydraulic conductivity using slug tests in comparison to empirical calculations for two streams in the Pacific Northwest, USA." Online access for everyone, 2008. http://www.dissertations.wsu.edu/Thesis/Spring2008/c_mckenzie_041408.pdf.
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4
Hussen, Akif Ali. "Measurement of Unsaturated Hydraulic Conductivity in the Field." FIND on the Web, 1991.
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5
Hussen, Akif Ali 1957. "Measurement of Unsaturated Hydraulic Conductivity in the Field." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/191170.
Повний текст джерелаАнотація:
Unsaturated hydraulic conductivity was measured using four different methods. Tension permeameters were used to measure unsaturated hydraulic conductivity in the field, using a single disc method, which depends on the measurements of sorptivity, steady state flow rate, initial and final water content (White and Perroux, 1987, 1989). Also, a double disc method was used which utilizes Wooding's (1968) equation for two different disc radii at the same tension for steady state flow rates. Undisturbed and disturbed soil cores were used to measure unsaturated hydraulic conductivity in the lab, using water retention curves with van Genuchten's equations. There were no significant differences in the mean of hydraulic conductivity between single and double disc methods in all the tensions used (0, 5, 10 and 15 cm). There were significant differences between the field methods and undisturbed soil cores in zero cm tension, and disturbed soil cores in 10 and 15 cm tension. The effect of land preparation on the unsaturated hydraulic conductivity was studied using the double disc method. Tilling has significant effects on the unsaturated hydraulic conductivity at all tensions used. The spatial variation of unsaturated hydraulic conductivity and steady state flow in different tensions using the double disc method was studied. We found exponential variogram models for unsaturated hydraulic conductivity at 5, 10 and 15 cm tensions and a random model for zero cm tension. Also, exponential models were best fitted for steady state flow corresponding to pores radii of 0.03 - 0.015 cm, 0.015 - 0.010 cm and steady state flow at 10 cm tension. A Michaelis-Menton model was used for steady state flow at 5 cm and 15 cm tension. Disc permeameters were also used to add 5 cm depth of water, bromide and dye solution at 0, 5, 10 and 15 cm tensions with three replicates. A comparison was made between field data and simulated model under the same boundary and initial conditions as in the field. Results showed that the water and bromide move deeper than the prediction of the simulated model in all tensions used. The differences were larger between simulated model and field data for both water and bromide concentrations in the lower tension and smaller in the higher tension as a result of elimination of some preferential flow paths. An equation was developed for cumulative infiltration valid for both small and large time. The parameters calculated using the developed equation closely matched the measured infiltration, and fit better than a three term series similar to the Philip equation for one-dimensional flow.
6
Lien, Bob Kuochuan 1959. "Field measurement of soil sorptivity and hydraulic conductivity." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/192028.
Повний текст джерелаАнотація:
Four methods were applied at four experimental sites following a two-factor completely randomized design for field soil infiltration measurements at the University of Arizona Maricopa Agricultural Center. The Cassel ring and the disc permeameter at a 2 cm positive head provided saturated measurements whereas the 10 cm and the 5 cm tension disc permeameters provided unsaturated measurements which excluded pores ^ 0.03 and 0.06 cm in diameter, respectively. Sorptivity, hydraulic conductivity and characteristic mean pore size were calculated by the method given by White, Sully and Perroux (1989). Both sorptivity and hydraulic conductivity showed dependence on the method applied. The high sorptivity and hydraulic conductivity values obtained by saturated measurements were associated with the unavoidable presence of root channels and cracks at field hence provided large variation and poor repeatability. On the contrary, the disc permeameter at 5 cm tension demonstrated reliable repeatability and reasonable results.
7
Gomes, Maria Carolina Villaça. "Análise da influência da condutividade hidráulica saturada dos solos nos escorregamentos rasos na bacia do rio Guaxinduba (SP)." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/8/8135/tde-09112012-123744/.
