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Showing 1 to 13 of 13 for “"Geomembranes"”.
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Long-Term Performance of HDPE Geomembranes as Landfill Liners
High density polyethylene (HDPE) geomembranes are normally used as part of a composite liner for waste containment facilities such as municipal solid waste (MSW) landfills and heap leach pads. Field conditions, which include physical stresses on the geomembrane, elevated operating temperatures, and …
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Physical Performance of Geomembranes Used in Heap Leach Pad Applications
Geomembranes (GMB) are normally used as part of the liner system in heap leach pads. There is a need to quantify tensile strains in the geomembrane that could affect short-term puncture and long-term performance of the GMB. In this thesis, short-term tensile strains arising from indentations caused …
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Calculating and Limiting Local Strains in Geomembranes From Gravel Indentations
Short-term tensile strains that arise from local gravel indentations in municipal solid waste landfill base geomembrane liners are investigated with an emphasis on quantifying how strains are obtained and providing methods for limiting long-term local geomembrane strains below allowable levels. …
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Ageing of HDPE Geomembranes Used to Contain Landfill Leachate or Hydrocarbon Spills
The ageing of high density polyethylene geomembrane (GM) liners used to minimize advection and diffusion of contaminants in municipal solid waste landfill leachate and in hydrocarbon spills to the environment is examined. The evaluation of the ageing of GMs used in landfills involved four …
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The Chemical Durability of Elastomeric Bituminous Geomembranes (BGMS) in Different Geoenvironmental Applications at Elevated Temperatures
The chemical durability of elastomeric bituminous geomembranes (BGMs) is investigated using laboratory accelerated immersion tests for different geoenvironmental applications. The effects of elevated temperatures, thickness, and incubation media on the mechanical, rheological, and chemical …
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Comparison of shear strength properties of textured polyethylene geomembrane interfaces in landfill liner systems
The interface shear strength between geomembranes and geosynthetics is a critical factor governing the stability of slopes that incorporate geosynthetics. In order to better characterise the shear properties of geomembranes, a wide-range of shear strength friction measurements were conducted. This …
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Containment of Organic Contaminants Using Geosynthetics
… and xylenes (BTEX) and PCBs through geomembranes are evaluated. Diffusion of BTEX is also evaluated through vapour barriers, as well as diffusion of PCBs through a compacted clay liner (CCL) and a GCL. The permeation coefficient (Pg) for BTEX diffusion was lowest for high density …
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An Investigation into the Effects of Asperities on Geomembrane/Geotextile Interface Shear Characteristics
Geomembranes are often utilized as fluid barriers in geotechnical applications such as landfills. Due to their relative impermeability and chemical resistance characteristics, they are usually used alongside other geosynthetics like geotextiles in landfills to constitute base, side-slope, and cover …
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Modeling contaminant transport in polyethylene and metal speciation in saliva
… and aged polyethylene materials for pipes and geomembranes. Diffusivity, solubility, polymer and chemical properties were measured for thirteen contaminants and six polyethylene materials that were new and/or aged in chlorinated water. Tree regression was used to select variables, and linear …
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Field Performance of Exposed Geosynthetic Composite Liner Systems
… and high albedo white high-density polyethylene geomembranes (both smooth and textured). Relative to the black geomembrane, wrinkles in the white geomembrane formed later in the morning and reduced sooner in the evening. Wrinkles in the white geomembrane relative to the black were less frequent, …
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Comparative Assessment of Single & Double Interface Shear Strength Properties: A Case Study of a Landfill Project in the Western Cape Province, South Africa
… three nonwoven geotextiles, two smooth-sided geomembranes, a synthetic cuspate drain, sand, gravelly sand (GS), and leachate collection stone (LCS). All tests were conducted at applied normal pressures of 150, 300, & 450 kPa under saturated conditions with fresh tap water at a 1mm/min shearing …
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Field-Scale Monitoring and Laboratory Simulation of Geosynthetic Liners During Construction and After Placement of Waste
Two physical issues of geomembrane wrinkle deformations and downslope shear deformations – that need to be considered to obtain good long-term geomembrane liner performance – are examined. First, field-scale monitoring of geomembrane wrinkles in a 1.5-mm-thick, black high-density polyethylene …
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Dimensional Stability of Geosynthetic Clay Liners in Landfill Applications
… 3 wet-dry cycles. GCL specimens without attached geomembranes contracted beyond the PST in the XMD within 5 cycles. Permeant type tests demonstrated that hydration with 0.1 M CaCl<sub>2</sub> reduced shrinkage by 50-80% compared to permeation with tap water. Overburden tests demonstrated that …