A Flexible Membrane Liner Comparison Author:   M. Sadlier and R. Frobel   A tabular comparison of liner attributes from the paper "Geomembrane Properties - A Comparitive Perspective" presented at the GeoEnvironmental Conference, Melbourne, November 1997.   Publication: GeoEnvironmental Conference 1997    Click here for the document   GSA Tech Doc ID #:301

CONTACT INFO: Geosynthetic Consultants Australia Mike Sadlier 120 Male St Brighton, VIC 3186 Australia Phone: 61 3 9503 0393 or cell 61 412 887 000 Fax: 61 3 9417 3727 Email: sadlier@attglobal.net

A Fundamental Approach for an Investigation of Behavior Characteristics of the Vegetation Structures Using Seeded Sandbags Author:   Kim, Yoo, Park, J. Lee and C. Lee   ABSTRACT: In this study, a novel green retaining wall technology, named as GRW (Green Retaining Wall), was developed to enhance constructability, cost-effective and geoenvironment friendly system. Up to now, the GRW system has been investigated mainly focusing on an establishment of the design procedure. The analytical procedure for sand bag design has been proposed to evaluate frictional characteristics and stability of the GRW system. In addition, large-scale direct shear tests were performed to establish the frictional characteristics between the seeded sandbag and the connection unit of the GRW system. A stability analysis formula was proposed for the GRW system that can be applied to riverside or shoreline. Hydraulic experiments were performed to quantify the loss rate of sand from the sand bags. By conducting the safety analysis for the flow pressure proposed in this study, the maximum allowable velocity and the minimum required weight were calculated and compared with those of the conventional design cases. The insights into the behavior of the GRW system observed in this study will be reported and discussed.   Publication: 3rd Asian Regional Conf on Geosynthetics    Click here for the document   GSA Tech Doc ID #:278

CONTACT INFO: IGS Korea Chungsik Yoo Sungkyunkwan University 300 Chun-chun Dong, Jang-An Gu Swuon, Kyong-Gi Do 440-746 Korea Phone: 82 331 290 7518 Fax: 82 331 290 7549 Email: csyoo@skku.edu Website: http://www.geosyntheticssociety.org/chapters.htm#korean

A Geocomposite Barrier for Hydrocarbon Containment in the Arctic Author:   Bathurst, Rowe, Zeeb, and Reimer   The paper describes the background and remediation steps that were taken to contain migration of a subsurface hydrocarbon contaminant plume at a site in the Canadian Arctic. A composite liner consisting of a novel fluorine surface-treated high-density polyethylene geomembrane and a geosynthetic clay liner was selected as the short-term (several years) barrier solution. The paper describes the design details, the selection criteria, and the challenges that were overcome to install the barrier system. A complimentary program of site monitoring is underway together with a parallel program of laboratory testing investigating the long-term effects of freeze-thaw, low temperatures, and contact with jet fuel on specimens of the barrier components. Results from site monitoring show that the barrier system is performing as planned three years after installation. Laboratory tests completed to date show that the geosynthetic barrier materials can be expected to maintain acceptably low rates of hydrocarbon diffusion and advection well beyond the original 3-year design life of the barrier system.     Click here for the document   GSA Tech Doc ID #:496

CONTACT INFO: International Journal of Geoengineering Case Histories Elxis s.a. Greece Email: journal@geoengineer.org Website: http://casehistories.geoengineer.org

A Guide to Fibers for Nonwovens Author:   NonWovens Industry Staff   This report describes Reclamation's recent experience with various geomembranes, and is divided into 2 sections: Field Studies and Laboratory Studies. The Field Study portion will discuss results of physical property testing of field samples of buried and exposed geomembranes. The Laboratory Study portion will provide results from out-of-plane laboratory testing of six different geomembrane polymers using two different performance test methods.     Click here for the document   GSA Tech Doc ID #:44

CONTACT INFO: Nonwovens Industry Kathleen Scully 70 Hilltop Road, Third Floor Ramsey, New Jersey 07446 USA Phone: +1-201-825-2552 ext 334 Fax: +1-201-825-0553 Email: kathleen@rodpub.com Website: http://www.nonwovens-industry.com

A Look Back at Geosynthetic Testing and Specification Standardization - A Celebration of 20 Years for ASTM International Committee D35 on Geosynthetics Author:   L. David Suits   The formal process of standardizing testing protocols and specifications for geosynthetics had its beginning in the fall of 1977. A group of individuals gathered in New York City in response to a questionnaire sent out to determine such interest in what were then known as “construction fabrics,” or “filter fabrics.” There have been many persons involved in the progress that has been made since that initial meeting. Many still are, but many have moved onto other responsibilities within their organizations, left the field entirely, or retired. This paper will trace the activities and progress of the standardization since that time. Some of the early names involved will be highlighted also, as they are responsible for where we are today.   Publication: Koerner Symposium 2004    Click here for the document   GSA Tech Doc ID #:337

CONTACT INFO: GSI George Koerner 475 Kedron Avenue Folsom, PA 19033 USA Phone: 610-522-8440 Fax: 610-522-8441 Email: gkoerner@dca.net Website: http://www.geosynthetic-institute.org

A Methodology for Cylinder Testing of Protectors for Geomembranes Author:   US Environmental Protection Agency EPA   A performance test to determine the protection afforded to a geomembrane by a geotextile or other protective material, in specific site conditions.     GSA Tech Doc ID #:16

CONTACT INFO: US Environmental Protection Agency Kenneth Shuster Office of Solid Waste 401 M. Street, S.W. Washington, DC 20460 United States of America Phone: (202) 260-2214

A Model Demonstration of Geomembrane Puncture Protection Author:   Ian Peggs   A Model Demonstration of Geomembrane Puncture Protection - Narejo et al (1996) have proposed that the mass/unit area determines the cushioning efficiency of a nonwoven geotextile, while Jones et al (2000) propose CBR is the most appropriate parameter to use. The simple demonstration that follows shows that mass is relevant in geotextiles of a given type and structure, but that structural differences have a more significant effect on fundamental cushioning efficiency. In fact, lighter materials with a more rigid structure may produce more cushioning than heavier materials of a "looser" structure. Consider the fibers of a geotextile to be equivalent to a pile of loose scaffolding rods - the ability of a drainage stone to penetrate the loose rods is simply a function of their mass. Now take the same rods over the same area and assemble them into a rigid framework structure - this rigid structure (of the same mass) will provide far more protection against the penetrating stone.   Publication: I-CORP INTERNATIONAL    Click here for the document   GSA Tech Doc ID #:66

CONTACT INFO: I-CORP INTERNATIONAL Inc. ( ICORP ) Ian Peggs 6072 N. Ocean Blvd. Ocean Ridge, FL 33435 USA Phone: + 1 561-369-0795 Fax: + 1 561-369-0895 Email: icorp@geosynthetic.com Website: http://www.geosynthetic.com