Повний текст джерелаАнотація:
A previsão de áreas suscetíveis a escorregamentos translacionais rasos tem como fundamental etapa a investigação dos fatores condicionantes e dos mecanismos de ruptura. Algumas destas propriedades, como os parâmetros físicos e hidrológicos dos solos, são determinantes para a instabilização de encostas que estão sujeitas a eventos pluviométricos intensos. Uma destas propriedades é a condutividade hidráulica saturada, cujo comportamento pode influenciar no desenvolvimento de poro-pressão positiva ou levar à perda de sucção dos solos, ocasionando rupturas. Desta forma, o objetivo principal desta pesquisa foi analisar a distribuição lateral e vertical da condutividade hidráulica saturada (Ksat) dos solos e sua influência nos escorregamentos translacionais rasos na Serra do Mar (SP). Para tanto, foi selecionada uma bacia representativa da Serra do Mar e nela foram escolhidas três cicatrizes acessíveis e com limites bem preservados para a realização dos ensaios in situ. As profundidades onde foram realizados os ensaios foram definidas a partir da caracterização morfológica dos mantos de alteração nas trincheiras abertas no topo, no centro e na lateral das cicatrizes (0.25, 0.50, 1.00, 1.50, 2.00 e 2.50 m). Finamente, foram realizados os ensaios in situ utilizando-se o Permeâmetro de Guelph, utilizando-se duas cargas hidráulicas H para a que fosse possível calcular a Ksat empregando-se as equações de Richards, Laplace e a análise de Elricket al. (1989), embora tenha sido utilizada esta última para a análise da variação dos valores. A partir dos valores de Ksat, das propriedades físicas dos materiais (distribuição granulométrica, micro e macroporosidade, porosidade total. Além disso, foi analisada a tendência de variação entre 10-4 e 10-7 m/s, predominando da Ksat com a profundidade. Foram obtidos 41 valores de Ksat, os quais variaram entre as ordens de grandeza 10-5 e 10-6 m/s (82,5% dos valores), que mostraram a pequena variabilidade da Ksat nos perfis de alteração investigados, se comparada às diferenças observadas nas propriedades dos solos e corroboram com os trabalhos desenvolvidos na Serra do Mar. Quando confrontado com as propriedades físicas dos materiais (por exemplo, granulometria e porosidade total), observou-se, principalmente, a correlação positiva com a fração areia. De forma geral, foi possível identificar uma tendência de aumento da Ksat com a profundidade, assim como a existência de algumas descontinuidades hidráulicas significativas, tanto de redução quanto de aumento brusco da Ksat em uma pequena profundidade.The prediction of landslides-prone areas has as fundamental step researching controlling factors and failure mechanisms. Some of these properties, such as the physical and hydrological soil properties are crucial to the instability of slopes subject to intense rainfall events. One of these properties is the saturated hydraulic conductivity, whose behavior can influence and lead to the development of positive pore-pressure or the loss of soil suction, causing failures. The main objective of this research was to analyze the lateral and vertical hydraulic conductivity (Ksat) of soils and their influence on shallow landslides in the Serra do Mar (SP). Therefore, we selected a representative basin in the Serra do Mar and there three accessible scars, well preserved, were chosen for in situ measurements. Was also performed the topographical characterization of the scars (slope angle, curvature and orientation and contributing area). The depths where the measurements were performed were defined from the morphological characterization of soil profiles in opened trenches at the top, at the lateral and inside the scars (0.25, 0.50, 1.00, 1.50, 2.00 and 2.50 m). At last, were performed the in situ measurements using the Guelph Permeameter, using two heads H for calculating Ksat using Richards equations, Laplace equations and Elrick et al. (1989) analysis, although the latter has been used to analyze the range of values. From the Ksat values and physical soil properties (e. g. grain size distribution, micro and macroporosity, total porosity) we discussed the role played by them in Ksat values. Moreover was analyzed the trend of Ksat variation with depth. We obtained 41 Ksat values, which varied between 10-4 e 10-7 m/s, mostly among the orders of magnitude 10-5 e 10-6 m/s (82.5% values), that showed the small variability of Ksat in the soil profiles if compared to the observed differences in soil properties, and corroborate with studies developed in the Serra do Mar. When confronted with the physical properties of materials (eg, grain size and total porosity), we observed mainly the positive correlation with the sand content. In general, we observed a tendency of increase of Ksat with depth, as well as the existence of some significant hydraulic discontinuities, both the sudden decrease as the increase in Ksat in a small depth.
8
Špongrová, Kamila. "Design of an automated tension infiltrometer for unsaturated hydraulic conductivity measurement." Thesis, Cranfield University, 2006. http://hdl.handle.net/1826/1420.
Повний текст джерелаАнотація:
A tension infiltrometer for field use, where both water level changes measurement and tension settings could be automated, was built in-house. Differential pressure
transducers were used to automate the water level measurement in the reservoir. The
Mariotte bottle was automated by a set of solenoid valves which were connected via
tubing to pre-defined depths in the Mariotte bottle. Based on design parameters tested in the laboratory (sensor sensitivity, water reservoir diameter, and bubbling
rate) three identical tension infiltrometers connected to a single Mariotte bottle were
built. A new reservoir system made of two plexiglass tubes of different diameter
slotted in each other was found to reduce the measurement fluctuations caused by the
disturbance created to rising bubbles in the reservoir.
The new system was tested on a uniform sandy loam profile prepared in the soil bin
laboratory and different analytical and numerical data analysis methods were
compared. The measured steady state data were used to determine K(h) at different
suctions using the analytical method proposed by Reynolds and Elrick (1991). The
K(h) points obtained were fitted with the van Genuchten’s equation (van Genuchten,
1980) using the RETC program to calculate the best fit parameters Ks, and n. These
parameters were used as initial estimates of the soil hydraulic parameters in the
numerical models HYDRUS 1D and 2D, in which transient cumulative flow data was used to determine the soil hydraulic functions via inverse modelling. The analysis of variance determined significantly higher K(h) values calculated by HYDRUS 1D while the other methods did not differ from each other.
Finally, the tension infiltrometer was used in the field on a sandy loam soil to
characterise five different tillage treatments (conventional plough, shallow plough, minimum tillage, direct drill, and no-tillage). The effect of wheel traffic was also evaluated by measuring the infiltration rates in the wheel-marks. The fully automated
system allowed the measurement of infiltration rates for 8 tensions in triplicate per day with hardly any human intervention apart for refilling the reservoir. The results show that the tillage practices and wheel-traffic have a significant influence on the soil hydraulic function K(h).
