Update from IGS-NA

April 1st, 2021

by John Allen The IGS North America (IGS-NA) board is working diligently on diversity within its membership and representatives. The organization is expanding the number of liaisons to the board to include all the major North American technical societies that influence geosynthetics. IGS-NA provides the best vehicle for disseminating research on geosynthetics, as it connects […]

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GMA Techline: Geomembranes for reinforcement?

April 1st, 2021

Q: We are using Robert Koerner’s Designing with Geosynthetics to calculate the required thickness of a geomembrane. See Figure 1 and Equation 1 from the book for details. Figure 1 Equation 1 Can you point us in the right direction with the mobilization distance, x? A: Yes, please see Figure 2 for high-density polyethylene (HDPE). […]

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GMA Techline: Anchors, tie-rods and whalers

April 1st, 2021

Q: We are having issues related to obstructions in the reinforced zone of our mechanically stabilized earth (MSE) retaining walls. In the first case, there is a rock outcrop that is limiting the length of the geogrid reinforcement. In the second case, we have a drop-down inlet structure to divert stormwater, which is in the […]

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Development of a new design method for geosynthetic-reinforced RPEs

April 1st, 2021

By Pietro Rimoldi and Nicola Brusa Rapid and extreme climate change is putting our planet under stress. As a consequence, in mountain and hilly regions, infrastructure and people are more often threatened by quick and unpredictable rockfall events. Falling boulders can have extremely high speeds, exceeding 11 mph (5 m/s) and up to 67 mph […]

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A new specification for geotextile grout filled mattresses

April 1st, 2021

By George R. Koerner FIGURE 1 GGFM being filled incrementally. Courtesy of HUESKER Geotextile grout filled mattresses (GGFM), also referred to (in ASTM D18.25/D35.05) as fabric-formed concrete (FFC) or fabric-formed concrete revetments (FFCR), are erosion-resistant concrete linings made from durable, permeable fabric forms that are filled with high-strength grout. GGFMs are generally sloping structures placed […]

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Solmax liners help secure 10-day build of Wuhan hospital

April 1st, 2021

Workers involved in the installation of the Solmax liner for the Huoshenshan Hospital in Wuhan, China. Photograph courtesy of Solmax In late January 2020, just before the Chinese Lunar New Year, the COVID-19 pandemic broke out in large areas of Wuhan, Hubei Province, China. The city went into lockdown on Jan. 23, 2020, with the […]

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GMA Techline: GRI-GM19 peel specification

April 1st, 2021

Q: Our liner system is a double composite and along a western tie-in. We need to extrusion-weld the secondary 60-mil (1.5-mm) HDPE (new cell) to an existing secondary 40-mil (1-mm) HDPE (old cell), and the state is continuing to have issues with the fact that we are using the 40-mil (1-mm) GRI-GM19 peel specification as […]

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Three very different uses of geosynthetics

April 1st, 2021

In this April/May issue of Geosynthetics magazine, our feature authors tackle three very different uses of geosynthetics with in-depth examination, testing and even a new design method.  In the introduction to their article, “Modular Geosynthetics Construction,” E. Silva, T. D. Stark and Duff Simbeck discuss the benefits of a specific manufacturing process for geomembranes. They […]

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Chair’s corner and GMA happenings

April 1st, 2021

By Bryan Gee What’s in a name? For those of us who work in the geosynthetics industry, this question may be more important than you think. A recent call with a high-level federal policy maker brought this home to me. With no prior knowledge of our industry, this person did not understand what geosynthetic materials […]

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Modular geosynthetics construction

April 1st, 2021

By Edward J. Silva, T. D. Stark and Duff Simbeck Modular construction is a process in which a building or other item is constructed primarily off-site; under controlled factory conditions; and using the same design, materials, equipment, testing and construction quality control and assurance (CQC/CQA) techniques as a field-constructed facility—but usually in about one-half the […]

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