October 2009 Issue

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  Concerns regarding spark testing

  While the August/September article on subsurface biofilters was very interesting in demonstrating the wide range of geosynthetics used, I have concerns with the description of spark testing.

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  The professor training courses for geosynthetics: 1994-1998

  Fifteen years ago, the Professor Training Course for Geosynthetics began training U.S. professors to teach geosynthetics at the university level. This paper reviews how the course was conceived, funded and run, and examines the results.

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  History, development, and future prospects for geosynthetics industries in China (Part 2 of 2)

  This article presents an introduction to the development of China's geosynthetic production, applications, testing, and research, and discusses the market supply and demand as well as development trends.

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  Geo at P.S. #1

  “Afterparty,” the installation by MOS Architects at P.S.1 Contemporary Art Center in Long Island City, N.Y., opened last June to much professional acclaim.

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  Erosion control work at Pali Tunnel in Hawaii

  Geotextile reinforcement is part of an effort to stabilize a slope at the Pali Tunnel on the island of Oahu.

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  Geotextile mats are curbing threats of weed invader in Ireland

  A non-native weed is choking off some of best fishing lakes in Ireland and disturbing water supplies in the west of the country.

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  Innovative applications for nonwoven geotextiles in concrete pavements

  Recent research published by the Federal Highway Administration (FHWA), “Nonwoven Geotextile Interlayers for Separating Cementitious Pavement Layers: German Practice and U.S. Field Trials”¹ focuses on innovative applications for nonwoven geotextiles in concrete pavements.

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  Geosynthetics: Recalling the days of yore

  The history of geosynthetics has been richly documented by our scholars, researchers, writers, and manufacturers—to list but a handful of sources. Excerpts from these sources are offered here as a “look back.”

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  Floating geomembrane cover improves biogas collection, heat retention, and odor control

  Canadian corn products refiner, Casco Inc., upgraded its 4-million-gallon wastewater anaerobic digester in Ontario, Canada to include a state-of-the-art insulated, floating geomembrane cover.

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  Welding help for the Guangzhou Metro

  A major urban rail project in southeast China uses new welders to get the job done on time.

• Liner thickness

  I doubt if thickness is calculated by most engineers and they simply “go with the flow.”

• Geomembrane installations

  Let me mention that moisture in the seam area to be bonded is the most important detriment to the making of quality seams.

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  Silver anniversary: the Tanque Verde retaining walls

  Some days it seems like we have been designing and constructing concrete-faced, geosynthetic-reinforced, mechanically stabilized earth (MSE) walls forever, and that this technique of constructing MSE walls has always been a conventional solution to grade separation projects.

• Geogrid reinforcing behind rigid concrete retaining walls

  One can construct a wraparound geotextile reinforced wall to the effect that 100% of the lateral load is carried by it and zero goes to the concrete, which now acts as a facing.

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  Geocells: The early days with the Army Corps

  What many people may not know about the early development of the geocell cellular confinement system is that the material wasn’t always black.

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• Geogrid reinforcing behind rigid concrete retaining walls

  One can construct a wraparound geotextile reinforced wall to the effect that 100% of the lateral load is carried by it and zero goes to the concrete, which now acts as a facing.

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  A young engineer, molasses, and failed sand drains

  Prior to 1959, the chemical industry used sugar cane (mainly from Cuba) for its source of the carbohydrate sucrose used to produce ethyl alcohol for the manufacture of munitions and alcohol.

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  Erosion control work at Pali Tunnel in Hawaii

  Geotextile reinforcement is part of an effort to stabilize a slope at the Pali Tunnel on the island of Oahu.

• 

  Innovative applications for nonwoven geotextiles in concrete pavements

  Recent research published by the Federal Highway Administration (FHWA), “Nonwoven Geotextile Interlayers for Separating Cementitious Pavement Layers: German Practice and U.S. Field Trials”¹ focuses on innovative applications for nonwoven geotextiles in concrete pavements.

• 

  Silver anniversary: the Tanque Verde retaining walls

  Some days it seems like we have been designing and constructing concrete-faced, geosynthetic-reinforced, mechanically stabilized earth (MSE) walls forever, and that this technique of constructing MSE walls has always been a conventional solution to grade separation projects.

• 

  Welding help for the Guangzhou Metro

  A major urban rail project in southeast China uses new welders to get the job done on time.

• 

  Floating geomembrane cover improves biogas collection, heat retention, and odor control

  Canadian corn products refiner, Casco Inc., upgraded its 4-million-gallon wastewater anaerobic digester in Ontario, Canada to include a state-of-the-art insulated, floating geomembrane cover.

• 

  Geotextile mats are curbing threats of weed invader in Ireland

  A non-native weed is choking off some of best fishing lakes in Ireland and disturbing water supplies in the west of the country.

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  Show us your favorite geosynthetics photo

  We were asked to complete a leak-location survey to identify the source(s) of a leak in a PVC liner for a decorative pond.

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• Floating interface testing for direct shear

  The first test using multiple interfaces was actually conducted in the bed of a dump truck in about 1985.

• GSI/GRI-GG5 and ASTM D6706

  GRI–GG5 was the original test method on the subject but, subsequently, ASTM provided its own.

Back to Top

• Geogrid reinforcing behind rigid concrete retaining walls

  One can construct a wraparound geotextile reinforced wall to the effect that 100% of the lateral load is carried by it and zero goes to the concrete, which now acts as a facing.

• CQA test frequency for geomembranes and geocomposites

  The CQA plan on tests and their frequencies is the right and duty of the CQA organization, since they are signing off on the completed project.

• HDPE welding

  I think that many field welding technicians would love to weld at 104°F during the summer. It is really very doable, especially on a white sheet.

• Liner thickness

  I doubt if thickness is calculated by most engineers and they simply “go with the flow.”

• Geomembrane installations

  Let me mention that moisture in the seam area to be bonded is the most important detriment to the making of quality seams.

• Installing prefabricated vertical drains

  Following the information listed in Designing with Geosynthetics, 5th Edition, the statement 1-2 meters is the typical spacing for PVDs.

• GSI/GRI-GG5 and ASTM D6706

  GRI–GG5 was the original test method on the subject but, subsequently, ASTM provided its own.

• Floating interface testing for direct shear

  The first test using multiple interfaces was actually conducted in the bed of a dump truck in about 1985.

Back to Top