9
Murray, Gordon Bruce. "The development of an estimation method for the saturated hydraulic conductivity of selected Nova Scotia soils /." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59983.
Повний текст джерелаАнотація:
An estimation method for predicting the saturated hydraulic conductivity (Ksat) of the soil was developed for common Nova Scotia soil types by examination of historical Ksat records. Detailed statistical analysis was performed to develop useful predictive models for Ksat based on soil physical properties and to determine the confidence limits for specific horizon-soil type combinations. Sensitivity analysis of the Hooghoudt equation was then performed to establish Ksat classes to which the confidence limits could be assigned to complete the development of the estimation method.Model development processes proved unsuccessful due to the influence of factors not considered by the model due to their qualitative nature. Independent field testing of the estimation method with respect to core and Guelph permeameter measurement techniques produced measured values within the same class as the estimated value 34% of the time for both techniques and values within one estimated class or less 70 and 76% of the time for core and permeameter techniques respectively.
10
Johnejack, Kent Robert 1958. "Measurement of saturated hydraulic conductivity with a sealed double ring infiltrometer at Page Ranch, Arizona." Thesis, The University of Arizona, 1992. http://hdl.handle.net/10150/278186.
Повний текст джерелаАнотація:
A sealed double ring infiltrometer (SDRI) was used at Page Ranch, Arizona to measure saturated hydraulic conductivity (Ksat in a test clay pad, as well as to characterize preferential flow and transport mechanisms. Ksat varied from 3.5 x 10⁻⁹ to 2.2 x 10⁻¹⁰ cm/sec depending on treatment of matric potential at the wetting front. These in-situ Ksat values were about one order of magnitude less than the laboratory values that ranged from 10⁻⁷ to 10⁻⁹ cm/sec. Although the pad was not instrumented to detect a shallow wetting front, the dye front and water content data indicated that flow penetrated 4 to 6 cm by the end of the 75 day test. Tracer data suggested that bromide moved to 18 or 20 cm by diffusion and that the effective diffusion coefficient was 15 to 21 x 10⁻¹⁰ m²sec. Preferential flow, as judged by the uniformity of the dye front and bromide tracer movement, was insignificant.
11
Almeida, Eurileny Lucas de. "Measurement of hydraulic conductivity and water retention curves for different methods and prediction of soil physical properties by kriging." Universidade Federal do CearÃ, 2013. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13855.
Повний текст джерелаАнотація:
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoKnowledge of the physical and hydraulic properties of the soil and its spatial dependence is important because it allows you to perform the zoning of the area in plots that receive differentiated management. This work was divided into three chapters whose general objective is to measure the hydraulic conductivity and water retention curve in soil by different methods and by using the Kriging, draw maps of soil physical attributes of the Irrigation Perimeter Baixo AcaraÃ. To obtain the water retention in soil curve method was used filter paper compared to the traditional method in five different soils Perimeter. To measure the hydraulic conductivity were used capacitive sensors to replace the tensiometer in the instantaneous profile installed method on a Argissolo Vermelho Amarelo eutrÃfico , as well as the calibration of these sensors in the field and laboratory. The maps were obtained by kriging of soil properties: sand, silt, clay, soil and particle density, porosity and saturated hydraulic conductivity. To obtain this last the tension infiltrometer and the constant load permeameter were used.
O conhecimento dos atributos fÃsico-hÃdricos do solo e de sua dependÃncia espacial à importante, pois permite realizar o zoneamento da Ãrea em glebas que receberÃo prÃticas de manejo diferenciadas. Este trabalho foi dividido em trÃs capÃtulos cujo objetivo geral à medir a condutividade hidrÃulica e a curva de retenÃÃo de Ãgua no solo por diferentes mÃtodos e, utilizando a Krigagem, elaborar mapas de atributos fÃsicos dos solos do PerÃmetro Irrigado Baixo AcaraÃ. Para obtenÃÃo da curva de retenÃÃo de Ãgua no solo foi utilizado o mÃtodo do papel filtro em comparaÃÃo ao mÃtodo tradicional em cinco diferentes solos do PerÃmetro. Para medida da condutividade hidrÃulica foram utilizados sensores capacitivos em substituiÃÃo aos tensiÃmetro no mÃtodo do perfil instantÃneo instalado em um Argissolo Vermelho Amarelo eutrÃfico, como tambÃm a calibraÃÃo desses sensores em campo e laboratÃrio. Os mapas obtidos atravÃs da Krigagem foram dos atributos do solo: areia, silte, argila, densidade do solo e partÃculas, porosidade e condutividade hidrÃulica saturada. Para obtenÃÃo deste ultimo foram utilizados o infiltrÃmetro de tensÃo e o permeÃmetro de carga constante.
12
Courtois, Nathalie. "Caractérisation de la dispersion en aquifère hétérogène par méthodes de traçages et modélisation stochastique : Application à la nappe alluviale du Drac, à Grenoble." Paris, ENMP, 1999. http://www.theses.fr/1999ENMP0002.