A Study on Consolidation Behavior of Dredged Clay with Horizontal Drains Author:   Jang, J. Y. Park, C. S. Park, Kim   ABSTRACT: A numerical analysis method was developed to predict the consolidation behavior of very soft soil with horizontal drains under the action of the gravity pressure. Especially, seepage pressure produced at installed horizontal drains was considered in the analysis by developing a new boundary condition for drains in arbitrary arrangement. The numerical analysis for soil with horizontal drains was compared with the case of self-weight consolidation. The influence of design factors, such as a lateral spacing and a depth of installation of drains, on consolidation process was studied. As a result of analysis, it is found that the time to reach the degree of consolidation of 95% using horizontal drains takes 9 times less than that of self-weight consolidation and the whole settlement of clay with drains was occurred more than three times compared with the case without drains.   Publication: 3rd Asian Regional Conf on Geosynthetics    Click here for the document   GSA Tech Doc ID #:288

CONTACT INFO: IGS Korea Chungsik Yoo Sungkyunkwan University 300 Chun-chun Dong, Jang-An Gu Swuon, Kyong-Gi Do 440-746 Korea Phone: 82 331 290 7518 Fax: 82 331 290 7549 Email: csyoo@skku.edu Website: http://www.geosyntheticssociety.org/chapters.htm#korean

A Study on Reliability Analysis for Reinforced Earth Retaining Walls Author:   Chun, Kim, Min   ABSTRACT: Traditionally, the reliability of retaining walls is achieved through the use of safety factors or margins and adopting conservative assumption in the process of design, that is, by ascertaining that a minimum supply condition will remain adequate under a maximum demand condition. However that is often defined on the basis of subjective judgments. Such a traditional design methods are difficult to quantify and lack the logical basis of describing uncertainty. Especially, reinforced walls consider not only soil properties but soil-reinforcement interaction uncertainties. There has been much emphasis recently the use of probabilistic method in the geotechnical engineering. The most effective applications of probabilistic methods are involving relative probabilities of failure or illuminating the effects of uncertainties in the parameter. This thesis described how probabilistic description of soil parameters and soil-reinforcement interaction parameters were applied to the stability analysis. The first-order, second moment approach was explored and applied to the design of reinforced retaining walls. An example illustrated the relative contribution of uncertainties about different parameters to the reliability of the reinforced retaining walls. The results obtained from this study were follows; the reliability of the soil-reinforcement interface friction angle, d was highly sensitive to the coefficient of variation. However, when the reinforced fill unit weight ?r, and the reinforcement length, L were lower than the limited values, the probabilities of failure were increased. The reliability of the retained backfill soil unit weight, ?f in the unreinforced area was lowly sensitive to the coefficient of variation.   Publication: 3rd Asian Regional Conf on Geosynthetics    Click here for the document   GSA Tech Doc ID #:281

CONTACT INFO: IGS Korea Chungsik Yoo Sungkyunkwan University 300 Chun-chun Dong, Jang-An Gu Swuon, Kyong-Gi Do 440-746 Korea Phone: 82 331 290 7518 Fax: 82 331 290 7549 Email: csyoo@skku.edu Website: http://www.geosyntheticssociety.org/chapters.htm#korean

A Tale of Two Conditions: Heap Leach Pad versus Landfill Liner Strengths Author:   Breitenbach and Thiel   Heap leach facility liner designs have evolved significantly over the last twenty years. In the past, many heap leach liner designs tended to follow a “cookbook” approach without much consideration given to the interaction between the various components such as the foundation, underliner, geomembrane, overliner, and collection piping. It is now generally recognized that the approach to liner design should take into account the behavior of all of the materials that make up the liner system, including materials above the liner such as the solution collection piping, and air injection piping. The advancements in liner design approach have been driven by several factors, including: • Advancements in our understanding of the long-term response of geosynthetics under high loads and very harsh environmental conditions; • The design, construction, and operation of heap leach facilities with significant ore loads [approaching 3 Mega-Pascals (MPa)]; • The construction and operation of very large leach pads that span distances of 5 kilometers across varying foundation materials; • Improvements in understanding solution collection techniques for better recovery and pipe performance; and • The commitment of mining companies to local, national, and international environmental standards. This paper presents an overview of current leach facility liner design approach. Issues, such as the interaction between the various liner design components, are discussed. General guidelines are also presented an discussed.   Publication: Conference Proceedings    Click here for the document   GSA Tech Doc ID #:546

CONTACT INFO: Geosynthetic Institute (GSI) Bob Koerner 475 Kedron Avenue Folsom, PA 19033-1208 United States of America Phone: (610) 522-8440 Fax: +1 (610) 522-8441 Email: robert.koerner@coe.drexel.edu Website: http://www.geosynthetic-institute.org

A Technical Guidance Manual: Terminology, Index & Performance Testing Procedures for Rolled Erosion Control Products Author:   Erosion Control Technology Council -ECTC   This document was originally developed by the ECTC to aid in the understanding and use of the most recent terminology, index/physical property test methods, and performance research for RECPs. It also was intended to assist engineers, geologists, soil scientists, landscape architects, contractors, research facilities within the erosion control industry in the selection of RECPs. The new document continues with these efforts and includes bench scale testing information. It also contains updates to all ASTM standards to reflect the current state of practice.     Click here for the document   GSA Tech Doc ID #:559

CONTACT INFO: Erosion Control Technology Council Laurie Honnigford P.O. Box 18012 W. St. Paul, MN 55118 USA Phone: (651) 450-0559 Email: iagi@iagi.org

A Uniaxial Linear Viscoelastic - Viscoplastic Model for High Density Polyethylene Author:   A. Ghafar Chehab, I.D. Moore   6D Special Session : Durability of Geosynthetics #3. Abstract: A rheological constitutive model, which considers both viscoelastic and viscoplastic components of high density polyethylene behaviour, is developed using data from axial compression tests. A linear viscoelastic model, developed previously, is modified and complemented with a viscoplastic model, and the stress-strain results of five compressive tests at different engineering strain rates are used to determine the model parameters. The ability of the model to predict the response to different loading conditions such as creep, stress relaxation, constant load rates, unloading and strain reversal is examined by comparing the model simulation with the available experimental data. It was found that the model can well predict the response to different loading conditions but is not as accurate in predicting the response to unloading and strain reversal conditions. RÉSUMÉ : Un modèle constitutif rhéologique, qui considère les aspects viscoélastique et viscoplastique du comportement de polyéthylène à haute densité, est développé en utilisant des données des essais de compression axiale. Un modèle viscoélastique linéaire, développé précédemment, est modifié et complété avec un modèle viscoplastique, et les résultats de contrainte-déformation de cinq essais de compression à différentes vitesses de déformation sont employés pour déterminer les paramètres du modèle. La capacité du modèle de prévoir la réponse à différentes conditions de chargement telles que le fluage, la relaxation, le chargement à vitesses constantes, le déchargement et l'inversion de déformation est examinée en comparant la simulation du modèle aux données expérimentales disponibles. Il s’avère que le modèle peut prévoir la réponse aux différentes conditions de chargement mais n'est pas précis en prévoyant la réponse aux conditions d'inversion de déformation et de déchargement.   Publication: GeoQuebec 2004 Conference Proceedings    Click here for the document   GSA Tech Doc ID #:361

