Download or read book How to Improve the Quality of Laboratory Permeability Tests in Rigid Wall Permeameters A Review written by Robert P. Chapuis and published by . This book was released on 2020 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: ASTM D2434, Standard Test Method for Permeability of Granular Soils (Constant Head) (Withdrawn 2015) , and ASTM D5856, Standard Test Method for Measurement of Hydraulic Conductivity of Porous Material Using a Rigid-Wall, Compaction-Mold Permeameter , are used to measure the saturated hydraulic conductivity, K sat , of soil specimens in rigid-wall permeameters (RWPs). Several laboratory conditions and settings explain why the tests do not give K sat values but unsaturated hydraulic conductivity, K ( S r ), values for a degree of saturation, S r , that is often in the 80-85 % range. It is suggested to improve ASTM D2434 and ASTM D5856 by adding two requirements: (1) use a watertight-and-airtight RWP (a control method is provided), and (2) use a mass-and-volume method to obtain the true S r value of the tested specimen. To illustrate potential detrimental impacts of current standards, the article describes a case where sand was planned to be used as a filter layer for a solid waste project. Large quantities of sand had been delivered at the construction site. The K sat value of the sand, as compacted, had to exceed 10 -4 m/s to satisfy a bylaw. To prove this, two laboratories followed ASTM D2434 for their tests but found K values of 5-8×10 -5 m/s. The project engineers asked the authors to make verifications. The prior tests were redone and yielded similar K values. However, it was found that the real S r value was close to 80 % instead of being assumed to be 100 %. Other tests were performed after using vacuum and deaired water in a watertight-and-airtight permeameter: the specimens reached S r =100 % and gave K sat values of about 2×10 -4 m/s, 3-4 times higher than initial tests. As a result, the already delivered sand satisfied the bylaw condition and there was no need to return large quantities of sand already delivered, to purchase a new type of sand after having done laboratory tests, and to have a time delay in construction, all these items having a high economic impact.
Download or read book Permeability Tests in Rigid Wall Permeameters written by RP. Chapuis and published by . This book was released on 2004 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper documents a method to determine the degree of saturation, Sr, of a soil specimen at any time during a rigid-wall permeameter test. This method first indicates that the tested specimen usually is not fully saturated. Then it is used to prove that the usual test termination criterion based on equality of inflow and outflow volumes may be misleading. Examples are provided where the two volumes were equal within 1 %, whereas Sr increased from 80 to 100 % and k increased by a factor of 4. Without knowing the technique to determine the Sr value at any time, the test would have been stopped prematurely and would have given some k(Sr) value for an unknown Sr with the risk of misinterpreting this result as k(Sr = 100 %). New equations for gas transfer between water and gas bubbles are also established and experimentally verified for specimens permeated with either deaired water or water over-saturated with air.
Download or read book Large Scale Laboratory Permeability Testing of a Compacted Clay Soil written by CD. Shackelford and published by . This book was released on 1991 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Constant-head permeability (hydraulic conductivity) tests were performed on samples of a compacted clay soil using a 0.914 by 0.914 by 0.457-m (3 by 3 by 1.5-ft) large-scale, double-ring, rigid-wall permeameter. A naturally occurring silty clay soil was used for the permeability tests. The soil was separated into five different fractions representing five different ranges in precompaction clod sizes. Soil from each of the soil fractions was used for soil specimens. The soil for the large-scale permeameter was compacted in two 7.62-cm (3-in) lifts. Small-scale, constant-head permeability tests also were performed on soil specimens compacted into standard Proctor molds (9.44 × 10-4 m3). Comparison of the results from the two different scales of permeameters indicated that, in all cases, the permeability for a given soil fraction was higher in the large-scale permeameter than it was in the small-scale permeameter. In addition, the permeability for all soil fractions measured in the large-scale permeameter ranged from 0.6 to 2.4 orders of magnitude higher than the value measured in the small-scale permeameter. As a result of the permeability tests performed in this study, there appears to be a scale effect associated with laboratory permeability testing, especially when a significant proportion of the soil being tested consists of precompaction clod sizes which are large relative to the size of the permeameter. The scale effect in this study is thought to be due to the relationship between the compactive effort and the different degrees of confinement associated with the different scales of permeameters. The implication of the study is that a more realistic evaluation of the fieldmeasured permeability of a compacted clay soil may be possible in the laboratory if the permeameter is sufficiently large to test a representative sample of soil.
Download or read book Canadian Geotechnical Journal written by and published by . This book was released on 1989-02 with total page 842 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Permeability Testing with Flexible Wall Permeameters written by DE. Daniel and published by . This book was released on 1984 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The equipment and testing procedures used at The University of Texas at Austin for measuring the hydraulic conductivity of fine-grained soil with flexible-wall permeameters are described. The permeability cell is similar to a triaxial cell; it has interchangeable base pedestals to accomodate specimens of various diameters, is equipped with double drainage lines to the top and bottom of the test specimen, and can accomodate a differentially acting pressure transducer to measure head loss across the soil specimen. An air-over-liquid interface is maintained in devices called "accumulators." Stainless steel accumulators designed with transparent sight tubes offer excellent resistance to corrosion, are convenient to use, and can be used with a wide range in flow rates. The permeability tests are normally performed using back pressure. Care is taken to be certain that flow is steady state and that the soil is permeated long enough for the influent liquid to pass through the soil and to appear in the effluent liquid in full concentration. When clays are permeated with dilute chemicals that are adsorbed by the soil, testing times on the order of months or years may be required to achieve full breakthrough of the permeant liquid. Use of large hydraulic gradient and excessive effective confining pressure are sometimes difficult to avoid but are two of the most important sources of potential error.
