Teaching geosynthetics

October 1, 2008  |  Q&A: GMA Techline

From the GMA Techline Subject: Teaching geosynthetics— I am wondering if you have a list of universities that teach at least one full-time course in geosynthetics. Thank you. (Craig, Pennsylvania) Reply: You have come to the right place! As the author of the only textbook on geosynthetics, I k…
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GMA Techline’s first 500 Q’s-and-A’s

August 1, 2008  |  Q&A: GMA Techline

By Bob Koerner and Andrew Aho Introduction The Geosynthetic Materials Association (GMA) introduced the GMA Techline on Aug. 31, 2004, as a service to those involved with, and interested in, geosynthetics. The Techline is one of the educational services offered by GMA, with the goal of providing fast…
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GRI Standards

April 1, 2008  |  News, Q&A: GMA Techline

From the GMA Techline Subject: GRI Standards — I am seeing references to GRI Standards GM 10, GM 14, and GM 18 in a project spec for a facility that will be under construction soon. There are other references too, of course, but these I’ve listed are not current, according to your Web si…
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Slack calculations

April 1, 2008  |  News, Q&A: GMA Techline

From the GMA Techline Subject: Slack calculations — Do you have a reference that discusses the impact of environmental conditions and the procedures for determining “slack” into an HDPE liner at the time of installation? (Rod, California) Reply: The subject of calculating slack in …
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Access roads on HDPE liners

October 1, 2007  |  Q&A: GMA Techline

GMA techline answers from Bob Koerner Subject: Access roads on HDPE liners— I am designing a temporary waste storage facility that will be lined with a 1.5mm HDPE liner. The facility requires access roads for the life of the facility—18 months. The access roads will be installed directly…
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HDPE welds

October 1, 2007  |  Q&A: GMA Techline

From the GMA Techline Subject: HDPE welds— For HDPE geomembranes, I am looking for information on what effect there might be, if any, on the integrity of a fusion weld when an extrusion weld is placed directly on top of it. This condition exists when completing patches at T-intersections, but …
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Product specification

June 1, 2007  |  News, Q&A: GMA Techline

From the GMA Techline Subject: Product specification We are proposing to stabilize a section of eroded riverbank with riprap. We would like to install a fabric beneath the riprap to hold the existing sandy soils in place. Can you give us a recommendation? The river is tidal and the area is exposed t…
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Geotube questions

April 1, 2006  |  Q&A: GMA Techline

From the GMA Techline Subject: GeotubeI refer to the article “Saving Yucatan’s Coast” published in the September 2005 issue of GFR (now Geosynthetics), pages 34-39. Can you please let me know the following: What mathematical calculation was used to derive the appropriate ground lev…
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Measuring puncture resistance

January 1, 1970  |  Q&A: GMA Techline

From the GMA Techline RE: Measuring puncture resistance How can I measure hydrostatic puncture resistance of a geomembrane in the field with different conditions (with or without geotextile)? [My company] uses geomembrane in agricultural pools. (Elham) Reply: The test you are looking for is ASTM D57…
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