Air-channel testing of thermally bonded flexible polypropylene geomembrane seams

April 1, 2013  |  Features

By Timothy D. Stark, Richard W. Thomas, and Thomas J. Dehlinl Introduction For more than a decade, thermal welding has proven to be an efficient and cost-effective procedure for field-seaming geomembranes. Thermal welding of polyvinyl chloride (PVC) geomembranes has allowed use of air-channel tests …
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Recognizing the benefits of GRS bridge-building technology

August 1, 2012  |  Features, News

Take the leap of faith By Jessica Bies Introduction More than seven years after the Federal Highway Administration (FHWA) and local officials in Defiance County, Ohio, built their first geosynthetic-reinforced soil (GRS) integrated bridge, county engineers throughout the U.S. are starting to recogni…
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ASTM D6637–11 standard test method

November 10, 2011  |  Features

The determination of the tensile force-elongation values of geogrids provides index property values. This test method is used for quality control and acceptance testing of commercial shipments of geogrids. In cases of dispute arising from differences in reported test results when using this test met…
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ASTM D7747–11 standard test method

November 10, 2011  |  Features

The use of reinforced geomembranes as barrier materials has created a need for a standard test method to evaluate the quality of seams produced by thermo-fusion methods. This test method is used for quality control purposes and is intended to provide quality control and quality assurance personnel w…
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New ASTM geosynthetic practice standardizes leak-detection method

November 10, 2011  |  Features

A new ASTM International practice standardizes a geoelectric method used to detect potential leaks in exposed electrically isolating membranes in the field in containment applications. The new standard, ASTM D7703, Practice for Electrical Leak Location on Exposed Geomembranes Using the Water Lance S…
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Leak location

October 1, 2011  |  Features

From the GMA Techline RE: Leak location I have been reading though the GSI White Paper #8 regarding the CQA method. I am designing a reservoir that will be around 50ft deep and has many 2:1 sideslopes (uncovered 60-mil HDPE liner) that I would also need to test for leakage. It doesn’t seem tha…
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Accelerated flow testing of geosynthetic drains

June 1, 2011  |  Features

By Sam Allen Introduction Most planar geosynthetic drains consist of a polymeric core with or without a geotextile bonded to one or both sides. The core, whether used by itself or in association with a geotextile, forms the main fluid transmission medium. Synthetic cores used in North America typica…
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‘Old-timer’ recalls the history of geomembrane interface strength tests (Part 3)

June 1, 2011  |  Features

By Allan J. Breitenbach, P.E. Editor’s note: Part 1 of Allan Breitenbach’s treatise recalling geomembrane testing in days of yore appeared in the February/March issue of Geosynthetics and continued with Part 2 in the April/May issue. This concluding section continues with descriptions of…
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‘Old-timer’ recalls the history of geomembrane interface strength tests (Part 2)

April 1, 2011  |  Features

By Allan J. Breitenbach, P.E. Editor’s note: Author Breitenbach’s treatise recalling geomembrane testing in days of yore started with Part 1 in the February/March issue of Geosynthetics. He continues in Part 2 with an examination of several related factors that influenced liner interface…
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‘Old-timer’ recalls the history of geomembrane interface strength tests (Part 1)

February 1, 2011  |  Features

By Allan J. Breitenbach, P.E. Introduction I was fortunate enough to attend the interesting 9th International Conference on Geosynthetics (9ICG) in Guarujá, Brazil, in May 2010. During the last day of presentations there was a good discussion on large-scale, laboratory, direct-shear liner tes…
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