Повний текст джерелаАнотація:
La dispersion à grande échelle en aquifère est principalement dominée par la structure spatiale du champ des perméabilités. L’objectif est ici de caractériser les propriétés dispersives de l’aquifère alluvial du Drac par deux approches basées sur l’utilisation de données expérimentales de traçage. La première approche est classique : des traçages en écoulement naturel sont menés sur un site expérimental comportant 17 puits crépinés sur toute leur hauteur, et permettant une extension maximale de 45m dans l’axe du gradient. La restitution est suivie dans les puits situés en aval, dont la concentration est homogénéisée sur la hauteur. Les paramètres hydrodispersifs sont obtenus par calage de la solution analytique de l’équation de convection-dispersion en 2D sur les courbes expérimentales. La seconde approche consiste à caractériser la variabilité spatiale du champ des perméabilités, pour générer ensuite des champs stochastiques. La distribution verticale des vitesses de Darcy horizontales est mesurée dans les puits par la méthode de dilution ponctuelle, qui est modélisée comme une combinaison de systèmes d’écoulement simples conduisant à une expression analytique. La vitesse de Darcy est alors déduite par calage du modèle sur les courbes expérimentales de dilution, et la perméabilité en découle en supposant un gradient hydraulique moyen sur la parcelle. Ces profils verticaux, menés sur les 17 forages, conduisent à 185 valeurs de perméabilités, moyennées sur 1 mètre. La distribution des perméabilités est supposée suivre une loi de distribution lognormale. La corrélation spatiale est décrite par les variogrammes calculés dans les directions horizontale et verticale. Deux types de modèles de variogrammes sont alors testés : le modèle classique exponentiel, et un autre plus complexe avec ‘effet de trou’ pour simuler la chenalisation. Des champs de perméabilités stochastiques 3D suivant ces deux lois spatiales sont générés à l’aide du logiciel de géostatistique ISATIS, pour être ensuite incorporés dans le code de calcul aux éléments finis CASTEM2000 qui calcule les champs d’écoulement associés. Le transport est modélisé par suivi de particules et technique de Monte-Carlo. Les paramètres hydrodispersifs se déduisent du calcul des moments spatiaux d’ordres 1 et 2 des nuages de particules. Les dispersivités simulées sont alors comparées aux dispersivités déduites des expériences de traçages, et à celles prédites par les théories stochastiques. La dispersivité longitudinale semble avoir atteint une limite asymptotique au terme d’un parcours moyen de l’ordre de la dizaine de longueurs de corrélation horizontaleDispersion in aquifer at large scale is mainly dominated by the spatial structure of the hydraulic conductivity field. The aim of the study is to characterize the dispersive properties of an alluvial aquifer located near Grenoble through two approaches both based on the use of experimental tracing data. The first approach is the classical one: some field-scale tracer tests are conducted under natural gradient on an experimental site which includes 17 fully-penetrating wells. The maximum extent is about 45 meters along the main flow direction. Fluorescent tracers are injected, and their migration is monitored in the restitution wells by sampling device of the volume-averaged concentration. The hydrodispersive parameters are estimated by fitting the classical 2D analytical solution of the advection-dispersion equation on the experimental breakthrough curves. The second approach is to characterize the spatial variability of hydraulic conductivity, in order to generate stochastic fields. The vertical distribution of the horizontal groundwater flow is measured in boreholes by dilution method. This measurement method is modelled as a combination of simple flow structures, which leads to an analytical expression of the tracer concentration versus time. The flow is estimated from the fit of this analytical model on the experimental dilution curves. Hydraulic conductivity is then deduced from the flow through the Darcy’s equation, supposing an average hydraulic gradient on the site. Such vertical profiles on one-meter averaged hydraulic conductivities are conducted in wells to give 185 values on the entire site. The distribution of hydraulic conductivity draws near to a lognormal one, and is assumed to be so in the later generation of stochastic fields. The spatial correlation of the measured data is described by variograms in horizontal and vertical directions. Two types of model are used to fit these variograms: an exponential one, and a more complex model with ‘hole-effect’ in order to simulate channelling. 3D-stochastic hydraulic conductivity fields following these two spatial laws are generated using the geostatistical software ISATIS. These fields are then incorporated in the finite-elements code CASTEM2000 to lead to the associated flow fields. The transport is modelled by particle-tracking and Monte-Carlo techniques. The determination of the first and second order spatial moments leads to the dispersion coefficients. The simulated dispersivities are then compared to the experimental ones, and to the ones predicted by stochastic theories. The longitudinal dispersivity seems to reach an asymptotic limit after a 10 correlation lengths travel
13
Courtois, Nathalie. "Caractérisation de la dispersion en aquifère hétérogène par méthodes de traçages et modélisation stochastique : Application à la nappe alluviale du Drac, à Grenoble." Paris, ENMP, 1999. http://www.theses.fr/1999ENMPA001.
Повний текст джерелаАнотація:
La dispersion à grande échelle en aquifère est principalement dominée par la structure spatiale du champ des perméabilités. L'objectif ici est de caractériser les propriétés dispersives de l'aquifère alluvial du Drac par deux approches basées sur l'utilisation de données expérimentales de traçage.
