Download or read book Fluid Migration Through Geomembrane Seams and Through the Interface Between Geomembrane and Geosynthetic Clay Liner written by Madalena C. P. Barroso and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Composite liners are used to limit the contamination migration from landfills. Their successful performance is closely related with the geomembrane as it provides the primary barrier to diffusive and advective transport of contaminants. Critical issues on the performance of the geomembranes are the seams between geomembrane panels and the inevitable defects resulting, for instance, from inadequate installation activities. In landfills, where high density polyethylene geomembranes are usually used, seams are typically made by the thermal-hot dual wedge method. A literature review on quality control of the seams showed that, in situ, fluid-tightness of seams is evaluated in qualitative terms (pass/failure criteria), despite their importance to ensure appropriate performance of the geomembranes as barriers. In addition, a synthesis of studies on geomembrane defects indicated that defects varying in density from 0.7 to 15.3 per hectare can be found in landfills. Defects represent preferential flow paths for leachate. Various authors have developed analytical solutions and empirical equations for predicting the flow rate through composite liners due to defects in the geomembrane. The validity of these methods for composite liners comprising a geomembrane over a geosynthetic clay liner (GCL) over a compacted clay liner (CCL) has never been studied from an experimental point of view. To address the problem of fluid migration through the geomembrane seams, an attempt is made to provide a test method, herein termed as "gas permeation pouch test", for assessing the quality of the thermal-hot dual wedge seams. This test consists of pressurising the air channel formed by the double seam with a gas to a specific pressure and, then, measuring the decrease in pressure over time. From the pressure decrease, both the gas permeation coefficients, in steady state conditions, and the time constant, in unsteady state conditions, can be estimated. Experiments were carried out both in laboratory and in field conditions to study the suitability of this test to assess the quality of the seams in situ. The results obtained suggest that it is possible to assess the quality of the geomembrane seams from a non-destructive test conducted in situ by determining the time constant. To address the problem of fluid migration through geomembrane defects, composite liners comprising a geomembrane with a circular hole over a GCL over a CCL were simulated in tests at three scales. Flow rates at the interface between the geomembrane and the GCL were measured. Correspondent interface transmissivity was estimated based on final flow rates and observation of the wetted area. A parametric study was performed to evaluate the influence of the prehydration of the GCL, the hydraulic head on top of the liner and the confining stress over the liner system, on the flow rate through composite liners due to defects in the geomembrane, as well as to check the feasibility of an extrapolation of the results obtained on small-scale tests to field conditions. It was found that the transmissivity does not seem to be affected by the prehydration of the GCLs when low confining stresses were used. It also does not seem to be influenced by the increase in confining stress when non-prehydrated GCLs are used. Finally, the transmissivity does not seem to be significantly affected by the increase in hydraulic head. The results also suggest that predictions on flow rates though composite liners due to defects in the geomembrane, which are based on transmissivity values obtained in small scale tests, are conservative. Lastly, based on the transmissivities obtained in this study, empirical equations for predicting the flow rate through composite liners consisting of a geomembrane over a GCL over a CCL are proposed. Flow rates calculated using these equations are in better agreement with the flow rates measured experimentally than the empirical equations reported in literature. The new empirical equations provide design engineers with simple and accurate tools for calculating the flow rates through the above mentioned type of composite liners.

Download or read book Hard Rock Mine Reclamation written by Bruno Bussière and published by CRC Press. This book was released on 2020-12-09 with total page 499 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hard rock mines have significant effects on the territories where they operate, through both infrastructure construction as well as resource use. Due to their extractive activities, these mines store large quantities of wastes at the surface, which can be both physically and chemically unstable. Reclamation aims to return a mine site to a satisfactory state, meaning that the site should not threaten human health or security, should not generate in the long term any contaminant that could significantly affect the surrounding environment, and should be aesthetically acceptable to communities. This book focuses on the reclamation of waste storage areas, which constitute the main source of pollution during and after mine operations, and especially issues with acid mine drainage and neutral contaminated drainage. Features: Provides fundamental information and describes practical methods to reclaim mine-waste facilities Compares the different methods and illustrates their application at sites through case studies Identifies new reclamation issues and proposes solutions to address them Presents existing and new technologies to reclaim mine waste disposal areas from hard rock mines in different climatic conditions Integrates reclamation into mine operations and long term performance of techniques used through an interdisciplinary approach With mine site reclamation a young and still emerging science, the training needs for professionals and students working in this field are huge. This book is written from an engineering point of view and in it the authors identify new reclamation issues and propose well-tested as well as innovative approaches to addressing them. Students in graduate programs focused on mines and the environment as well as professionals already working in departments related to mine site reclamation will find this book to be a valuable and essential resource.