A&L Salvage C&D Landfill Case Study Author:   Huesker   An 181-acre construction debris landfill in eastern Ohio presented its owners (and neighbors) with an odor problem. Site aerators were inadequate. The economical solution turned out to be Huesker's Zeomat cover. View the case study by clicking the link below.     Click here for the document   GSA Tech Doc ID #:451

CONTACT INFO: Huesker, Inc. Steve Lothspeich 11107-A South Commerce Blvd. Charlotte, NC 28273 USA Phone: (800) 942-9418 Fax: (704) 588-1462 Website: http://www.hueskerinc.com/

AASHTO M288: Durability Considerations in Standard Specification Documents Author:   Jonathan Fannin   4D Special Session : Durability of Geosynthetics #1 - Introduction - Geotextiles. Abstract: Construction survivability is integral to the selection of a geosynthetic for all construction applications. In many routine applications, where there is no economic rationale for site specific testing, the criterion of construction survivability may be the sole basis for selection of the geosynthetic. Two case studies are reported, from applications in resource engineering, where geotextiles were used in access road construction and streambank stabilisation. The material properties are compared with the default recommendations of AASHTO M288 for highways engineering. Comparison suggests the AASHTO M288 document is suitable for these resource engineering works. Résumé: La serviabilité de construction est intégrale au choix d'un géosynthétique pour toutes les applications de construction. Dans beaucoup d'applications courantes, où il n'y a aucun raisonnement économique pour l'essai spécifique de site, le critère de serviabilité de construction peut être la base seule pour la sélection du géosynthétique. Deux études de cas sont rapportées, des applications dans l'ingénierie de ressource, où des géotextiles ont été employés dans la construction de voie d'accès et la stabilisation de pente de rivière. Les propriétés matérielles sont comparées aux recommandations de défaut d'AASHTO M288 pour génie d’autoroutes. La comparaison suggère que le document d'AASHTO M288 est convenable pour ces travaux d'ingénierie de ressource.   Publication: GeoQuebec 2004 Conference Proceedings    Click here for the document   GSA Tech Doc ID #:352

ACE Basin Parkway Project Under Way Author:   Christina Fisher   A 6.5-mile stretch of U.S. 17 in Beaufort County, South Carolina—one of the most dangerous two-lane roads in the nation—will soon be much safer as a result of the $80.3-million ACE Basin Widening Project. The ACE Basin is a large undeveloped estuary where the Ashepoo, Combahee and Edisto rivers converge. U.S. 17, the Ocean Highway, winds its way through 211 miles of South Carolina and through the historic and environmentally sensitive region of the ACE Basin. The road is in need of dire corrections, but preserving the sensitive habit around it is paramount. And that involves considerable and exemplary use of silt fence and geotextile-wrapped drainage and filtration materials.   Publication: Construction - March 2008    Click here for the document   GSA Tech Doc ID #:594

CONTACT INFO: Reed Construction Data - ACP Christina Fisher Phone: 800 290 6802 Email: cmfisher@reedbusiness.com Website: http://www.acppubs.com/community/835.html

Acoustic Emission in Geologic and Construction Materials Author:   W. Martin McCabe   This paper describes the research into the monitoring of sub audible noises, ie. Acoustic emissions (AE), in soil, rocks and structural concrete that was carried out by Dr. Robert M. Koerner and his associates at Drexel University. The work was preformed in the 1970’s and 1980’s. and was primarily funded by the U.S. Bureau of Mines and the U.S. Department of Transportation Federal Highway Administration. The Vision: Dr. Koerner’s initial collaboration with physicist Dr. Art Lord examined the phenomenon of acoustic emissions produced by soils and the use of AE monitoring to predict failure of slopes and earth embankments. Use of this technique for related earth science stability problems was a natural progression . The objective was to predict roof falls or sidewall instability in open cut or machine-mine tunnels. AE monitoring in underground mines had already been shown to be useful, and the promise of rock slope monitoring was just beginning. The hard, brittle nature of many rock types offered the hope of higher energy, more detectable signals during instability.   Publication: Koerner Symposium 2004    Click here for the document   GSA Tech Doc ID #:341

CONTACT INFO: GSI George Koerner 475 Kedron Avenue Folsom, PA 19033 USA Phone: 610-522-8440 Fax: 610-522-8441 Email: gkoerner@dca.net Website: http://www.geosynthetic-institute.org

Acoustic Emission in Soils and Long Term EPA Funding Author:   Art Lord   I shall try to review the work with Bob Koerner during our EPA-sponsored research on acoustic emissions in soils. This covered the period from 1972-1985. Personal editorial comments will be included. Background: Bob Koerner and I both started at Drexel in September of 1968. We both rode the Media Local commuter train home, and after seeing each other a few (or many) times and realizing we both were at Drexel, we started talking. This was sometime in 1970, I guess. Bob was interested in soil mechanics research and my background was in vibrations in solids. Maybe we could do some mutually interesting research? I am not sure how the subject of acoustic emission (AE) came up, as neither Bob nor I had any experience in or knowledge of it. (The idea of AE might have come from Bob Hay in Metallurgical Engineering, whom we both knew, and I have a faint recollection that Bob H. was involved somehow with AE at this time).   Publication: Koerner Symposium 2004    Click here for the document   GSA Tech Doc ID #:344

CONTACT INFO: GSI George Koerner 475 Kedron Avenue Folsom, PA 19033 USA Phone: 610-522-8440 Fax: 610-522-8441 Email: gkoerner@dca.net Website: http://www.geosynthetic-institute.org

Acoustic Leak Location Author:   Ian Peggs, I-CORP INTERNATIONAL   Ian Peggs provides a tech note on his experience with acoustic leak location.   Publication:  I-CORP INTERNATIONAL    Click here for the document   GSA Tech Doc ID #:328

CONTACT INFO: I-CORP INTERNATIONAL Inc. ( ICORP ) Ian Peggs 6072 N. Ocean Blvd. Ocean Ridge, FL 33435 USA Phone: + 1 561-369-0795 Fax: + 1 561-369-0895 Email: icorp@geosynthetic.com Website: http://www.geosynthetic.com

Activites in GSI-Korea – GCI-PCP of Geogrids Author:   Han-Yong Jeon   The purpose of this paper is to describe GSI-Korea’s method of certifying geogrids in accordance with the Geosynthetic Certification Institute's - Product Certification Program(GCI-PCP) that assesses the manufacturing and quality control systems of manufactured products. In particular it focuses on the certification of uniaxial geogrids manufacturing by the Samyang Corporation of Korea.   Publication: Conference Proceedings    Click here for the document   GSA Tech Doc ID #:548

CONTACT INFO: Geosynthetic Institute (GSI) Bob Koerner 475 Kedron Avenue Folsom, PA 19033-1208 United States of America Phone: (610) 522-8440 Fax: +1 (610) 522-8441 Email: robert.koerner@coe.drexel.edu Website: http://www.geosynthetic-institute.org

