Extrusion welds

October 1st, 2011

GMA techline answers from Bob Koerner RE: Welds Are destructs typically conducted on extrusion welds? Our flexible membrane liner (FML) spec doesn’t specifically address this. It does explicitly list a destruct frequency of every 500 linear feet of seam length. Does “seam” refer to both extrusion and fusion welds, or just fusion? Should we track […]

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Draping and spraying

October 1st, 2011

From the GMA Techline RE: Draping and spraying I am looking for a geosynthetic fabric webbing or netting that can be draped and then sprayed with concrete. (Ted | California) Reply: I suspect you are talking about shotcrete of gunite and my answer is accordingly. Fabric-wise, you are probably best with a needle-punched nonwoven since […]

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Pond liner

October 1st, 2011

From the GMA Techline RE: Pond liner We have some air pockets under the geomembrane as the pond fills with water. Rather than try to cut and patch the flexible membrane liner (FML), would it not be easier to simply leave the anchor trench unfilled in those areas to “burp” the air out up top […]

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Leak location

October 1st, 2011

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 that the […]

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Comparing GCLs

October 1st, 2011

From the GMA Techline RE: GCLs I need some assistance in comparing two geosynthetic clay liners for a project where the specification gives a total bentonite mass required of 4500g/m2 and a target hydraulic conductivity of < 5 × 10-11. We have an option of a liner that far exceeds the requirement of the hydraulic […]

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Liner questions

October 1st, 2011

From the GMA Techline RE: Liner questions I am designing a surface impoundment with interior side slopes of 1.5H:1V. This impoundment requires (per regulations) a geosynthetic clay liner (Bentomat DN or equivalent), 40-mil HDPE secondary liner, and 60-mil HDPE primary liner. A leak-detection system has been requested. The pit is small (approximately 500ft x 200ft) […]

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Reduced CO2 emissions and energy consumption with geosynthetic installations

October 1st, 2011

From the Geosynthetics Research Institute’s 24th conference, 2011.The articles in this series encompass all types of geosynthetics and their applications viewed from the context of sustainability. Traditional solutions are compared with geosynthetic solutions from both cost and carbon footprint perspectives. (from the Geosynthetic Research Institute’s 24th conference, 2011) Abstract In April 2010, GSE released a […]

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On the waterfront

October 1st, 2011

A plan to rework the Don River Park near downtown Toronto uses geotextile-wrapped wick drains to remediate soil and drainage problems By Adam Regn Arvidson A new neighborhood is growing on 80 acres (32 hectares) of former industrial land near downtown Toronto. Called the West Don Lands, it will be home to 6,000 housing units, […]

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Emergency water supply: The Upper Chiquita Reservoir

October 1st, 2011

By Steve Roades Introduction The recently completed Upper Chiquita Reservoir in Southern California was built to provide the region with substantial new water reserves to meet customer demand during disruptions of water deliveries. These interruptions can be unanticipated—for example, the 1999 break in a primary supply pipeline—or planned, such as a shutdown of the filtration […]

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The role of geosynthetics in the new New Orleans levees

October 1st, 2011

By Angelle Bergeron Introduction Geosynthetic materials are playing a critical role in providing New Orleans with its best flood protections ever. “We couldn’t have delivered this work by 2011 without geosynthetics,” said Richard Varuso, deputy chief of the geotechnical branch of the U.S. Army Corps of Engineers’ New Orleans District (USACE/NOD). “Geosynthetics save construction time.” […]

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