Download or read book Geomembranes Identification and Performance Testing written by J.M. Rigo and published by CRC Press. This book was released on 1990-12-06 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geomembranes are increasingly being used in transportation, environmental and geotechnical applications to control gas and liquid movement. This book provides authoritative guidance on testing of geomembranes. It has been prepared by an international committee of experts under the auspices of RILEM, the International Union of Research and Testing L

Download or read book Static and Dynamic Shear Strength of a Geomembrane geosynthetic Clay Liner Interface written by Jason D. Ross and published by . This book was released on 2009 with total page 241 pages. Available in PDF, EPUB and Kindle. Book excerpt: The series of shear tests were performed to investigate a number of factors: (1) whether internal GCL failure could be induced at high normal stresses, (2) the effect that a range of normal stresses (13 to 1382 kPa) can have on interface behavior, and (3) the effects of displacement rate and displacement amplitude on static and dynamic shear response, respectively.

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 Laboratory Study of Geosynthetic Clay Liner Shrinkage when Subjected to Wet dry Cycles written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Geosynthetic Clay Liners (or GCLs) are often used in conjunction with a geomembrane for landfills and heap-leach pads, where their function is to minimize leakage that may occur through holes in the geomembrane. GCLs are installed with overlapping panels and powdered bentonite placed between the overlaps to provide a better seal. Recent field exhumations of GCLs installed beneath a geomembrane left exposed to solar radiation have shown panel shrinkage; in some cases, this shrinkage was enough to leave exposed areas unprotected by the GCL. One hypothesized cause of this shrinkage is cyclic wetting and drying of the GCL. To investigate the hypothesis that wet/dry cycles have the potential to cause irrevocable shrinkage of GCL panels, a total of 8 different products were tested under idealised conditions in the laboratory. Shrinkage was measured using both hand measurements and digital image correlation techniques. A number of variables were tested for their effects on panel shrinkage, including mass per unit area, size and aspect ratio, restraint, moisture content and wetting conditions, and GCL type. Wet/dry cycles were found to cause sufficient shrinkage to explain the shrinkage observed in all but one field case. The shrinkage of any particular product was found to be variable. In particular the shrinkage was found to be sensitive to the distribution of the mass of bentonite within a specimen with the highest shrinkage being observed when there was the greatest variability in mass distribution. It is shown that some GCL products are more prone to shrinkage than others. Consideration is also given to the potential effectiveness of heat-tacking of GCL seams to reduce panel shrinkage in the field. Specimens of GCL which had been heat-tacked in the field were tested under similar cyclic conditions as used in the abovementioned laboratory tests, and the shrinkage response noted. The results indicate that such a technique has promise as a method of inhibiting shrinkage o.

Download or read book Hydraulic and Chemical Properties of Geosynthetic Clay Liners Overlain by Geomembrane in Landfill Final Covers written by Joseph Scalia and published by . This book was released on 2009 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dynamic Shear Behavior of a Needle punched Geosynthetic Clay Liner Geomembrane Interface at a High Normal Stress written by Alexander Nicholas Stern and published by . This book was released on 2009 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt: Commonly used geosynthetic materials were carefully chosen from some of the most well-known manufacturers. The GCL was Bentomat DN provided by CETCO (Hoffman Estates, IL). The GMX was a HDPE Microspike/Smooth product produced by Agru America (Georgetown, SC).

Download or read book Geosynthetics Leading the Way to a Resilient Planet written by Giovanni Biondi and published by CRC Press. This book was released on 2023-09-15 with total page 2826 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the proceedings of the 12th International Conference on Geosynthetics (12 ICG), held in Roma, Italy, 17-21 September 2023. About 750 Authors - Academics, Researchers, Students, Practitioners, Contractors and Manufacturers – contributed to the peer-reviewed papers of this volume, which includes the Giroud lecture, the Bathurst lecture, the Rowe lecture, four keynote lectures and 296 technical papers. The content of these proceedings illustrates the sustainable use of geosynthetics in a variety of innovative as well as consolidated applications. After the sustainability implications in the correct use of geosynthetics, the ability to overcome the natural events effects, often related to the climate change, and to adequately afford the human activities (as the increase of pollution) forced to refer to a new keyword: Resiliency. The 12 ICG intends to become the base for the next step, hence the conference theme is 'Geosynthetics, Leading the Way to a Resilient Planet'. The conference topics, through general and parallel sessions, invited presentations and keynote lectures, address the most recent developments in geosynthetic engineering, and stimulate fruitful technical and scientific interaction among academicians, professionals, manufacturers, students. The 12 ICG proceedings contain a wealth of information that could be useful for researchers, practitioners and all those working in the broad, innovative and dynamic field of geosynthetics.