14
Adams, Amy Lynn. "Laboratory evaluation of the constant rate of strain and constant head techniques for measurement of the hydraulic conductivity of fine grained soils." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/66859.
Повний текст джерелаАнотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 185-187).
This thesis evaluates the constant rate of strain and constant head techniques for measurement of the hydraulic conductivity of fine grained soils. A laboratory program compares hydraulic conductivity measurements made using both measurement techniques on a total of 12 specimens. Both resedimented and intact materials covering a wide range of plasticity are investigated. Specific material types include Boston Blue Clay, San Francisco Bay Mud, Maine Clay, Ugnu Clay and Kaolinite. Constant rate of strain (CRS) and constant head tests were conducted in a standard Trautwein CRS device modified to allow control of the base pore pressure for constant head testing. A flexible wall permeameter device was used to perform constant head hydraulic conductivity testing on two specimens; this allowed for comparison with the constant head measurements made in the CRS device. A bottom seating error was found in the CRS device. Bottom seating error occurs during set up when the top of the base porous stone is not flush with the bottom of the rigid specimen ring, causing a gap to form between the specimen and the porous stone. A bottom seating error translates into a strain error, which affects both the measured CRS compression and hydraulic conductivity results. Bottom seating error can be avoided using a modified set up procedure. Void ratio errors are sometimes noted between the void ratio measured in the CRS device and that measured upon removal from the CRS device. These errors are likely resultant from specimen swelling following load removal. Based on comparison to the results of an interlaboratory study into the reproducibility of the saturated hydraulic conductivity measured in a flexible wall permeameter, the CRS and constant head techniques were found to measure the same hydraulic conductivity. This conclusion is independent of specimen origin, i.e. resedimented or intact. The CRS and constant head techniques measure the same average hydraulic conductivity even when non uniformities are present, provided the non uniformities are continuous and oriented perpendicular to the axial loading direction.
by Amy Lynn Adams.
S.M.
15
Trinh, Viet Nam. "Comportement hydromécanique de matériaux constitutifs de plateformes ferroviaires anciennes." Phd thesis, Université Paris-Est, 2011. http://pastel.archives-ouvertes.fr/pastel-00647893.
Повний текст джерелаАнотація:
Le présent travail étudie le comportement couplé hydromécanique de la couche intermédiaire des plates-formes ferroviaires anciennes. L'objectif principal est de vérifier le fonctionnement des plates-formes sans drainage et d'optimiser les travaux de modernisation de voies anciennes en déblai. Premièrement, les essais d'identification ont été réalisés sur les matériaux prélevés sur le site de Sénissiat. Les résultats ont montré que le sol de la couche intermédiaire de ce site présente une granulométrie bien étalée de 0 à 63 mm et une densité très élevée (d = 2,39 Mg/m3). Deuxièmement, une nouvelle colonne d'infiltration et un moule de compression de 300 mm de diamètre ont été développés permettant d'étudier le comportement hydraulique de la couche intermédiaire. Une faible perméabilité (ks 2,2.10-7 m/s) de cette couche a été estimée à partir des résultats expérimentaux. Troisièmement, une étude expérimentale sur le comportement mécanique de la couche intermédiaire a été réalisée. Cette étude a mis en évidence l'influence marquée de la teneur en eau sur le comportement mécanique de la couche intermédiaire. Un modèle de fatigue avec prise en compte de l'influence du nombre de cycles, du niveau de contrainte appliqué et de l'état hydrique a été élaboré en se basant sur les résultats expérimentaux. Finalement, les mesures de succion, de température et de paramètres météorologiques ont été réalisées sur les plates-formes en déblai sans drainage du site de Moulin Blanc pour compléter l'étude du comportement des plates-formes sans drainage. Une analyse globale des résultats obtenus au laboratoire avec les mesures in-situ a montré que la décision de ne pas mettre en place un dispositif de drainage devra être assortie de justificatifs permettant de s'assurer de la limitation de la teneur en eau de la couche intermédiaire, en se basant sur une étude approfondie sur le cycle d'eau pour chaque site concerné
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Korn, Sandra. "Experimentelle Untersuchung der Wasseraufnahme und der hydraulischen Eigenschaften des Wurzelsystems von sechs heimischen Baumarten." Doctoral thesis, [S.l.] : [s.n.], 2004. http://webdoc.sub.gwdg.de/diss/2004/korn/korn.pdf.
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Zawadzki, Willy. "Data worth of the hydraulic conductivity measurements : slug test and pumping test." Thesis, 1996. http://hdl.handle.net/2429/4726.
Повний текст джерелаАнотація:
The high cost of groundwater remediation is directly related to hydrogeological uncertainty. Of several
parameters responsible for that uncertainty, hydraulic conductivity (K) is the most important, and at the
same time the most difficult to estimate. K can be measured in the lab or field using permeameter tests,
piezocone tests, slug tests and pumping tests. However, the hydraulic conductivities measured with these
tests are not directly comparable because they characterize different volumes of the subsurface. In practice,
one would like to know which method can be used to solve the engineering problem at hand most costeffectively.
For example, is it cheaper from the risk-cost-benefit standpoint to take small-scale
measurements with slug tests, or larger-scale measurements using pumping tests? Which method will
provide greatest reduction in the uncertainty of the hydraulic conductivity field?
