Download or read book A Comparison of Field and Laboratory Methods for the Determination of Hydraulic Conductivity of the Cohansey Sand Formation in Gloucester County New Jersey written by Martin Patrick Derby and published by . This book was released on 1992 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Comparison of Laboratory and Field Methods for the Estimation of Hydraulic Conductivity in a Sand and Gravel Aquifer written by Linda Peiperl Warren and published by . This book was released on 1992 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Comparison of Field and Laboratory Conductivity Measurements on Plainfield Sand written by David Bernard Lesczynski and published by . This book was released on 1969 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Comparison of Field and Laboratory Measurements of Hydraulic Conductivity written by A. Guerra and published by . This book was released on 1992 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: The hydraulic conductivity of a soil was measured in the laboratory and in the field. Although each technique used yielded consistent results, the hydraulic conductivity obtained differed over several orders of magnitude. These differences in hydraulic conductivity can only be attributed to macroscopic features that weigh differently depending on the mass of soil affected by the different tests.
Download or read book Techniques to Determine Spatial Variations in Hydraulic Conductivity of Sand and Gravel written by Kathryn M. Hess and published by . This book was released on 1991 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Variability and Estimation of Hydraulic Conductivity in C Horizons of Sandy Loam Glacial Till Soils Comparison of One step Outflow Laboratory Method to an I n S i t u Method for Measuring Hydraulic Conductivity written by Dan B. Jaynes and published by . This book was released on 1978 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparison of Four Laboratory and Field Methods for Determining Saturated Hydraulic Conductivity in the Unsaturated Zone written by Dana Candice Rogerson and published by . This book was released on 1995 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Determination of Hydraulic Conductivity from Grain Size Analysis written by Michael Kasenow and published by Water Resources Publication. This book was released on 2002 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparison Between Various Field and Laboratory Measurements of the Hydraulic Conductivity of Three Clay Liners written by G. Didier and published by . This book was released on 2002 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: For waste facilities, field assessment of the hydraulic conductivity of fine- grained soils has been a real challenge for the past decades that has led to several types of test methods. Although standards (ASTM, NF, etc.) have been adopted in many countries, any test method needs careful application for constructing quality-control programs. The type of apparatus, its geometry, and even specimen preparation may be major sources of discrepancy. We compared hydraulic-conductivity values obtained from various field-testing methods (open, sealed, single and double infiltrometers, and borehole methods), and laboratory-testing methods such as oedometer cells or rigid and flexible-wall permeameters. Three materials were tested in this study: a compacted sandbentonite mixture, compacted clayey silt, and natural sandy clay. The field tests were run on soil-test pads whose characteristics were defined beforehand in the laboratory and the field. Comparison of the results shows a large range of hydraulic-conductivity values for a single soil sample. Such variability can commonly be explained by a scale effect, as demonstrated by the use of various types of diameter or geometry for the field or laboratory tests. Soil behavior (swelling or shrinkage) and test-analysis methods (saturated or unsaturated-flow analysis) are other important parameters. In conclusion, we identified the main problems affecting tests with infiltrometers and permeameters, and how they can be reduced or avoided by the improvement of current techniques.
Download or read book A Comparison of Three Field Methods for Measuring Saturated Hydraulic Conductivity written by Jay Dunton Dorsey and published by . This book was released on 1989 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Comparison Between Field and Laboratory Measurements of Hydraulic Conductivity in a Varved Clay written by DJ. DeGroot and published by . This book was released on 1994 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: The measurement of hydraulic conductivity using a variety of field and laboratory techniques was evaluated at a site consisting of medium stiff and soft lacustrine varved clay in western Massachusetts. Field measurements were obtained by conducting "slug" tests in both predrilled and push-in piezometers and also from pore pressure dissipation tests using the piezocone and flat dilatometer. Laboratory hydraulic conductivity values were obtained for both vertical and horizontal flow conditions using a flexible wall permeameter and by indirect estimation from 1-dimensional consolidation tests. Based on a comparison of tests conducted throughout the profile, laboratory flexible wall tests with vertical flow gave the lowest values of hydraulic conductivity whereas the predrilled piezometers yielded the highest values. Of all the field techniques, the push-in piezometers gave the lowest values. Hydraulic conductivity values interpreted from piezocone and flat dilatometer dissipation tests tended to be between those obtained from the predrilled and push-in piezometers. Results from tests in predrilled piezometers show that the hydraulic conductivity increases with increasing screen length, showing the influence of scale effects. The results of this study clearly show that estimation of hydraulic conductivity for this soil is highly dependent on scale effects, the test technique used and on the direction of flow (i.e., parallel versus perpendicular to the orientation of the varves).
Download or read book Comparison of Field Methods for Measuring Hydraulic Conductivity written by Abdul Jamil and published by . This book was released on 1971 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparison of Field Methods for Measuring Hydraulic Conductivity of Soil written by L. S. Ying and published by . This book was released on 1977 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparison of Laboratory and Field Methods for Determining the Quasi Saturated Hydraulic Conductivity of Soils written by and published by . This book was released on 1997 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laboratory and field ponded infiltration tests in quasi-saturated soils (containing entrapped air) exhibit the same three-stage temporal variability for the flow rate and hydraulic conductivity. However, the values for the hydraulic conductivity may differ by as much as two orders of magnitude due to differences in the geometry and physics of flow when different laboratory and field methods are applied. The purpose of this paper is to investigate this variability using a comparison of results of ponded infiltration tests conducted under laboratory conditions using confined cores, with results of field tests conducted using partially isolated cores and double-ring infiltrometers. Under laboratory conditions in confined cores, during the firs stage, the water flux decreases over time because entrapped air plugs the largest pores in the soils; during the second stage, the quasi-saturated hydraulic conductivity increases by one to two orders of magnitude, essentially reaching the saturated hydraulic conductivity, when entrapped air is discharged from the soils; during the third stage, the hydraulic conductivity decreases to minimum values due to sealing of the soil surface and the effect of biofilms sealing the pores within the wetted zone. Under field conditions, the second stage is only partially developed, and when the surface sealing process begins, the hydraulic pressure drops below the air entry value, thereby causing atmospheric air to enter the soils. As a result, the soils become unsaturated with a low hydraulic conductivity, and the infiltration rate consequently decreases. Contrary to the laboratory experiments in confined cores, the saturated hydraulic conductivity cannot be reached under field conditions. In computations of infiltration one has to take into account the variations in the quasi-saturated and unsaturated hydraulic conductivities, moisture and entrapped air content, and the hydraulic gradient in the quasi-saturated or unsaturated soils.
Download or read book Hydraulic Conductivity Determinations by Several Field Methods in a Sand Tank written by D.E. Smiles and published by . This book was released on 1965 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparison of Different Methods to Measure Hydraulic Conductivity K in Florida Sand Soils at the Ground Water Interface written by Sala Yamwong and published by . This book was released on 1996 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparison of Different Methods of Measuring Soil Hydraulic Conductivity written by Luciano Behnke Duhart and published by . This book was released on 1958 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