Advances in Geosynthetic Reinforced Soil Design Author:   Jorge Zornberg, 2004 IGS Award Recipient   [Editor’s Note: Dr. Jorge G. Zornberg received a 2004 IGS Award at GeoAsia 2004 in Seoul, Korea, for his contributions to “Advances in Geosynthetic Reinforced Soil Design.” The following article was contributed by Dr. Zornberg upon request.] Gone are the days when designs involving geosynthetic reinforcement struggled to demonstrate that these new systems are as reliable as and more cost effective than conventional structures. Instead, today’s challenge is to demonstrate that geosynthetic reinforcement can be used to solve problems deemed unsolvable using conventional systems. These new challenges are being addressed through: (a) advances in design for conventional loads and geometries, (b) advances in design for unconventional loads and geometries, and (c) advances in reinforcement materials. This article comments on some of these advances, which were recognized by this IGS Award.   Publication: IGS News    - Vol:  20  Issue:  3Pages:   16  to   17   Click here for the document   GSA Tech Doc ID #:385

CONTACT INFO: IGS Karina McInnis Project Coordinator eQUIP Task Force Room B411 Mackintosh-Corry Hall, 68 University Ave., Building 164, Queen's University Kingston, Ontario K7L 3N6 Canada Phone: + 1-613-533-3108 Fax: +1 1-613-533-6909 Email: mcinnis@post.queensu.ca

Advances on the Use of Geosynthetics in Hydraulic Systems Author:   Jorge G. Zornberg   Geosynthetic have been used as impervious barriers in dams since 1959 (Contrada Sabetta dam). The use of geosynthetics in hydraulic systems has the potential to grow significantly when compared with the expected growth of the industry in other well established areas such as transportation and environmental systems. While significant advances have taken place in geosynthetics engineering since geomembranes were first used in hydraulic structures, ongoing research and field performance evaluations continue to provide valuable insight. This paper focuses on the current status of the use of geosynthetics in dams both worldwide and in the US as well as on recent advances on the research in this area. Regarding ongoing research, emphasis in this paper is on studies being conducted as part of the Center for Polymers in Hydraulic Systems (CPHyS). This includes evaluation of the durability of geomembranes and the hydraulic performance of geosynthetics under high hydraulic heads.   Publication: Conference Proceedings    Click here for the document   GSA Tech Doc ID #:550

CONTACT INFO: Geosynthetic Institute (GSI) Bob Koerner 475 Kedron Avenue Folsom, PA 19033-1208 United States of America Phone: (610) 522-8440 Fax: +1 (610) 522-8441 Email: robert.koerner@coe.drexel.edu Website: http://www.geosynthetic-institute.org

Agricultural Applications for Geosynthetics Author:   GMA   Some of the earliest geosynthetic specifications in the United States were directed at agricultural use of pond linings for the preservation of water resources. These early application concerns included the lining of ditches, agriculture farm ponds and water harvesting catchments in arid regions. Today, the applications range widely from covered and uncovered ditch linings and ponds to geosynthetic linings that protect groundwater, soils and surface waters from being polluted by animal waste. The use of geosynthetics, and in particular geomembranes, on the farm has come a long way and has grown significantly in recent years, especially with more stringent federal and state legislation as well as increased environmental public awareness through programs developed by the U.S. Department of Agriculture/Natural Resources Conservation Service and U.S. Environmental Protection Agency.     Click here for the document   GSA Tech Doc ID #:217

Agua Fria in Phoenix Uses Enkadrain Instead of Aggregate and Fabric Author:   Colbond   When one thinks about managing severe rain events, one does not often think of doing so in Arizona; yet the state's arid climate is prone to abrupt, harsh rainfalls that cause erosion and drainage problems along major roadways. Colbond's drainage composites provides protection along highway drainage channels. View the case study by clicking the link below.     Click here for the document   GSA Tech Doc ID #:465

CONTACT INFO: Colbond Inc. Richard Goodrum P.O. Box 1057 Enka, NC 28728 USA Phone: (828) 665-5023 Fax: (828) 665-5009 Email: richard.goodrum@colbond.com Website: http://www.colbond-usa.com

Airports: Preventing Pollution During Deicing Author:   Roy McClinton   A mix of geosynthetics controls glycol runoff; protecting groundwater and subsoils, and enabling safer planes in winter conditions. Runoff from glycol deicing operations at airports has long been seen as detrimental to rivers and streams as the decomposition of glycol occurs. As glycol decomposes in water, the biological oxygen demand (BOD) increases, thus depleting the available oxygen that supports aquatic life. This environmental issue is currently being addressed at state and local levels with increased scrutiny, and will likely result in tighter controls on the use of deicing fluids.   Publication: GFR    - Vol:  21  Issue:  1Pages:   28  to   29   Click here for the document   GSA Tech Doc ID #:175

CONTACT INFO: Geosynthetics (formerly GFR) Ron Bygness 1801 County Road B W. Roseville, MN 55113-4061 USA Phone: (651) 225-6988 Fax: (651) 225-6966 Email: rwbygness@ifai.com Website: http://www.ifai.com/Geo/Magazines.cfm

Alternate Daily Covers - Finding the Bottom Line Author:   Neal Bolton   Most folks would agree that alternative daily cover is a good thing for landfills. If used properly, it can save soil, save airspace, and ultimately, save money. Before you can decide what type of alternative daily cover (ADC) you want for your landfill, or indeed whether you want to use ADC at all, you'll have to evaluate the costs and benefits. And, because the decision might not be entirely based on economics, you will also need to look at the pros and cons of various types of ADC.   Publication: MSW Management - June 2004    - Vol:  14  Issue:  4Pages:   52  to   60   Click here for the document   GSA Tech Doc ID #:305

CONTACT INFO: Forester - MSW, Erosion Control, Stormwater, Grading and Excavation John Trotti 2946 De La Vina Street Santa Barbara, CA 93105 USA Phone: (805) 682-1300 Fax: (805) 456-3978 Email: jtrotti@forester.net Website: http://www.forester.net

Aluminium Migration Through a Geosynthetic Clay Liner Author:   C. Lake, G. Cardenas and G. Gagnon   Water treatment plants (WTPs) can produce significant amounts of residual solids (i.e. sludge) as a result of coagulation, flocculation, clarification, and filtration processes to treat raw source water. In North America, alum is a common coagulant used in this process, resulting in the requirement for disposal of significant amounts of alum residual solids. Anticipated improved water quality treatment guidelines for trace metals such as arsenic in North America will result in more alum waste being generated in the future and hence increased pressure on water utilities to examine monofilling of alum-based residual solids to reduce waste management costs. GCLs are a potential cost-effective liner system for this type of application. However, there is currently a paucity of literature related to aluminium migration through GCLs. This paper presents results of GCL hydraulic conductivity, diffusion, and batch testing performed with a simulated WTP monofill leachate. Results of both short term and long term hydraulic conductivity tests show only modest increases in hydraulic conductivity, k, are observed for the tests conditions employed (k< 5x10-11 m/s). Diffusion testing with the same GCL has established an aluminium diffusion coefficient, Dt, of 1.5x10-10 m2/s and a linear distribution coefficient, Kd, of 30 mL/g. Batch testing is used to provide additional insight into the sorption behavior of aluminium with the bentonite from the GCL. Based on the limited results presented herein, it appears as if GCLs are suitable at maintaining low hydraulic conductivity values for at least 12 pore volumes of permeation with the high concentration alum residual monofill leachate simulated in this study. The information presented herein also provides WTP monofill designers with estimates of contaminant migration parameters necessary for establishing “alternative” GCL based liner designs.   Publication: Conference Proceedings    Click here for the document   GSA Tech Doc ID #:543

