Impregnation of GCLs

April 1st, 2022

Q: We are confused with the term “impregnation” as it relates to seaming geosynthetic clay liners (GCLs). There are two types of impregnations: (1) Edge impregnation, and (2) complete nonwoven (cap layer) impregnation of GCLs. How does a manufacturer do this? A: The edge impregnation of GCLs (1) is done in the field by an […]

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GCL-GM geocomposite: Which end is up?

April 1st, 2022

Q: In a geosynthetic clay liner-geomembrane (GCL-GM) geocomposite, does it make any difference which side of the geocomposite is up: GM or clay? A: This is a very detailed question that is application specific. The following design details all need to be considered: Is the GCL-GM geocomposite used for a liner or a cover, is […]

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Calendared nonwoven geotextiles

April 1st, 2022

Q: What is the difference between normal nonwoven and calendared nonwoven (both needlepunched) geotextiles? Where can we use calendared nonwoven geotextiles? A: Calendared nonwoven geotextiles are passed between a set of heated rollers that applies normal pressure as a tertiary process of the production. This process increases the modulus, strength, tear resistance, puncture resistance and […]

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LCC curing effect on geogrids

April 1st, 2022

Q: Can you tell me whether modest warming of geogrids (e.g., due to heat generated by the curing of lightweight cellular concrete [LCC]) might impact the long-term strength or long-term modulus of geogrids? A: You need to know the maximum temperature due to the heat from hydration of the LCC. Most pozzolanic reaction temperatures (like […]

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High pH effects geogrids?

April 1st, 2022

Q: Can you tell me whether the high pH of curing portland cement (typically ~12.4) might have any impact on the long-term performance of geogrids? A: It depends on the geogrid and its formulation. There are three categories of geogrid: (1) punched and drawn (polyethylene [PE] uniaxial, polypropylene [PP] biaxial and triaxial), (2) strap (polyvinyl […]

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GSI agriculture/aquaculture webinar upcoming

February 25th, 2022

GSI agriculture/aquaculture webinar on March 16, 2022, will focus on geosynthetics in farming and fish farming operations. A Raven Engineered Films geosynthetic agricultural silage cover. The upcoming GSI agriculture/aquaculture webinar will include such uses. Photograph courtesy of Raven Engineered Films The Geosynthetic Institute (GSI) will sponsor a webinar, “Geosynthetics in Agriculture and Aquaculture,” on March […]

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Reinforced levees to induce seepage path around geogrid layers?

February 1st, 2022

FIGURE 1 Reinforced levee expansion over existing dike using geosynthetics The Geosynthetic Institute (GSI) has been asked many times regarding several applications for different styles of geogrids if reinforced levees will induce a seepage path adjacent to and around geosynthetic layers. At this point, GSI has no case histories where it can quantify such behavior […]

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GSI to host webinar on geosynthetics in heap leach mining

January 27th, 2022

Photograph courtesy of NAUE GmbH & Co. KG The Geosynthetic Institute (GSI) will sponsor a webinar, “Geosynthetic Applications Used in Heap Leach Mining,” on Feb. 9, 2022, from 11:30 a.m. to 1 p.m. EST. Geosynthetic Materials Association (GMA) member companies and their employees receive discounted rates on all GSI webinar and short course registrations. The […]

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GSI to host webinar on geosynthetics in hydraulic applications

December 23rd, 2021

A 30-mil (0.8-mm) polyvinyl chloride (PVC) geomembrane with a 10-ounces-per-square-yard (339-g/m2) nonwoven geotextile cushion is installed for a stormwater/erosion control project in Harrisburg, Pa. Photograph courtesy of ACF Environmental The Geosynthetic Institute (GSI) will sponsor a webinar, “Geomembranes in Hydraulic Applications (dams, canals, reservoirs, tunnels, pipes),” on Jan. 12, 2022, from 11:30 a.m. to 1 […]

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GSI to host webinar on disposal of coal combustion residuals

November 26th, 2021

Photograph courtesy of Solmax The Geosynthetic Institute (GSI) will sponsor a webinar, “Disposal of Coal Combustion Residuals,” on Dec. 8, from 11:30 a.m. to 1 p.m. EST. Geosynthetic Materials Association (GMA) member companies and their employees receive discounted rates on all GSI webinar and short course registrations. With coal representing more than 25% of energy […]

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