Geosynthetics for marine structures

April 1, 2024  |  Q&A: GMA Techline

Q: Are geosynthetics allowed to be used in marine structures? I am concerned about plastics in the environment and emission of plastic additives and their degradation by-products. 
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Geotextile quality issues

April 1, 2024  |  Q&A: GMA Techline

Q: We are performing certified quality auditing (CQA) at a jobsite and having major quality issues with the geotextile delivered to the site. For example, the mass per unit area is low, all mechanical properties are below specification, the permittivity and apparent opening size (AOS) are low. We ar…
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Temporary interim covers

April 1, 2024  |  Q&A: GMA Techline

Q: I am writing to inquire if you are aware of any recommendations or guidelines for removal of geosynthetic liners that have been used as temporary interim covers at landfills. We recommend facilities totally take up and remove the temporary cover; however, we have had some recent proposals to run …
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Geomembrane testing

April 1, 2024  |  Q&A: GMA Techline

Q: We are a geomembrane manufacturer and have a client who asked us to test an old geomembrane that we sold to them 20 years ago for a surface impoundment. They are also asking us to test a competitor’s geomembrane used at the same site. Can we issue a formal report to a governing agency of result…
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Bentonite Cutoff Anchorage

February 1, 2024  |  Q&A: GMA Techline

Q: I have a bentonite cutoff wall containing a positive pressure inside and an overfill situation where the waste being capped will have perched water in the waste mass above the perimeter elevation. Do you have a recommendation for the perimeter connection detail for such a situation?
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Geomembrane formulation

February 1, 2024  |  Q&A: GMA Techline

Q: We are specifying HDPE geomembrane for a critical project and noticed that GRI-GM13 only requires endurance testing “per formulation.” What is the definition of formulation and can we obtain Kiwa certification for a geomembrane produced using a known formulation?
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Global/Slope Stability Analysis

February 1, 2024  |  Q&A: GMA Techline

Q: My question stems from the fact that (in my area) there still seems to be confusion over when a global/slope stability analysis is required and who is responsible. A contractor might ask for some budget pricing for retaining wall design. Generally, this is in regards to a segmental retaining wall…
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Resin Sampling

February 1, 2024  |  Q&A: GMA Techline

Q: Is there a standard definition of a “lot of resin.” 
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Ply-Adhesion Values For Triplanar Geocomposites

February 1, 2024  |  Q&A: GMA Techline

Q: Is there a minimum ply-adhesion value for a triplanar geocomposite? I ask this knowing that GRI-GN4  (Test Methods, Required Properties and Testing Frequency for Biplanar Geonets and Biplanar Geonet Composites) specification states a minimum of 1.0 pound/inch. 
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Drainage Geocomposite Applications

February 1, 2024  |  Q&A: GMA Techline

Q: Do you have any case history information where a geocomposite was used as an underdrain below flat-plate, upstream armoring on an embankment dam? Specifically, I am looking for any long-term performance information (good or bad) and how much of that system (if any) may have had to be replaced due…
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