CONTACT INFO: Geosynthetic Institute (GSI) Bob Koerner 475 Kedron Avenue Folsom, PA 19033-1208 United States of America Phone: (610) 522-8440 Fax: +1 (610) 522-8441 Email: robert.koerner@coe.drexel.edu Website: http://www.geosynthetic-institute.org

Amended and Restated Bylaws of North American Geosynthetics Society Author:   NAGS   Bylaws amended and restated bylaws of North American Geosynthetics Society   Publication: NAGS    Click here for the document   GSA Tech Doc ID #:61

CONTACT INFO: North American Geosynthetics Society NAGS Beth Landen 1801 County Road B West Roseville, MN 55113 USA Phone: (651)225-6952 Fax: (651) 631 9334 Email: blhungiville@ifai.com Website: http://www.nagsigs.org/contact.html

An Evaluation of Potential Clogging of Geonets and Geocomposites Due to Suspended Soil Particles Author:   Dhani B. Narejo   A series of tests were performed to evaluate the flow behavior of soil-water suspensions through synthetic drainage media. The objective of the test program was to determine whether soil particles can get trapped within the drainage medium - leading to clogging - or continue to remain in suspension. A non-plastic soil passing #200 ASTM sieve (finer than 0.075 mm) was mixed with water to prepare mixtures of 0.01 to 1% (100 to 10,000 mg/liter) concentration. This mixture was then used to perform transmissivity tests in equipment that was designed and custom built for these tests. Tests were performed at 0.04, 0.1 and 0.3 gradients. Each test was run on the order of 200 to 300 hours to reach a stable value of transmissivity. The negative effect of particulates on transmissivity, i.e., the clogging of the drainage medium, increased as both the gradient and concentration were increased. The drainage medium remained clean, with no effect on transmissivity, for lower gradients throughout the tested range of concentrations. The results indicate that both the type of flow regime as well as the concentration of suspended solids is important. Most commercial drainage products can handle the range of responses observed, as long as there is not an extremely high concentration of solids.   Publication: Conference Proceedings    Click here for the document   GSA Tech Doc ID #:537

CONTACT INFO: Geosynthetic Institute (GSI) Bob Koerner 475 Kedron Avenue Folsom, PA 19033-1208 United States of America Phone: (610) 522-8440 Fax: +1 (610) 522-8441 Email: robert.koerner@coe.drexel.edu Website: http://www.geosynthetic-institute.org

An Evaluation on Discharge Capacity of Perfabricated Vertical Drains Using Large Scale Test Apparatus Author:   Park, Kim, Jeon   ABSTRACT: Discharge capacity is the most important factor to evaluate the well resistance of prefabricated vertical (PV) drains. In this study, large-scale test apparatus were devised to investigate the accurate discharge capacity of plastic board drain (PBD) and fiber drain (FD). A series of laboratory flow test of PBD and FD has been carried out to evaluate those discharge capacities with same condition in the field. Drain sample length tested ranging from 0.7m to 30m by confining the drain in clay. It is found that discharge capacity qw of PV drains decreases with increasing the confining pressure, the hydraulic gradient, and drain length. It is strongly recommended that for determining the design value of qw and kw the discharge capacity test should be performed using a half sample length of real field depth. It is found out that well resistance calculated from Onoue’s equation is underestimated comparing to that of Hansbo’s one.   Publication: 3rd Asian Regional Conf on Geosynthetics    Click here for the document   GSA Tech Doc ID #:291

CONTACT INFO: IGS Korea Chungsik Yoo Sungkyunkwan University 300 Chun-chun Dong, Jang-An Gu Swuon, Kyong-Gi Do 440-746 Korea Phone: 82 331 290 7518 Fax: 82 331 290 7549 Email: csyoo@skku.edu Website: http://www.geosyntheticssociety.org/chapters.htm#korean

An Old But New Issue; Viscous Properties of Polymer Geosynthetic Reinforcement and Geosynthetic-Reinforced Soil Structures Author:   Tatsuoka, Hirakawa, et al   Tatsuoka, Hirakawa, Shinoda, Kongkitkul, and Uchimura. Abstract: Viscous deformation characteristics of geosynthetic as well as those of backfill and geosynthetic-reinforced soil structures are discussed based on results from laboratory load/stress-strain tests of geosynthetic and backfill as well as behaviours of small-scaled reinforced soil models and proto-type full-scale geosynthetic-reinforced soil structures and associated numerical simulations of experimental results, including FE simulations. The following remarks are presented: a) creep is not a degrading phenomenon with both geosynthetic and backfill, while the isochronous concept is not able to relevantly predict the load/stress-strain time behaviour of geosynthetic as well as soil and reinforced backfill subjected to arbitrary loading histories; b) a non-linear three-component rheology model is relevant to represent the viscous properties of geosynthetic and backfill; and c) tensile force in the geosynthetic arranged in the backfill subjected to sustained loading could decrease with time in ordinary field cases, where the safety factor against ultimate failure of the structure is sufficiently high. The design rupture strength of geosynthetic obtained using a relatively larger creep reduction factor determined based on the conventional creep rupture curve could be overly conservative. An alternative design procedure is tentatively proposed. It is demonstrated that the creep deformation rate substantially decreases; therefore the possibility of creep rupture of geosynthetic reinforcement can be eliminated, by applying a relevant preloading history.   Publication: 3rd Asian Regional Conf on Geosynthetics    Click here for the document   GSA Tech Doc ID #:266

CONTACT INFO: IGS Korea Chungsik Yoo Sungkyunkwan University 300 Chun-chun Dong, Jang-An Gu Swuon, Kyong-Gi Do 440-746 Korea Phone: 82 331 290 7518 Fax: 82 331 290 7549 Email: csyoo@skku.edu Website: http://www.geosyntheticssociety.org/chapters.htm#korean

An Overview of the Functions and Applications of Cellular Geosynthetics Author:   John S. Horvath   From the International e-Conference on Modern Trends in Foundation Engineering: Geotechnical Challenges and Solutions. Abstract: Cellular geosynthetics is the generic term used nowadays to describe geosynthetic materials with either closed- or open-cell texture. This includes the geosynthetic product families of geofoams and geocombs which are the focus of this paper. Although the use of cellular geosynthetics actually dates back to at least the 1960s, it was not until their worldwide emergence during the 1990s that they began to revolutionize geosynthetics technology and have a noticeable impact on engineered construction. This is because cellular-geosynthetic products offer a wide range of geosynthetic functions that, with few exceptions, were heretofore unavailable from traditional planar geosynthetics such as geogrids, geomembranes and geotextiles. This paper provides a concise summary of geofoam and geocomb materials and products that are available currently, and presents a summary of their functions and typical applications.     Click here for the document   GSA Tech Doc ID #:573

