The durability of exposed geomembrane covers

October 1, 2017  |  Features

The most frequently asked question by people in the geosynthetics world is how long is the anticipated lifetime of geosynthetics. So much so that of the more than 3,000 questions submitted to the GMA Techline since it began in 2004, 591 (19.7%) have been on lifetime, aka durability. Of these, 49% we…
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GMA Techline

October 1, 2017  |  Features, News, Q&A: GMA Techline

Welding HDPE to PVC and more Q: I would appreciate any input you have on these questions: Can a high-density polyethylene (HDPE) geomembrane (GM) be welded to a PVC geomembrane? I am looking to connect a geomembrane to a building foundation. Based on some research, I have found the following options…
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Part 2: The regulation of CCR in the United States: Geosynthetics and barriers

October 1, 2017  |  Features

As discussed in Part 1 of “The Regulation of CCR in the United States,” for the first time in decades, nationwide regulation of CCR (coal combustion residuals) surface impoundments expands the regulated use of geosynthetic materials. While the CCR Rule (2015) allows continued operation of existi…
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Part 1: The regulation of CCR in the United States: Geosynthetics and barriers

August 1, 2017  |  Features, News

The regulation of coal ash (coal combustion residuals or CCR) has significantly expanded the market for geosynthetics within the United States. Further, there is interest in these regulations around the globe in every country using coal as an energy source. These regulations are the result of recent…
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GMA Techline

August 1, 2017  |  Features, News, Q&A: GMA Techline

Liner repair? Pullout tests? Sewn seams? Shear strength of sludges? Geomembrane liner repair Q: I have a facility that has submitted liner repair documentation for the repair of a high-density polyethylene (HDPE) liner for a leachate/stormwater pond at an industrial landfill site. The repairs were p…
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CCR management using geotextile tubes

August 1, 2017  |  Features, News

Introduction Since the late 1800s, coal has played a leading role in U.S. production of electrical energy. Coal-fired power plants have provided reliable electrical power from the earliest days when power plants were run with hand-fed coal to heat boilers to produce steam. The introduction of pulver…
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Using geosynthetics for macroencapsulation for CCR on-site clean closure

August 1, 2017  |  Features, News

Coal combustion residuals (CCR) have been used for many years in the construction of berms and engineered structural fill applications, including embankments for highways, dikes, and levees. However, large, unencapsulated structural fill projects have become a focus of environmental concerns due to …
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History of geosynthetics use on national forest roads

June 1, 2017  |  Case Studies, Features

Introduction The objectives of this article are to document the long history of geosynthetic materials used in the U.S. Department of Agriculture (USDA) Forest Service and other rural roads, to document the many creative and useful ways geosynthetics have been used, and to promote the cost-effective…
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PART 2 Functions and applications of geosynthetics in roadways

April 1, 2017  |  Features

Introduction Part 1 of this article provided an overview of the various functions that geosynthetics can fulfill in roadway applications. These functions include separation, filtration, reinforcement, stiffening, drainage, hydraulic/gas barrier, and protection. Table 1 in that article identified a t…
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PART 1 ‘Geosynthetic reinforced soil 101’ leading to rational design of MSE walls and slopes

April 1, 2017  |  Features

Introduction The design of many geotechnical structures is based on limit state conditions. For example, in designing gravity walls, the load exerted by the retained soil on the wall is based on an assumed active state of stresses. That is, the wall moves sufficiently outward, enabling the retained …
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