I focus on the value of the two most commonly used field techniques, the slug test and pumping test, and
address the problem using an empirical/numerical approach. First I examine the averaging properties of
the pumping test using sensitivity analysis. The pumping-test averaging volume has an elliptical shape,
and its size is proportional to the test duration and to the distance between the pumping well and the
observation well. The averaging exhibits characteristic zonation, with zones behind and in-between the
wells having the strongest impact on the pumping-test scale K. Additionally, the analysis shows the interwell
zone influences the pumping-test K for tests of all duration. While the above mentioned properties of
a pumping-test averaging volume disintegrate with increasing heterogeneity, some characteristic features
can still be distinguished, even for strongly heterogeneous K fields.
Next I develop a data-worth methodology applicable to measurements taken at different scales. The
method relies upon the representation of larger-scale measured parameters as spatially-averaged smallerscale
parameters. It combines a decision model, a hydraulic conductivity uncertainty model, and
groundwater flow model employed in a Monte Carlo mode. I apply the data-worth methodology to a
generic contamination scenario, where a decision maker is faced with contamination of a 2-D aquifer. The
results show that a single pumping-test measurement has higher worth than a single slug-test measurement, and that the worth of a pumping-test measurement increases with increasing distance
between the observation well and the pumping well. The worth of two slug-test measurements is
comparable with the worth of a small scale pumping-test measurement, however the large scale pumpingtest
measurement still proves to be more valuable. The higher data-worth of pumping test suggests that, on
sites with configuration similar to the generic scenario, measurements with large averaging volume
provide greater reduction in risk, and have greater impact on the decision making process.
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Hill, Todd H. "Field and laboratory measurements of the hydraulic conductivity of compacted mine waste rock." 1998. http://catalog.hathitrust.org/api/volumes/oclc/48044268.html.
Повний текст джерелаАнотація:
Thesis (M.S.)--University of Wisconsin--Madison, 1998.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 77-78).
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Lien, Bob Kuochuan. "Field measurement of soil sorptivity and hydraulic conductivity." 1989. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1989_664_sip1_w.pdf&type=application/pdf.
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Petrak, Martin J. "Development of an in situ hydraulic conductivity probe and measurement protocol." 2003. http://hdl.handle.net/1993/12328.
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21
Chen, Po-Jui, and 陳柏瑞. "Measurement of Hydraulic Conductivity Along the Vertical Direction in the Puli Basin." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/12775744051575949992.
Повний текст джерелаАнотація:
碩士臺灣大學
地質科學研究所
98
The permeability of the layer is an important parameter for groundwater research and engineering application. Although one can use pumping-test to measure average hydraulic conductivity of aquifer, one cannot obtain the permeability changes of layers. However, it is difficult to operate double packer slug test and this test is lack of accuracy. The research is measuring the permeability changes of layers on the vertical direction inside the boreholes through heat-pulse flowmeter, therefore we could obtain the data for the permeability of the aquifer changes on the vertical direction. Due to the difference of well diameters and the amount of pump water, it will cause error when measuring through flowmeter. When Reynolds number of the fluid is bigger than 2100, the flow will enter the turbulent flow status; the fluid will be not only moving forward, but also breaking into eddies and causes the measurement result larger than the reality. Measurement result is affected by the geometric shapes of flowmeter and natural convections, we have to leverage calibration formulas to adjust the measurement results. The calibration formulas would vary by different sizes of well diameters. The study has been conducted with two wells with diameter as 8 inches but different depths to reflect the water level changes of first and second aquifer. We first pumped water at the top of the well and generated a stable upward flow, and then used heat-pulse flowmeter to measure the flow speed on the vertical direction for the two wells. We recorded the permeability of the layer changes as the depth changed. By using the calibration formula, we could correct the error caused by the turbulent flow when pumping. This has been compared with the stratigraphic column and natural gama and showed great result. Leveraging pumping water data from Central Geological Survey MOEA, we could calculate its continuous changes of hydraulic conductivity on the vertical direction. The result showed that major high permeability section of first aquifer is around below 15.50 meter and the major high permeability of second aquifer is around below 40.75 meter. Although the lithology changes of aquifer is not significant, the hydraulic conductivity of high permeability sections could be as high as 4.5 times of the average hydraulic conductivity of overall aquifer.
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Tsai, Yeng-Bang, and 蔡彥邦. "comparison of hydraulic conductivity measurement by different methods in Lienhuachih forest land." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/04384072212249900319.