CONTACT INFO: Manhattan College Center for Geotechnology John Horvath Email: john.horvath@manhattan.edu Website: www.manhattan.edu/~jhorvath

Analysis and Design of EPS- Geofoam Embankments for Seismic Loading Author:   Hany L. Riad, John S. Horvath   The use of block-molded expanded polystyrene (EPS-block) geofoam as a lightweight-fill material for highway embankments is a relatively mature geotechnology with more than 30 years history of successful application worldwide. Basic analysis and design procedures are now well established and documented, and current research and development efforts are focused on making incremental improvements. One such area of improvement relates to analysis and design for seismic loading. The recent construction of several EPS-geofoam highway embankments on the Central Artery/Tunnel (CA/T) Project in Boston, well known as the 'Big Dig', resulted in an opportunity to advance the state of practice for EPSgeofoam embankments subjected to seismic loading. In particular, a newly recognized behavioral mode referred to as seismic rocking was identified and found to govern the design of these fills for internal stability. This behavioral mode is described in this paper in the context of summarizing the current state of knowledge with respect to seismic analysis and design of EPS embankments.   Publication: Geo-Trans 2004 - Proceedings    Click here for the document   GSA Tech Doc ID #:585

Analysis of Equipment Loads on Geocomposite Liner Systems Author:   David J. Kerkes   The loads imposed on geosynthetics during installation are frequently the most severe that the materials will experience during their service life; however, they are among the most difficult to evaluate. This paper examines the loads imposed by track mounted and rubber tired vehicles spreading soil over the liner system during construction and proposes an analysis that uses three- dimensional sliding blocks for computing a factor of safety for the liner system under such loads, which takes into account the effect of the soil cover between the equipment and potential failure surface, as well as the effect of tensile forces in components of the liner above that surface. The solution algorithm, which is presented in some detail, can be executed using standard spreadsheet software. The limitations of the method are also discussed, and suggestions are made for using the method in light of the complex stress-strain behavior of composite liner systems.   Publication: Geosynthetics '99    Click here for the document   GSA Tech Doc ID #:437

CONTACT INFO: IFAI Bookstore Sue Damico 1801 W. County Rd. B Roseville, MN 55113-4061 United States Phone: 651-631-9334 Fax: 651-225-6913 Email: smdamico@ifai.com Website: http://www.bookstore.ifai.com

Application of Numerical Modelling to the Design of Reinforced Soil Walls for Infrastructure Projects - Some Australian Experiences Author:   S.R. Lo   ABSTRACT: The use of geosynthetic reinforcement encourages innovation in the design of reinforced soil walls. However, conventional design rules may no longer be adequate for these innovative wall configurations. Numerical analyses contribute to the design of these innovative walls even under severe project constraints. Two cases are reviewed, with the second one being studied in detailed.   Publication: 3rd Asian Regional Conf on Geosynthetics    Click here for the document   GSA Tech Doc ID #:275

CONTACT INFO: IGS Korea Chungsik Yoo Sungkyunkwan University 300 Chun-chun Dong, Jang-An Gu Swuon, Kyong-Gi Do 440-746 Korea Phone: 82 331 290 7518 Fax: 82 331 290 7549 Email: csyoo@skku.edu Website: http://www.geosyntheticssociety.org/chapters.htm#korean

Application of Porous ("Leaky") Rock Terminal Structures Author:   Tensar - Erik Olsen and Kevin Bodge   A major structural stabilization project was constructed in 2004 at the southerly terminus of Amelia Island, a 15.2 km long coastal barrier located in northeast Florida. The goal of the project was to reduce end loses from a 5.6 km updrift beach restoration project without adversely affecting the sediment trasnsport required to maintian the downdrift, inlet-facing shoreline. The constructed project consists of a 465-m long "leaky" terminal groin and a 93-m long detached breakwater, both built of rock. The groin is purposefully low and porous to allow passage of some littoral drift, and the breakwater is designed to augment beach stability at a shoreline "hinge point" updrift of the groin. Through August 2006, the project has met or exceeded the performance objectives.     Click here for the document   GSA Tech Doc ID #:577

CONTACT INFO: Tensar Earth Technologies Gale Sanders 5883 Glenridge Drive Suite 200 Atlanta, GA 30328-5363 USA Phone: + 1 404-214-5350 Fax: + 1 404-250-0461 Email: gsanders@tensarcorp.com Website: http://www.tensarcorp.com

Applications of Waste Pretreatment to Landfill Operations in South Africa Author:   M. Griffith and C. Trois   Despite international trends, landfilling of untreated and unsorted waste is still the most common practice in South Africa. This waste management strategy, particularly when applied in subtropical regions, proves to be unsustainable due to persistent polluting potential. The efforts towards waste reduction can benefit from the introduction of Mechanical Biological Pretreatment (MBP) prior to disposal (Leikam and Stegmann, 1997). A desktop study on various waste pre-treatment techniques has indicated the Dome Aeration Technology (DAT) as appropriate for South Africa (Griffith, 2005), in relation to low capital costs, low energy inputs, limited plant requirements and potential for labour-based operations. This paper reports on the performance of three fullscale DAT windrows (30mx10mX2m) set up at the Bisasar Road Landfill in Durban, in order to study the efficiency of the process for different composting times (8 and 16 weeks). The construction and operation techniques adopted in Durban were based on the experience of the Cottbus and Plauen landfills in Germany, where post-treatment of residues from high-tech MBWT (with refractory-organic fine fraction remaining) is achieved to EU standards in only 3 to 4 months, with no turning. The performance of the Durban windrows was compared with the German results to assess the influence of climate, waste composition and operational facilities. In a second stage, the “post-landfilled” behaviour of the pre-treated material was analysed in anaerobic lysimeters. The success of the DAT in emerging countries, as South Africa, was found directly dependant on the mechanical treatment steps, available operational facilities and a careful selection of the input material.   Publication: Landfill 2005 Conference Proceedings    Click here for the document   GSA Tech Doc ID #:484

CONTACT INFO: GIGSA Peter Davies 11 Livingstone Road PO Box 116 Pinetown, Kwazulu-Natal 3600 South Africa Phone: +27 31 701 0352 Fax: +27 31 702 4477 Email: nphuntpld@kaymac.co.za

