• Proceedings of the Korean Geotechical Society Conference
• /
• 1994.03a
• /
• pp.65-74
• /
• 1994

In this paper, various aspects of landfill liners such as guide of liner installation, type of bottom liners and vertical barriers, domestic companies producing and dealing liners, quality assurance and control of liners, are investigated. Although sanitary landfilling of domestic municipal wates has begun at the last decade, we still need to strengthen the regulation for designing and constructing the liner systems and to diversify the types of liners used in the landfills. Technologies of quality control for selecting and installing landfill liners should be improved as soon as possible. In order to develop the technologies and to slove th problems related to landfill liners, more efforts should be taken among the engineers and the agencies who are interested in maintraining safe subsurface environments.

• Journal of Korea Soil Environment Society
• /
• v.1 no.1
• /
• pp.103-109
• /
• 1996

The cover liners at municipal and hazardous waste landfill is not emphasized as much as the bottom liners. However, one of the most effective reason of landfill destroy is the cover liner failure. The cover system at municipal and hazardous waste landfill, 1 perform the following functions, at minimum: promote surface runoff, impede infiltration, protect settlement in the landfill, and provide a buffer from surface exposure of the waste. This research was to expand the existing knowledge base of landfill cover liner behavior during period of freeze/thaw Also, the great Lysimeter was built in the laboratory to provide as much as same condition with the field and three designs were simulated by actual cover materials. The result of simulation indicated the clay was effected by freezing/thawing. The degradation of cover liners in the frost penetration affects the physical, engineering properties of clay. these factors may consider to design and construct of the landfill. This paper provides the description of testing cover liners, experimental results and a discussion of the results of the simulation.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.03a
• /
• pp.295-304
• /
• 2010

Performance of a landfill liner is evaluated based on leakage rate and mass flux. In this study, the recently utilized double composite liner system, which consists of a geomembrane (GM), a geosynthetic clay liner (GCL), a GM, and a compacted clay layer (61 or 91.5 cm) is compared with other popular composite liners including the single GCL system, the Subtitle D liner system, and the Wisconsin NR500 liner system. The leakage rate through circular and long defects in the GM of the landfill liners is analyzed using numerical models. For the mass flux criterion, the analyses of inorganic contaminant transport through defects in the GM component of liner systems and diffusion of organic compounds through intact landfill liners are conducted using three- and one-dimensional numerical models, respectively. Cadmium and toluene are used in the analyses as a typical inorganic and organic substance, respectively, which will be chemical species encountered during landfill operation. The comparison shows that the double composite liner systems are superior to the other liner systems according to the performance-based evaluation.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2009.03a
• /
• pp.245-254
• /
• 2009

Efficiency of landfill liners system is usually evaluated based on leakage rate and mass flux. In this study, composite liner systems including the GCL(geosynthetic clay liner) composite liner, the Subtitle D liner, the Wisconsin NR500 liner, and the recently utilized double composite liner, which is a combination of the GCL composite liner and Subtitle D-type liner, have been examined. The leakage rate through circular and long defects in the geomembrane (GM) of the liner system was analyzed with the aids of analytical and numerical methods. For the mass flux criterion, contaminant transport through defects in the GM of landfill liners can be evaluated based on the calculated leakage rates. The diffusion rate of volatile organic compounds through intact landfill liners was evaluated by performing a one-dimensional numerical model. Cadmium and toluene were adoptted in the analyses as typical inorganic and organic substances, respectively, which will be chemical species encountered during landfill operation. The performance-based evaluation indicates that the double composite liner systems are superior to the other types of liner.