Повний текст джерелаАнотація:
碩士國立臺灣大學
森林環境暨資源學研究所
101
The study investigate about the saturated hydraulic properties of soil in forest watershed. This study area was at Lienhuachih watershed No. 4 and No. 5, where we choose four transects respectively selected from ridge and hillslope. Each location comprised soil depths of 0 cm and 20 cm, where Double-ring infiltrometer was used to measure field infiltration rate, and calculate the hydraulic conductivities in each point. At the same time, use the 20 cm of diameter and 40 cm of length cylinder to dig the large-scale undisturb soil samples, in order to compare the difference measurement types (Constant-Head Permeability Test and Falling-Head Permeability Test ) whether the conclusions are differ or not. Besides, collect small undisturbed soil to do physical analysis so as to compared the field and lab infiltration results and illustrate the influence of soil texture, large macroporosity, coarse porosity to the penetrate rate. By the way, we compared the difference properties in Guelph infiltrometer, tension infiltrometer and double-ring infiltrometer. The results of double ring infiltration test, the average saturated hydraulic conductivity in watershed No.5 are large than in No.4. The soil texture of No.5 is clay loam, and there is more sand; the texture of No.4 is silt clay, there is more clay. The clay water retention capacity is better than sand, so that the saturated hydraulic conductivity is watershed No.5 more large than No.4. In comparison with double ring infiltration, constant head permeability test and falling head permeability, the saturated hydraulic conductivity of double ring infiltration is all large than constant head permeability. The reason that constant head permeability’s water flow is through down to above, the soil at 30 cm is closely knit than 0~20 cm so that the saturated hydraulic conductivity is low. The saturated hydraulic conductivity of falling head permeability test is all large than double ring infiltration. The reason that falling head permeability test’s pressure head is large than double ring’s, and the falling head permeability test in good permeability soil may overestimate. Besides, we compare the hydraulic conductivity of Guelph infiltrometer, tension infiltrometer and double-ring infiltrometer. The saturated hydraulic conductivity of tension infiltrometer is lower than Guelph infiltrometer and double-ring infiltrometer, and the results of Guelph infiltrometer is closely by double-ring infiltrometer. The lab simulated rainfall conclusion, use the Brooks and Corey method to get the unsaturated hydraulic conductivity properties with water pressure head. The soil pore size distribution parameter (η) of No. 5 watershed is more large than No. 4, show that the soil porosity structure in watershed No.5 was more heterogeneous. There are more abundant soil aggressive structure and loose properties. The critical capillary head of No.4 is large than No.5, appeared that soil texture in No.4 is silt clay and micropores content is relatively high, that’s the reason why there has the smller saturated hydraulic conductivity.
23
Legowo, Eko. "Estimation of water extractability and hydraulic conductivity in tropical mollisols, ultisols, and andisols." Thesis, 1987. http://hdl.handle.net/10125/9251.
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Klenzendorf, Joshua Brandon. "Hydraulic conductivity measurement of permeable friction course (PFC) experiencing two-dimensional nonlinear flow effects." Thesis, 2010. http://hdl.handle.net/2152/ETD-UT-2010-05-977.
Повний текст джерелаАнотація:
Permeable Friction Course (PFC) is a layer of porous asphalt pavement with a thickness of up to 50 millimeters overlain on a conventional impervious hot mix asphalt or Portland cement concrete roadway surface. PFC is used for its driver safety and improved stormwater quality benefits associated with its ability to drain rainfall runoff from the roadway surface. PFC has recently been approved as a stormwater best management practice in the State of Texas. The drainage properties of PFC are typically considered to be governed primarily by two hydraulic properties: porosity and hydraulic conductivity. Both of these hydraulic properties are expected to change over the life of the PFC layer due to clogging of the pore space by trapped sediment. Therefore, proper measurement of the hydraulic properties can be problematic. Laboratory and field tests are necessary for accurately determining the hydraulic conductivity of the PFC layer in order to ensure whether the driver safety and water quality benefits will persist in the future. During testing, PFC experiences a nonlinear flow relationship which can be modeled using the Forchheimer equation. Due to the two-dimensional flow patterns created during testing, the hydraulic conductivity cannot be directly measured. Therefore, numerical modeling of the two-dimensional nonlinear flow relationship is required to convert the measureable flow characteristics into the theoretical flow characteristics in order to properly determine the isotropic hydraulic conductivity. This numerical model utilizes a new scalar quantity, defined as the hydraulic conductivity ratio, to allow for proper modeling of nonlinear flow in two-dimensional cylindrical coordinates.
PFC core specimens have been extracted from three different roadway locations around Austin, Texas for the past four years (2007 to 2010). Porosity values of the core specimens range from 12% to 23%, and the porosity data suggest a statistical decrease over time due to trapped sediment in the pore space. A series of constant head tests used in the laboratory and a falling head test used in the field are recommended for measurement of PFC hydraulic characteristics using a modified Forchheimer equation. Through numerical modeling, regressions equations are presented to estimate the hydraulic conductivity and nonlinear Forchheimer coefficient from the measureable hydraulic characteristics determined during experimental testing. Hydraulic conductivity values determined for laboratory core specimens range from 0.02 centimeters per second (cm/s) to nearly 3 cm/s. Field measurements of in-situ hydraulic conductivity vary over a range from 0.6 cm/s to 3.6 cm/s. The results of this research provide well-defined laboratory and field methods for measurement of the isotropic hydraulic conductivity of PFC experiencing two-dimensional nonlinear flow and characterized by the Forchheimer equation. This methodology utilizes a numerical model which presents a proper solution for nonlinear flow in two-dimensions.text
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Alexander, Matthew. "Evaluation of Traditional Hydrogeologic Characterization Approaches in a Highly Heterogeneous Glaciofluvial Aquifer/Aquitard System." Thesis, 2009. http://hdl.handle.net/10012/4448.