Download or read book Fixed Wall Versus Flexible Wall Permeameters written by DC. Anderson and published by . This book was released on 1985 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Permeameters are of two general types: fixed-wall and flexible-wall cells. A controversy has developed over which type of cell is best suited for measuring the hydraulic conductivity of relatively impermeable, fine-grained soils. The various types of permeameters are discussed and their relative advantages and disadvantages are listed. Differences in applied stress, boundary leakages, and degree of saturation are the major differences between cells. It is concluded that no one type of cell is best suited to all applications. Data show that the type of permeameter used has little effect for laboratory-compacted clay permeated with water but can have a major effect for clays permeated with concentrated organic chemicals. Fixed-wall cells are perhaps best suited to testing laboratory-compacted clays that will be subjected to little or no effective overburden pressure in the field. Flexible-wall cells are better suited to testing undisturbed samples of soil (to minimize boundary leakages) and testing soils that will be subjected to significant effective stress.
Download or read book Evaluation of HMA Laboratory Permeability Using the Karol Warner Flexible Wall Permeameter written by Thomas D. Justis and published by . This book was released on 2001 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Issues in Global Environment Biology and Geoscience 2013 Edition written by and published by ScholarlyEditions. This book was released on 2013-05-01 with total page 1126 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Global Environment—Biology and Geoscience: 2013 Edition is a ScholarlyEditions™ book that delivers timely, authoritative, and comprehensive information about Wildlife Research. The editors have built Issues in Global Environment—Biology and Geoscience: 2013 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Wildlife Research in this book to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Global Environment—Biology and Geoscience: 2013 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Design Construction and Evaluation of Clay Liners for Waste Management Facilities written by L. J. Goldman and published by . This book was released on 1988 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1989 with total page 878 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessment of the Performance of Engineered Waste Containment Barriers written by National Research Council and published by National Academies Press. This book was released on 2007-09-22 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: President Carter's 1980 declaration of a state of emergency at Love Canal, New York, recognized that residents' health had been affected by nearby chemical waste sites. The Resource Conservation and Recovery Act, enacted in 1976, ushered in a new era of waste management disposal designed to protect the public from harm. It required that modern waste containment systems use "engineered" barriers designed to isolate hazardous and toxic wastes and prevent them from seeping into the environment. These containment systems are now employed at thousands of waste sites around the United States, and their effectiveness must be continually monitored. Assessment of the Performance of Engineered Waste Containment Barriers assesses the performance of waste containment barriers to date. Existing data suggest that waste containment systems with liners and covers, when constructed and maintained in accordance with current regulations, are performing well thus far. However, they have not been in existence long enough to assess long-term (postclosure) performance, which may extend for hundreds of years. The book makes recommendations on how to improve future assessments and increase confidence in predictions of barrier system performance which will be of interest to policy makers, environmental interest groups, industrial waste producers, and industrial waste management industry.
Download or read book Pervious Concrete Pavements written by Paul D. Tennis and published by . This book was released on 2004 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Powder Surface Area and Porosity written by S. Lowell and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rapid growth of interest in powders and their surface properties in many diverse industries prompted the writing of this book for those who have the need to make meaningful measurements without the benefit of years of experience. It is intended as an introduction to some of the elementary theory and experimental methods used to study the surface area, porosity and density of powders. It may be found useful by those with little or no training in solid surfaces who have the need to quickly learn the rudiments of surface area, density and pore-size measurements. Syosset, New York S. Lowell May, 1983 J. E. Shields Xl List of symbols Use of symbols for purposes other than those indicated in the following list are so defined in the text. Some symbols not shown in this list are defined in the text. d adsorbate cross-sectional area A area; condensation coefficient; collision frequency C BET constant c concentration D diameter; coefficient of thermal diffusion E adsorption potential f permeability aspect factor F flow rate; force; feed rate 9 gravitational constant G Gibbs free energy GS free surface energy h heat of immersion per unit area; height H enthalpy Hi heat of immersion Hsv heat of adsorption BET intercept; filament current k thermal conductivity; specific reaction rate K Harkins-Jura constant I length L heat of liquefaction M mass M molecular weight n number of moles N number of molecules; number of particles N Avagadro's number .
Download or read book Evaluation of Soil and Rock Properties written by P. J. Sabatini and published by . This book was released on 2004-10-01 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document presents state-of-the-practice information on the evaluation of soil and rock properties for geotechnical design applications. This document addresses the entire range of materials potentially encountered in highway engineering practice, from soft clay to intact rock and variations of materials that fall between these two extremes. Information is presented on parameters measured, evaluation of data quality, and interpretation of properties for conventional soil and rock laboratory testing, as well as in situ devices such as field vane testing, cone penetration testing, dilatometer, pressuremeter, and borehole jack. This document provides the design engineer with information that can be used to develop a rationale for accepting or rejecting data and for resolving inconsistencies between data provided by different laboratories and field tests. This document also includes information on: (1) the use of Geographical Information Systems (GIS) and Personal Data Assistance devices for the collection and interpretation of subsurface information; (2) quantitative measures for evaluating disturbance of laboratory soil samples; and (3) the use of measurements from geophysical testing techniques to obtain information on the modulus of soil. Also included are chapters on evaluating properties of special soil materials (e.g., loess, cemented sands, peats and organic soils, etc.) and the use of statistical information in evaluating anomalous data and obtaining design values for soil and rock properties. An appendix of three detailed soil and rock property selection examples is provided which illustrate the application of the methods described in the document.
Download or read book Time Lag and Soil Permeability in Ground water Observations written by Mikael Juul Hvorslev and published by . This book was released on 1951 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soil Physics Measurements written by Christiaan Dirksen and published by Catena. This book was released on 1999 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1989 with total page 1368 pages. Available in PDF, EPUB and Kindle. Book excerpt:
