Geomembrane Articles on Environmental XPRT

Axisymmetric Tension Testing of Geomembranes

The newly developed axisymmetric tension test is useful in evaluating the performance of geomembranes subjected to out-of-plane stress conditions such as those that can develop due to localized subsidence under waste-containment cover and liner systems. In this paper, the equations necessary to describe the geomembrane stresses and strains during testing are derived, and equations used to ...

Sep. 1, 1993

By ASTM International

Examining the benefits of HDPE geomembrane

Comparing various geomembranes for your next geosynthetic application? Don’t overlook high-density polyethylene (HDPE) geomembrane. HDPE has been in use for decades and during that time a number of studies have been conducted to test its longevity and ability to meet environmental sustainability project requirements. Here, we explore some of those studies to examine the benefits of HDPE ...

Jan. 26, 2017

By Agru America, Inc.

Numerical modeling of geomembranes

SoilVision Systems Ltd. is pleased to announce the addition of internal boundary conditions which can be used to represent geomembrane materials. The new feature was implemented in response to requests from customers and represents a significant improvement for the numerical modeling of a number of different scenarios involving geomembranes. More specifically, the geomembrane internal boundary ...

May 13, 2010

The Lighter Side of Geomembranes

Geomembrane installations often cover substantial areas. Landfill cells pose enormous footprints. Oil and gas pits, industrial processing ponds, and wastewater containment ponds are large installations too, and each year they tend to be built a little larger. The scaling up of these facilities is not just a matter of achieving better operational economics for the ...

Sep. 7, 2016

By Nilex

Enhanced Geomembrane CQA through proper application of geomembrane leak location surveys

Abstract Historically, geomembrane construction quality assurance (CQA) has focused on destructive testing of welded seams to verify seam strength and integrity. Paradoxically, seams are not subject to significant stress and practically never fail in service, while holes and construction damage in the geomembrane are a much more widespread problem. The historical approach fails to evaluate ...

Jan. 1, 2007

By Leak Location Services Inc. (LLSI)

Strain Measurement in HDPE Geomembrane Tensile Tests

According to ASTM D 638, the tensile strain in an HDPE geomembrane dumbbell specimen subjected to a tensile test should be evaluated using an extensometer that records the elongation of a defined length of the central portion of the specimen. However, the current practice in the United States for HDPE geomembrane quality control and conformance testing consists of following the 1991 NSF standard ...

Mar. 1, 1994

By ASTM International

Locating Geomembrane Liner Leaks under Waste in a Landfill

Abstract An Electrical Leak Imaging and Monitoring (ELIM SM) survey was used to locate leaks under 2.5 meters of stabilized waste in an active geomembrane-Iined landfill. The landfill is lined with two 2-mm thick HDPE geomembranes that are separated by a geonet drainage layer. The primary liner is covered with 600 mm of drainage sand and 2.5 meters of stabilized waste for a total cover ...

Jun. 19, 1997

By Leak Location Services Inc. (LLSI)

Geomembrane protection - Case Study Summary 1

Protecting geomembranes is critical to their long-term performance in many applications including lagoons, detention ponds, storm water containment basins, dikes, temporary dams and landfill covers. The Geoweb® system, with a variety of infills, will provide armor protection to impervious liners or covers so that they can maintain their integrity. Inclusion of internal tendons and ...

Jun. 9, 2009

By Presto Geosystems

Anaerobic digester proves ideal application for EPDM Geomembrane

AS demand increases for environ-menially friendly energy sources, renewable energy companies like Highmark Renewables, located in Vegreville, Alberta, are utilizing an up-and-coming energy source: anaerobic digesters using animal waste. While animal waste anaerobic digesters have been part of the European landscape for many years-including facilities in Austria, Belgium, Germany, Holland and ...

Nov. 1, 2007

By Himark bioGas Inc

Costs and Benefits of Geomembrane Liner Installation CQA

ABSTRACT Because the cost of third-party construction quality assurance (CQA) of geomembrane liner installations is typically comparable to the cost of the geomembrane liner, CQA must be optimized to obtain the most benefit for the owner, rate payers, and environment. A regulation-based CQA protocol usually includes testing the material, observing the quality control (QC) program of the ...

Jun. 14, 2014

By Leak Location Services Inc. (LLSI)

Time-Temperature Superposition in Mechanical Durability Testing of Polyethylene Geomembranes

The mechanical durability of polyethylene geomembranes is considered in this technical note. Polyethylene plastic pipe research has shown that there are universal factors for shifting high-temperature failure (short time) data to low temperatures (long time). Data presented here indicate that these same shift factors may also apply to geomembranes. Crack growth rate studies are proposed as a ...

Jun. 1, 1993

By ASTM International

Size Effects for Multi-Axial Tension Testing of HDPE and PVC Geomembranes

Geosynthetics may be subjected to multi-axial stress states from plane strain loading, such as dragdown along lined slopes and from out-of-plane loading conditions imposed by localized subsidence beneath waste containment cover and liner systems. The multiaxial tension test is useful in evaluating the performance of geosynthetics subjected to multi-axial stress states. However, widespread ...

Dec. 1, 1995

By ASTM International

Performance-Based Specification Of Electrical Leak Location Surveys For Geomembrane Liners

ABSTRACT Electrical leak location surveys can be a crucial part of the final quality control of geomembrane liner installations. The method has been offered as a commercial service since 1985 and is the only practical test method that can find holes in the liner after protective soil cover is put on the liner. During the past fourteen years the test method has been used on a wide variety of ...

Jun. 14, 2014

By Leak Location Services Inc. (LLSI)

Experience with GCLs used as a conductive layer in geomembrane leak-location surveys

Engineers, installers, regulators, and owners are starting to rely on geomembrane leak-location surveys as part of the construction quality assurance for landfills. The various methods are described in ASTM Standard D 6747.' Standard procedures for conducting leak-location surveys of geomembranes covered with earth materials are described in ASTM Standard D 7007.2 Figure 1 shows the ...

Jun. 1, 2007

By Leak Location Services Inc. (LLSI)

Notched Constant Tensile Load (NCTL) Test for High-Density Polyethylene Geomembranes

A modification of an old test method, the notched constant tensile load (NCTL) test, is reintroduced to evaluate the stress-cracking performance of high-density polyethylene (HDPE) geomembranes. In this modified test, notched dumbbell-shaped specimens are subjected to a range of constant tensile loads in a 10% Igepal (CO-630) solution at 50°C. The method has been proposed to ASTM and is being ...

Dec. 1, 1993

By ASTM International

Detection and Location of Leaks in Geomembrane Liners Using an Electrical Method: Case Histories

ABSTRACT A field-proven electrical technique, developed at Southwest Research Institute, San Antonio, Texas, is commercially available to detect and locate leaks in geomembrane liners. The electrical technique is used to inspect 100% of the geomembrane material that is covered by a conducting liquid. A voltage applied across the liner produces a uniform electrical potential distribution in ...

Jun. 14, 2014

By Leak Location Services Inc. (LLSI)

Locating Leaks in Geomembrane Liners of Landfills Covered With a Protective Soil

ABSTRACT The electrical leak location method was used to locate leaks in the geomembrane liners of single-lined and double-lined landfills covered with a protective soil cover. The landfills ranged in size from 0.40 hectare (one-acre) to 3.2 hectares (eight-acre). Water in the leak detection system under the primary liner indicated the primary liners were leaking. The principal of ...

Jun. 14, 2014

By Leak Location Services Inc. (LLSI)

Rainstore3 Installation Instructions Water Harvesting For Stormwater Drainage Containment & Reuse with Geomembrane Liner

This document describes how to properly install the Rainstore3 water storage system with geomembrane for stormwater containment and reuse. Containment allows for on site subsurface water storage for many non-potable applications such as irrigation. Contractors: Only licensed contractors should install the Rainstore3 system. The contractor should have a good performance record with similar ...

Jun. 28, 2011

By Invisible Structures, Inc.

Evaluation of geomembrane, amended soil and composite liner system as lining materials for chromium decontamination in landfill site

A comprehensive laboratory and field–scale study was performed to explore the efficacies of geomembrane, amended soil liner material and composite liner packs for using as containment liner systems for attenuating chromium transport emanating from a chrome laden solid waste disposal site. Soil samples were collected from the site and were admixed with different amended materials, such as rice ...

Sep. 26, 2012

By Inderscience Publishers

Specifying allowable leakage rates

Introduction Allowable Leakage Rates or Action Leakage Rates (ALRs) are specified for installed geomembranes to quantify the maximum allowable liquid leakage. If the ALR is exceeded, corrective action must be taken to reduce the leakage rate below the set limit. To lower the leakage, the holes in the geomembrane are located and repaired. In some cases, the ALR is set so low that, ...

Aug. 1, 2011

By Leak Location Services Inc. (LLSI)

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