Approach Embankment Supported by Geotextile Reinforced Sand Platform over Vibro Concrete Columns- A Case Study Author:   R. Wilson-Fahmy, S. Hanna & R. Mankbadi   This paper discusses the design and construction of the foundation for a bridge approach embankment which consists of back-to back mechanically stabilized earth walls (MSE) constructed within a wetland area. The walls are highest at the bridge abutment with a maximum height of 10 meters. Soil improvement was undertaken to provide suitable foundation for the approach embankment. The soil improvement consisted of installation of vibro concrete columns (VCC) penetrating the soft soil into suitable sandy soil layers in conjunction with a geotextile reinforced sand platform to transfer the embankment fill load to the VCC. This solution constituted the first use of VCC by a US Department of Transportation to support an approach embankment. The design concept of the embankment supporting system is outlined. However, emphasis is given to the behavior of the geotextile component of the system. The performance of the embankment supporting system is assessed based on monitoring data obtained from various instruments installed during construction including settlement platforms, probe extensometers, inclinometers, piezometers and strain gages attached to the sand platform geotextile reinforcing elements.   Publication: Conference Proceedings    Click here for the document   GSA Tech Doc ID #:516

CONTACT INFO: Geosynthetic Institute (GSI) Bob Koerner 475 Kedron Avenue Folsom, PA 19033-1208 United States of America Phone: (610) 522-8440 Fax: +1 (610) 522-8441 Email: robert.koerner@coe.drexel.edu Website: http://www.geosynthetic-institute.org

Asperity Height Variability and Effects Author:   Nathan Ivy   Almost since the introduction of GRI-GM 12, Asperity Measurement of Textured Geomembranes Using a Depth Gage, there have been complaints throughout the industry concerning variability associated with asperity height test results and schools of thought concerning the effects of increased asperity height on shear strength. The two main categories of variability are incorrect test procedures and manufacturing variability of textured geomembranes. Additional concern has been voiced within the last few years over the practice of pushing asperity heights higher and higher. The general consensus has been that dramatically higher asperity heights will produce dramatically higher direct shear results. This does not appear to be the case; in fact, dramaticallyhigher asperity heights have profoundly negative effects on tensile properties —uniaxial and multiaxial, in both elongation and strength.   Publication: GFR - October 2003    - Vol:  21  Issue:  8Pages:   28  to   29   Click here for the document   GSA Tech Doc ID #:200

CONTACT INFO: Geosynthetics (formerly GFR) Ron Bygness 1801 County Road B W. Roseville, MN 55113-4061 USA Phone: (651) 225-6988 Fax: (651) 225-6966 Email: rwbygness@ifai.com Website: http://www.ifai.com/Geo/Magazines.cfm

Asphalt Reinforcement with Geosynthetics/Asphalt Reinforcement with Geosynthetics Author:   Joel Sprague TRI   Stress relief for cracked pavement using geosynthetic material. The benefits of geosynthetic interlayers.   Publication: TRI/Environmental Lab Updates    Click here for the document   GSA Tech Doc ID #:38

Asphalt Retention: Is this the key to long-term effectiveness of paving fabrics? Author:   Joel Sprague   The Problem: Deteriorating Asphalt Pavements Cracking is the most widespread type of destruction of asphalt concrete pavements. Maintenance measures to repair cracking include patching, sealing, milling, re-paving, and overlays. Although overlays are frequently utilized as a method of repair, reflective cracking, or the propagation of the original cracks into the new overlay, has been a major stumbling block. The occurrence of reflective cracking and the subsequent penetration of water into the pavement sub-layers are the primary cause of rapid deterioration of pavement overlay systems. The most important factor in extending the life of pavement, therefore, is the reduction of water infiltration. The FHWA reports that up to 50% of water falling on asphalt and 67% on concrete can penetrate the road structure. These percentages apply to undamaged pavement. As pavement cracks and deteriorates, the percentages approach 100% infiltration or all the water entering the structure. Since saturation for merely 10% of the time can reduce the life expectancy of a pavement by 50%, it is imperative that an attempt be made to waterproof the pavement. Paving fabrics have the potential, when designed and installed properly, to retard reflective cracking and provide a moisture barrier that prevents water from penetrating the road structure both before and after cracking. Paving fabrics effectively control many types of cracking.   Publication: TRI/Environmental Lab Updates    Click here for the document   GSA Tech Doc ID #:58

CONTACT INFO: TRI/Environmental, Inc. ( TRI ) Joel Sprague P.O. Box 9192 Greenville, SC 29604 USA Phone: (864) 242-2220 Fax: (864) 242-3107 Email: cjoelsprague@cs.com Website: http://www.geosynthetictesting.com

Assessment and Recommendations for Improving the Performance of Waste Containment Systems - EPA 600/R-02/029 Author:   Bonaparte, Daniel and Koerner Document ID:   EPA 600/R-02/029   This broad-based study addressed three categories of issues related to the design, construction, and performance of waste containment systems used at landfills, surface impoundments, and waste piles, and in the remediation of contaminated sites. Geosynthetic materials have been used as essential components of waste containment systems since at least the early 1980's, and this report represents the first attempt to gauge their performance. Specifically the report addresses long-term performance: Geosynthetic Technical Issues - 1) protection of geomembranes from puncture using needlepunched nonwoven geotextiles 2) behavior of waves in high density polyethylene (HDPE) geomembranes when subjected to overburden stress 3) plastic pipe stress-deformation behavior under high overburden stress 4) service life prediction of geotextiles and geomembranes. Natural Soil Technical Issues - Geosynthetic clay liners (GCLs) are a relatively new type of liner material, having first been used in a landfill in 1986. One of the key issues with respect to field performance of GCLs is their stability on permanent slopes, such as found on landfill final cover systems. Fourteen test plots, designed to replicate typical final cover systems for solid waste landfills, were constructed to evaluate the internal and interface shear strength of GCLs under full-scale field conditions on 2H:1V and 3H:1V slopes. Five different types of GCLs were evaluated, and performance was observed for over four years. All test plots were initially stable, but over time, as the bentonite in the GCLs became hydrated, three slides (all on 2H:1V slopes) that involved the GCLs have occurred. Field Performance - To evaluate the field performance of compacted clay liners (CCLs), a database of 89 large-scale field hydraulic conductivity tests was assembled and analyzed. A separate database for 12 soil-bentonite admixed CCLs was also assembled and analyzed. In addition, case histories on the field performance of CCLs in final cover test sections were collected and evaluated.   Publication: EPA 600/R-02/029    Click here for the document   GSA Tech Doc ID #:418

CONTACT INFO: United States Environmental Protection Agency ( EPA ) David Carson Cincinnati, OH 45268 USA

Assessment of Geosynthetics Interface Friction for Slope Barriers of Landfill Author:   Gourc , Reyes-Ramirez, Villard   ABSTRACT: Stability of Geosynthetic Lining Systems is, for a geotechnical standpoint, a complex matter. Three geomechanical questions were identified: sliding of the geosynthetic lining system on slope, pull-out strength of the geosynthetic anchorage at the top of the slope, rain erosion of the cap cover. Research programmes carried out in France on these topics, , are presented. Use of laboratory facilities (mainly different Inclined Planes) and large scale experimentations on actual slopes is especially emphasized. The observations derived from the tests and their detailed interpretation are really fruitful, as they highlight specific local interaction behaviour between soil and geosynthetics, which are not taken into account in design methods, more particularly wrinkles and real relative displacements of geosynthetics along the slope (Chapter 2), realistic value of interface friction angle (Chapter 3 ), pull-out strength of a “L-shape” anchorage (Chapter 4), identification of the mechanisms of control of erosion by geosynthetics (Chapter 5).   Publication: 3rd Asian Regional Conf on Geosynthetics    Click here for the document   GSA Tech Doc ID #:272

CONTACT INFO: IGS Korea Chungsik Yoo Sungkyunkwan University 300 Chun-chun Dong, Jang-An Gu Swuon, Kyong-Gi Do 440-746 Korea Phone: 82 331 290 7518 Fax: 82 331 290 7549 Email: csyoo@skku.edu Website: http://www.geosyntheticssociety.org/chapters.htm#korean

Assessments of Long-Term Drainage Performance of Geotextiles Author:   Han-Yong Jeon and Jacek Mlynarek   4D Special Session : Durability of Geosynthetics #1 - Introduction - Geotextiles. Abstract: Drainage performance of nonwoven geotextiles was examined in consideration of the values for reduction factors and these values are tempered by the site-specific conditions. Two types nonwoven geotextiles- typical and hybrid types-, which are widely applied as drainage materials to the civil engineering fields in Korea were used to compare the drainage performance. For this case, the flow rate of these geotextiles were decreased with reduction factors but the degree of decrease for hybrid type geotextiles were very lower than those of typical type nonwoven geotextiles. Allowable flow rates of geotextiles were mainly influenced by the reduction factors of soil clogging and creep reduction of voids. Hybrid type geotextiles have more stable and excellent drainage performance than typical type geotextiles.   Publication: GeoQuebec 2004 Conference Proceedings    Click here for the document   GSA Tech Doc ID #:350

Assuring the Quality of HDPE Geomembrane Liners: An International Perspective Author:   Ian Peggs   The use of geomembranes for the containment of solid and liquid waste, for the collection, containment, and conveyance of water, for the pollution protection of groundwater, and for corrosion protection is growing rapidly internationally. The geomembrane of choice, also internationally, is high density polyethylene (HDPE). There is approximately 30 years of experience with HDPE, during which there have expectedly been a number of failures and problems, but from which much has been learned. Consequently, significant improvements in liner materials, installation practices, and testing have been made, which have led to the development of effective quality programs at different stages of a liner installation project. Such programs are necessary since geotechnical and civil engineers, regulators, and general contractors are not thoroughly familiar with the performance characteristics of viscoelastic engineering polymer products. A series of comprehensive integrated Quality Control and Quality Assurance programs are outlined that potentially provide optimum assurance that a liner is adequately designed, specified, manufactured, installed, tested, and placed in service. With an integrated quality program there is no reason that the service period should not exceed several hundred years.     Click here for the document   GSA Tech Doc ID #:210

CONTACT INFO: I-CORP INTERNATIONAL Inc. ( ICORP ) Ian Peggs 6072 N. Ocean Blvd. Ocean Ridge, FL 33435 USA Phone: + 1 561-369-0795 Fax: + 1 561-369-0895 Email: icorp@geosynthetic.com Website: http://www.geosynthetic.com

Back Drainage Design and Geocomposite Drainage Materials Author:   Koerner, Soong and Koerner   This paper on geosynthetic reinforced segmental retaining walls (SRW’s) focuses on drainage pressures, quantification and design beneath and behind (or within) the reinforced soil zone of the SRW. This is an important consideration because the majority of problems with SRW’s (in 20 out of 26 case histories) were brought about by low permeability backfill soils in the reinforced zone. Without proper drainage, hydrostatic and/or seepage pressures have resulted in forces which can deform or even fail the entire wall system. A design method based on a finite difference code is presented. It results in the determination of the seepage pressures, as well as quantification of the required flow rate for a given set of conditions. When this value is compared to the allowable flow rate for a candidate drainage product, a flow rate factor of safety is obtained. The entire design process is numerically illustrated for ten different geosynthetic drainage materials. The conclusion reached is that if low permeability soils are used for backfill in the reinforced soil zone, drainage behind the zone must be provided. There are numerous geosynthetic drainage materials that are available, as well as the use of free draining soil materials. All of these drainage systems are readily designable and constructible. While there will be an increase in cost, the increase is not felt to be prohibitive in light of the currently low cost of SRW’s. Conversely, the cost of a failure is certainly prohibitive and must be avoided.   Publication: Conference Proceedings    Click here for the document   GSA Tech Doc ID #:510

CONTACT INFO: Geosynthetic Institute (GSI) Bob Koerner 475 Kedron Avenue Folsom, PA 19033-1208 United States of America Phone: (610) 522-8440 Fax: +1 (610) 522-8441 Email: robert.koerner@coe.drexel.edu Website: http://www.geosynthetic-institute.org

Behavior of Soils Around the Geogrid During Pullout Test Author:   Kuwano, Izawa, Hayashi   ABSTRACT: This paper discusses the behavior of soils around the geogrid during pullout test. For that purpose, the new pullout test apparatus was developed. The sidewall of it is made of transparent acryl plate so that the deformation of the soil around the geogrid can be monitored directly. In this test series, measurement targets were plotted on the flexible membrane sheet that was attached to the acryl plate. By measuring the coordinate of targets, the deformation was observed. In this study, three samples with different particle size were used in order to clear the detailed mechanism of deformation. As a result, the larger area was deformed in sand with larger particle size. Therefore, it was found that the op was affected by soil properties itself and the ratio of tan op tan o was proportional to the log D50.   Publication: 3rd Asian Regional Conf on Geosynthetics    Click here for the document   GSA Tech Doc ID #:297

CONTACT INFO: IGS Korea Chungsik Yoo Sungkyunkwan University 300 Chun-chun Dong, Jang-An Gu Swuon, Kyong-Gi Do 440-746 Korea Phone: 82 331 290 7518 Fax: 82 331 290 7549 Email: csyoo@skku.edu Website: http://www.geosyntheticssociety.org/chapters.htm#korean

Bekanntgabe der Prüfbedingungen für Geokunststoffe in Zulassungsverfahren des Eisenbahn-Bundesamtes ( Test Conditions for Geosynthetics in Approval Procedures of the Eisenbahn-Bundesamt ) Author:   Eisenbahn-Bundesamtes ( EBA )   The EBA (Eisenbahn-Bundesamt), or federal office for railways in Germany, has issued a new guideline Bekanntgabe der Prüfbedingungen für Geokunststoffe in Zulassungsverfahren des Eisenbahn-Bundesamtes (Test Conditions for Geosynthetics in Approval Procedures of the Eisenbahn-Bundesamt) that became effective on 31 May 2003. Naue Fasertechnik (a gsa Underwriter) has since received EBA approvals for seven of their products. Please note that the document at the link below is in German.   Publication: TM 139/2003/005    Click here for the document   GSA Tech Doc ID #:314

Bentofix Sealing at Toulouse-Blagnac Airport