The ASTM D1505 Method

June 1, 2023  |  Q&A: GMA Techline

Q: I want to measure the density of a mineral-filled composite polymer mixture by the ASTM D1505 method. What liquid will be used for density measurement (density >1)? The products to be tested are made of either polypropylene or polyethylene with calcium carbonate and additives. We will be addin…
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Geomembrane welding below freezing

June 1, 2023  |  Q&A: GMA Techline

Q: Can geomembrane welding be done below freezing (32 degrees Fahrenheit [0 degree Celsius])? If it can be done, is there a method or preferred procedure to assure its success?
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Understanding Geomembrane Asperity

April 1, 2023  |  Q&A: GMA Techline

Q: Twice in the past few weeks colleagues asked me the same question about geomembrane asperity, so I come to you to understand it. 
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Strip or Sheet Drain Vs. French Drain

April 1, 2023  |  Q&A: GMA Techline

Q: What are benefits to using “strip or sheet drain” over conventional French drain construction with soils?
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Geosynthetics for Precipitate Clogging

April 1, 2023  |  Q&A: GMA Techline

Q: We are retrofitting a highway edge drain where rubberized concrete was used as the base course layer. What type of geotextile or geosynthetic should we consider for this project’s drain?
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Dewatering Bags for Erosion and Sediment Control

April 1, 2023  |  Q&A: GMA Techline

Q: How does a dewatering bag (Dirt Bag, sediment container, Siltsack, etc.) work on a construction site to help you with your erosion and sediment control plan?
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Landfill Gas Emissions Modeling

February 1, 2023  |  Q&A: GMA Techline

Q: I’m writing to see if you are aware of any research on landfill gas (LFG) emissions modeling through various geomembranes, particularly for temporary covers? 
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Overlap seam specifications for geotextile separators

February 1, 2023  |  Q&A: GMA Techline

Q:What is the typical overlap for a geotextile used as a separator in a highway project?
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Transitioning from 30 MIL PVC geomembrane to 60 MIL HDPE

February 1, 2023  |  Q&A: GMA Techline

Q:I have a client that operates a Subtitle C landfill that utilizes a double-liner system of 30 mil (0.76mm) PVC geomembrane for the base liner. They are wanting to evaluate the possibility to transition from 30 mil (0.76 mm) PVC to 60 mil (1.52 mm) high-density polyethylene (HDPE) geomembrane for t…
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Strength Reduction Of Geogrids Used In Reinforced Walls

February 1, 2023  |  Q&A: GMA Techline

Q:At the moment there are two issues that create uncertainty with the use of PET fabrics and geogrids in the Netherlands. First, for many years we built pile-supported geosynthetic reinforced embankments (so-called piled mattresses to reduce settlements under embankments on soft soils). The fill is …
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