Повний текст джерелаАнотація:
The purpose of this study was to evaluate the effectiveness of traditional hydrogeologic characterization approaches in a highly heterogeneous glaciofluvial aquifer at the North Campus Research Site (NCRS), situated on the University of Waterloo campus. Continuous soil cores to a depth of approximately 18 m were collected during the installation of the CMT monitoring wells and the multi-screen pumping well. K estimates were obtained for the core by obtaining 471 samples and testing them with a falling head permeameter, as well as by utilizing empirical equations developed to estimate K. A geostatistical analysis performed on the K datasets yielded strongly heterogeneous kriged K fields for the site. K and Ss were also estimated via type curve analysis of slug and pumping test data collected at the site. The various K and Ss estimates were then evaluated by simulating the transient drawdown data using a 3D forward numerical model constructed using Hydrogeosphere (Therrien et al., 2005). Results showed that, while drawdown predictions generally improved as more complexity was introduced into the model, the ability to make accurate drawdown predictions at all of the CMT ports was inconsistent. These results suggest that new techniques may be required to accurately capture subsurface heterogeneity for improved predictions of flow in similar systems.
26
Lin, Helen, and 林海倫. "The Estimating of Hydraulic Conductivity Using 1-D Electrical Resistivity Measurement – A Case Study in the Zhuoshui River Alluvial Fan." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/5pdfpr.
Повний текст джерелаАнотація:
碩士國立交通大學
土木工程系所
101
Hydraulic conductivity (K) is an important parameter of an aquifer and is usually obtained using conventionally pumping test method. However, the pumping test method is time consuming and expensive so that only limited data can be collected. In recent years, some studies estimated hydraulic conductivity using surface electrical resistivity survey along with pumping test data. These studies demonstrate its efficiency with low requirement of pumping test data and low cost. However, majority of these studies apply simple linear regression to modeling the relationship between pumping test data (K) and formation factor derived from electric resistivity data without consideration of clay layers. Thus, the equations derived by these studies are only suitable for the study areas without clay layers. In fact, clay layers are commonly distributed in middle-fan and distal-fan. Therefore, this study divides study area, Zhuoshui River Alluvial Fan, into several zones based on the sediment distribution. Each zone has a linear regression equation derived from the pumping test data and formation factors. Moreover, this study applied these equations to develop the hydraulic conductivity distribution of the study area, which locates on the shallow aquifer of the major fan, which is bounded by the Old Zhuoshui River at the north side and by New Hu-Wei River at the south side. The result shows that the shallow aquifer of the major fan of Zhuoshui River can be divided into two zones, which are top-fan and non-top-fan areas. The regression results show good correlation between hydraulic conductivity and the formation factor in each zone. These regression equations are then used to estimate hydraulic conductivity in the study area. The results are compared between the field measurement and the results obtained from Khalil’s equations. The results indicate that the estimation error, between 11m/day and 58m/day, is much smaller than the estimation error obtained using Khalil’s equation. The results of this study can be further applied to other analyses such as groundwater modeling or water fluctuation method.
27
Judge, Aaron. "Measurement of the hydraulic conductivity of gravels using a laboratory permeameter and silty sands using field testing with observation wells." 2013. https://scholarworks.umass.edu/dissertations/AAI3589054.
Повний текст джерелаАнотація:
A new laboratory permeameter was developed for measuring the hydraulic conductivity of gravels ranging from 0.1 to 2 m/s. The release of pneumatic pressure applied to the test specimen induces an underdamped oscillatory response of the water level above the permeameter, similar to an underdamped in situ slug test response in monitoring wells. A closed form model was derived to calibrate the hydraulic minor losses in the permeameter and the hydraulic conductivity of the specimen by performing tests without and with a specimen. The majority of each test series performed on individual specimens produced hydraulic conductivity values within 10% of the average, which is very small for such a measurement. Tests were performed using the permeameter on a collection of subrounded and angular gravels prepared to measured grain size distributions and porosities. The surface area was determined by evaluating the shape and angularity using a method developed in this research and these parameters were used with the measured tortuosity and hydraulic conductivity, to back calculate the packing factor of the Kozeny-Carman equation. The results show that the packing factor for the gravels and materials tested is proportional to the tortuosity cubed. These results provide a valuable update to the Kozeny-Carman equation for predicting the hydraulic conductivity of gravels. Field slug interference tests were performed in pairs of monitoring wells installed at the same elevation in a floodplain deposit of silty sand in Dedham MA. Slug tests were performed in one of the wells while the response was monitored simultaneously in both wells. The measured responses were both analyzed by modifying the KGS model of Hyder et al. (1994) to consider the wellbore storage and filter packs effects. This modification was found to produce estimates of hydraulic conductivity based on the slugged well response that compared well with that estimated based on the observation well's response. Calibrated hydraulic conductivities for the pairs of wells tested ranged from 4x10-6 to 1.5x10-5 m/s and specific storage ranged from 2x10-5 to 7x10-4 m-1.
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Köcher, Paul. "Hydraulic traits and their relevance for water use strategies in five broad-leaved tree species of a temperate mixed forest." Doctoral thesis, 2012. http://hdl.handle.net/11858/00-1735-0000-0001-BC4A-8.
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