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Double Liner
A double liner is a fluid barrier system that incorporates two impermeable layers separated by a permeable drainage layer also called a leak detection layer. Typically the impermeable layers are made from geomembranes with a permeable layer in between. The uppermost layer is called the primary liner while the lower layer is called the secondary liner.https://www.nrc.gov/docs/ML1821/ML18215A331.pdf This combination of layers is designed to prevent hydraulic head from building on the secondary liner, thereby limiting or preventing any permeation into the secondary liner. Due to the difficulty of constructing a single large scale impermeable layer without any defects, a double liner system is more robust, as it can deal with leakage through the primary liner. A double liner system is required by the United States EPA for landfill, surface impoundments, and waste piles. History The first double geomembrane liner system was designed by geosynthetics pioneer J.P. Giroud, and installed in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geomembranes
A geomembrane is very low permeability (earth sciences), permeability synthetic membrane liner or barrier used with any geotechnical engineering related material so as to control fluid (liquid or gas) migration in a human-made project, structure, or system. Geomembranes are made from relatively thin continuous polymeric sheets, but they can also be made from the impregnation of geotextiles with Bitumen, asphalt, elastomer or polymer, polymer sprays, or as Bituminous Geomembranes (BGMs), multilayered bitumen geocomposites. Continuous polymer sheet geomembranes are, by far, the most common. Manufacturing The manufacturing of geomembranes begins with the production of the raw materials, which include the polymer resin, and various additives such as antioxidants, plasticizers, fillers, carbon black, and lubricants (as a processing aid). These raw materials (i.e., the "formulation") are then processed into sheets of various widths and thickness by extrusion, calendering, and/or spread ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Head
Hydraulic head or piezometric head is a measurement related to liquid pressure (normalized by specific weight) and the liquid elevation above a vertical datum., 410 pages. See pp. 43–44., 650 pages. See p. 22, eq.3.2a. It is usually measured as an equivalent liquid surface elevation, expressed in units of length, at the entrance (or bottom) of a piezometer. In an aquifer, it can be calculated from the depth to water in a piezometric well (a specialized water well), and given information of the piezometer's elevation and screen depth. Hydraulic head can similarly be measured in a column of water using a standpipe piezometer by measuring the height of the water surface in the tube relative to a common datum. The hydraulic head can be used to determine a ''hydraulic gradient'' between two or more points. Definition In fluid dynamics, the ''head'' at some point in an incompressible (constant density) flow is equal to the height of a static column of fluid whose pressure at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean-Pierre Giroud
Jean-Pierre Giroud (born March 13, 1938) is a French geotechnical engineer and a pioneer of geosynthetics since 1970. In 1977, he coined the words "geotextile" and "geomembrane", thus initiating the "geo-terminology". He is also a past president of the International Geosynthetics Society, member of the US National Academies, and Chevalier de la Légion d'Honneur. Education and career Giroud is a civil engineer from Ecole Centrale de Paris, and he got his Ph.D. in geotechnical engineering at the University of Grenoble The (, ''Grenoble Alps University'', abbr. UGA) is a Grands établissements, ''grand établissement'' in Grenoble, France. Founded in 1339, it is the third largest university in France with about 60,000 students and over 3,000 researchers. Es .... He has been president of the International Geosynthetics Society (1986–1990) and director of the Geotextiles and Geomembranes Group of Woodward Consultants (1978–1983). He was the co-founder and chairman of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Le Pont-de-Claix
Le Pont-de-Claix (, literally ''The Bridge of Claix''; ) is a commune in the Isère department in southeastern France. It is part of the Grenoble urban unit (agglomeration). INSEE Population International relations Le Pont-de-Claix is twinned with: * Winsen, GermanySee also *Communes of the Isère department
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Bituminous Geomembranes (BGMs)
Bituminous geomembrane (BGM) is a type of geomembrane consisting of a reinforcing geotextile to provide mechanical strength and elastomeric bitumen (often called asphalt in American English, U.S.) to provide impermeability. Other components such as sand, a glass fleece, and/or a polyester film can be incorporated into the layers of a BGM. Bituminous geomembranes are differentiated from bituminous waterproofing materials used in buildings due in part to their wide roll width, which can exceed 5m, and their substantial thickness of up to 6.0mm. These properties are designed for environmental protection, civil infrastructure, and mining applications. Properties History The earliest estimated use of bitumen dates back 40,000 years to the Paleolithic age and bitumen#History, the historical use of bitumen as a waterproofing layer is extensive and well documented. In 1926, successful experiments were conducted by the South Carolina Highway Department in which cotton fabric wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butyl Rubber
Butyl rubber, sometimes just called butyl, is a synthetic rubber, a copolymer of isobutylene with isoprene. The abbreviation IIR stands for isobutylene isoprene rubber. Polyisobutylene, also known as "PIB" or polyisobutene, (C4H8)n, is the homopolymer of isobutylene, or 2-methyl-1-propene, on which butyl rubber is based. Butyl rubber is produced by polymerization of about 98% of isobutylene with about 2% of isoprene. Structurally, polyisobutylene resembles polypropylene, but has two methyl groups substituted on every other carbon atom, rather than one. Polyisobutylene is a colorless to light yellow viscoelastic material. It is generally odorless and tasteless, though it may exhibit a slight characteristic odor. Properties Butyl rubber has excellent impermeability to gas diffusion, and the long polyisobutylene segments of its polymer chains give it good flex properties. The formula for PIB is: –(–CH2–C(CH3)2–)n– The formula for IIR is: It can be made from the monomer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geosynthetics
Geosynthetics are synthetic products used to stabilize terrain. They are generally polymeric products used to solve civil engineering problems. This includes eight main product categories: geotextiles, geogrids, geonets, geomembranes, geosynthetic clay liners, geofoam, geocells and geocomposites. The polymeric nature of the products makes them suitable for use in the ground where high levels of durability are required. They can also be used in exposed applications. Geosynthetics are available in a wide range of forms and materials. These products have a wide range of applications and are currently used in many civil, geotechnical, transportation, geoenvironmental, hydraulic, and private development applications including roads, airfields, railroads, embankments, retaining structures, reservoirs, canals, dams, erosion control, sediment control, landfill liners, landfill covers, mining, aquaculture and agriculture. History Inclusions of different sorts mixed with soil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