Download or read book Proceedings of the Fifth International Conference on Geotextiles Geomembranes and Related Products Singapore 5 9 September 1994 written by G. P. Karunaratne and published by . This book was released on 1994 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Damage to HDPE Geomembrane from Interface Shear Over Gravelly Compacted Clay Liner written by Stuart Thielmann and published by . This book was released on 2012 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: Liner systems are used in a wide array of applications to prevent the spread of contaminants into the environment. These liner systems have two main components: a geomembrane (GM) and a compacted clay liner (CCL). GMs are susceptible to damage both during installation and the service life of the liner system. The most common source of damage is puncture due to granular material (e.g., gravel or stones) in direct contact with the GM resulting in the formation of a hole in the liner. While multiple studies have investigated puncture due to a granular layer above the GM, puncture due to granular material in the subgrade below has not received comparable attention. A series of tests were performed using a large-scale direct shear machine to investigate possible damage to a high density polyethylene (HDPE) GM due to interface shearing over a gravelly CCL for a wide range of normal stress levels. Results indicate that shear displacement of a HDPE GM over a gravelly CCL can significantly increase GM damage compared to static pressure alone. Damage increased with increasing normal stress. Essentially no damage was observed at the lowest normal stress (72 kPa), while severe damage was observed at high normal stress (1658 kPa). Placement of a hydrated nonwoven/nonwoven (NW/NW) needle-punched (NP) geosynthetic clay liner (GCL) between a GM and gravelly CCL was shown to dramatically reduce GM damage, including one test conducted at very high normal stress (4145 kPa).

Download or read book Engineered Contaminated Soils and Interaction of Soil Geomembranes written by Jay N. Meegoda and published by American Society of Civil Engineers. This book was released on 1996 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to liability issues, landfills are no longer considered the best method of waste disposal. Innovative, safe disposal methods for large quantities of contaminated soils and waste are sought by engineers. In urban or industrial areas with most of the contamination, it has become very attractive to engineer contaminated soils and waste by physical or chemical methods and reuse them as construction materials. This proceedings addresses the following: the creation of useful products from contaminated soils and waste; changes in soil or waste properties after processing; logistics of the operations; and the regulatory issues associated with such usage. While alternative methods of disposal are being utilized, civil engineers are still involved in the development of large containment systems and must continue to increase their knowledge of these systems. Solid-waste landfills are made of multi-layered soil and geosynthetic liner systems underlying the fills and providing surface coverage. to a large degree by the shear strengths developed at interfaces between the soils and the geosynthetics forming part of either the liner or the cover systems. In this proceedings, recent research efforts to measure the interface strength between geomembranes and soils are presented.

Download or read book Interface Transmissivity Measurement in Multicomponent Geosynthetic Clay Liners written by K. P. von Maubeuge and published by . This book was released on 2013 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Three different multicomponent geosynthetic clay liners (GCLs) from different manufacturers are tested in a transmissivity cell with a new testing procedure to quantify the flow rate and the interface transmissivity between the coating or attached film presenting a hole and the upper geotextile of the GCL. The testing device was previously used in studies aiming to evaluate the interface transmissivity between a damaged geomembrane (GM) and a regular GCL. Different results are obtained regarding the evolution with the time of the flow rate ranging from 1.73 x 10-11 m3/s to 2.18 x 10-10 m3/s at steady state, which is on average in the range of flow rate results obtained with a GM-GCL composite liner. Additional tests performed by adding a GM on top give lower values of flow rates. This shows the importance of the film or coating rigidity for decreasing flow rate and insuring a better quality contact at the interface.

Download or read book Internal and Interface Shear Strength of Geosynthetic Clay Liners written by John Scott McCartney and published by . This book was released on 2002 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book G otechnique written by and published by . This book was released on 2005 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Designing with Geosynthetics written by Robert M. Koerner and published by . This book was released on 1990 with total page 680 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geosynthetic materials have entered the mainstream in the professional arena and are no longer considered new construction material. Professionals need to keep up with the nuances of how geosynthetics work. Emphasizes design by function; overviews all types of geosynthetics, with stand-alone units on particular materials. Uses S.I. units for all problems and examples. Expands coverage of containers and tubes in the geotextile chapter. Discusses walls and slope design, including seismic analysis, in the geogrid chapter. Treats wet landfills, agricultural waste, waste stability, and dam waterproofing in the geomembrane chapter. Discusses new products and related performances in the geosynthetic clay liner chapter. Discusses new products and related behavior, including fiber reinforcement and wall drainage, in the geocomposite chapter. Adds a completely new chapter on geofoam. A useful reference for transportation, geotechnical, environmental, and hydraulics professionals and engineers.

Download or read book Canadian Geotechnical Journal written by and published by . This book was released on 2012 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: