... to sodium bentonite via wet mixing and dry mixing. Conducting a series of HC tests on amended and unamended samples, polymer retention and elution were assessed using thermogravimetric and total organic carbon analyses. NaCMC incorporation under dry mixing reduced the HC by approximately 60%. The dry-mixed...

...A. Norris; J. Scalia IV; C. D. Shackelford The hydraulic conductivity (k) of specimens of enhanced-bentonite geosynthetic clay liners (EB-GCLs) comprising anionic polymers permeated with two concentrated salt solutions, 500 mM NaCl and 167 mM CaCl₂, was measured to determine...

... 2020 06 03 2020 © 2020 Thomas Telford Ltd 2020 Geosynthetics GCL Water retention curve Wetting path Bentonite Composite liner systems are frequently used in waste containment facilities to mitigate soil and groundwater contamination (Bouazza and Bowders 2009 ; Rowe 2012...

..., and the hydraulic conductivity of a GCL specimen are almost reversible when it is subjected to an osmotic cycle. 24 05 2019 24 09 2019 14 12 2019 © 2020 Thomas Telford Ltd 2020 Geosynthetics Geosynthetic clay liners Consolidation Bentonite Salinity For the osmotic...

...Y. Liu; W. P. Gates; A. Bouazza This study reports supportive evidence, from scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (TEM) of bentonite cakes, of the textural effects caused by reaction of concentrated sulfuric acid on the bentonite component...

...J. Scalia, IV; G. L. Bohnhoff; C. D. Shackelford; C. H. Benson; K. M. Sample-Lord; M. A. Malusis; W. J. Likos The sensitivity of sodium bentonite (Na-B) to adverse chemical interactions has spurred development of enhanced bentonites (EBs) for geosynthetic clay liners (GCLs) that provide superior...

...G. Di Emidio; F. Mazzieri; R.-D. Verastegui-Flores; W. Van Impe; A. Bezuijen ABSTRACT: The purpose of hydraulic barriers, such as geosynthetic clay liners (GCLs), is to isolate waste liquids from the environment. Bentonite clay is widely used in GCLs because of its elevated sealing capacity...

... the interface between the geomembrane and GCL resulting in the formation and flow of condensed moisture beneath the geomembrane. All four of the GCL products investigated at the Queen's University Environmental Liner Test Site were shown to have experienced significant bentonite erosion after 4.7 years...

..., improvements for GCL strength testing are suggested, and future research needs are identified. 11 11 2014 21 11 2014 21 11 2014 © 2015 Thomas Telford Ltd 2015 geosynthetics geosynthetic clay liner bentonite shear strength durability shear test stability analysis landfill...

...M. Ahari; N. Touze-Foltz; L. Mazéas; A. Guenne ABSTRACT: The aim of this paper is to present the experimental results obtained regarding the adsorption on various constitutive geotextiles and bentonites of geosynthetic clay liners of phenol, o-cresol, p-cresol, 2-chlorophenol, 4...

... limits the risk of moisture distribution change in the bentonite, which has been observed under high pressure gradients. However, a consequence of a low pressure gradient is a small gas flow rate that is difficult to measure with good accuracy. Therefore a solution may be the use of transient state tests...

...J. Frankovská; S. Andrejkovičová; I. Janotka ABSTRACT: Sodium bentonite (Na-bentonite) is used as a sealing component in geosynthetic clay liners (GCL). Na-bentonite is very sensitive to chlorides, and flocculation occurs when it is exposed to saline environments. The purpose of this work...

... when the mass per unit area was evenly distributed. However, specimens with an uneven bentonite distribution (typically those with a low mass per unit area) can have areas of little to no bentonite content, and these specimens experienced much higher shrinkage than other specimens. A high degree...

... or needle-punched) and different bentonites (natural sodium or natural calcium) were tested. The results obtained showed no significant differences among flow rate versus time in most of the tests performed, especially after the steady-state conditions of flow were reached. An analytical solution...

...S. Rosin-Paumier; N. Touze-Foltz; A. Pantet; P. Monnet; G. Didier; D. Guyonnet; V. Norotte ABSTRACT: Geosynthetic clay liners (GCLs) are used in landfill liner applications and there is a need for a better control of the properties of the bentonite in the GCL received on site, particularly...

... of other more common inorganic ions such as Ca, Na, S (SO₄) and Cl are also considered, as well as the impact of pH, Eh and speciation on metal mobility in GCLs. Geosynthetics Geosynthetic clay liners (GCL) Metals Bentonite Diffusion Sorption Tailings Concerns related to metal...

... of metal per gram of bentonite (ppm), and are indicative of the GCL's sorption capacity for a barrier system. Significant differences existed between the soil tested at 2 PV 5 PV and 21 PV It was only at 5 PV that the precipitation of the ferrihydrite occurred in the ARD samples, and gypsum occurred...

...J. P. Giroud; D. E. Daniel In some applications of geosynthetic clay liners (GCLs), the bentonite layer component of the GCL is encapsulated between two geomembranes. One of the benefits of this configuration is to decrease the risk of shear strength decrease due to bentonite hydration. The liner...

...J. P. Giroud; R. S. Thiel; E. Kavazanjian Hydrated bentonite has a low shear strength, which may adversely impact the stability of structures incorporating geosynthetic clay liners (GCLs). Accordingly, in a growing number of GCL applications, the configuration is such that the bentonite layer...

... bentonite placed against a smooth geomembrane to measure the drained, residual strength of this interface. The use of thin specimens minimizes the time required to achieve drained conditions, and also minimizes the shear displacement required to mobilize the residual strength; testing times were several...