• Journal of Soil and Groundwater Environment
• /
• v.7 no.1
• /
• pp.41-51
• /
• 2002

Recently, domestic waste landfills are constructed sometimes on seashore area to provide large landfill area. In order to strengthen the foundation of landfills and to prevent the infiltration of leachate through the bottom, many cases of constructing cement hardened liners on seashore clays are found. In these cases, it is possible to have cracks in the hardened liners due to settlement with waste load since the stiffness of the hardened liner Is greater than that of clay liners. In this study, the capability of Self-Sealing and Self-Healing (SSSH) liner made with a seashore clay in the metropolitan landfill to prevent the percolation of water and leachate is examined using flexible-wall permeameter test and using uniaxial compression test. Applicability of SSSH to weathered granitic soil is also examined for self-sealing capabilities. The result of Flexible permeameter test for SSSH with the seashore clay showed that permeability obtained was lower than permeability criteria of Korean waste management law. The permeability and strength characteristics of SSSH with granitic soil and bentonite showed better results than with the seashore clay.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2000.05a
• /
• pp.141-144
• /
• 2000

The slope stability of waste landfill has been a problem in domestic and foreign countries. Waste landfills are being constructed in a reclaimed land or mountainous area. But most of these places are consisted of steep slope and hence it is necessary to use the geosynthetic liners in there. The large size direct shear test(30cm x 30cm) equipment was used to determine the interface friction angles between CCLs and soil & geomembranes. The centrifuge model tests were performed to investigate the slope stability with considering various geosynthetic liners conditions and degree of slope. The results of centrifuge model test indicate that the degree of saturation of GCL, roughness of geomembrane, and slope of landfill have greatly influenced on the slope stability of solid waste landfill.

• Advances in materials Research
• /
• v.13 no.1
• /
• pp.19-35
• /
• 2024

Presented Article evaluates the effect of nanoclay on permeability, compressive strength, and plasticity behavior of fine-grained soil related to the Tabriz landfill site. In this regard, comprehensive experimental study was performed on taken soil samples (42 specimens) with aim of design high-performance liners for Tabriz landfill. The samples was mixed by 0% (control) 3%, 6% and 9% nanoclay and prepared in 1, 7, 14 and 28 days before testing stage. Index tests like particle-size, permeability, atterberg limits, and uniaxial compressive strength (UCS) was conducted on samples. The results show that studied soil is classified as CL in USCS classification and atterberg limits measured as LL is 37, PL is 20.67, and PI is 16.33 which increase into 75, 45, and 30. The assessment presented the LL was increased about 20.27% based on increasing in nanoclay from 0% to 9%. These variations for PL and PI were 21.77% and 18.37%, respectively. Also, the and soil's compressive strength is increase from 120 kPa to 188 kPa and permeability is estimated as 4.25×10^-6 m/s which reduced into the 6.34×10^-9 m/s with respect the naboclay content increases form 0% to 9%.

• Proceedings of the Korean Geotechical Society Conference
• /
• 1998.10a
• /
• pp.351-358
• /
• 1998

• Proceedings of the Korean Geotechical Society Conference
• /
• 2008.03a
• /
• pp.242-250
• /
• 2008

Lining systems are used for two purpose in landfills : as covers to minimize leachate generation and surface water contamination by providing a barrier from precipitation and other percolating waters, and as containment liners to contain leachate and minimize its downward migration into underlying groundwater. So identifying leaks in landfill liners is an essential part of waste management. There are many leakage detection systems to monitor and seek leakage location, such as two electrode method, electrode grid method, diffusion hoses, capacitance sensors and tracers sensing cables. However, most of them can be applied in the new landfill construction sites because sensors must be installed prior to work. This paper presents a new type of leakage detection system, so called fence type electrode arrangement system, to monitor leakage and to seek leakage location in working landfill as well as new landfill. This system is based on the measurement of an electrical current flowing through leakage point. Series of laboratory tests are performed to investigate an availability of this system and this paper present some of these results.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2002.03a
• /
• pp.321-328
• /
• 2002

Various geosynthetics used as liners or the Protection layers are installed in the solid waste landfill. The interface shear strength between geosynthetics installed at the slope of the landfill is a very important variable for the safe design of bottom and cover systems in the solid waste landfill. The interface shear strengths between (1) Geomembrane(GM)/Geotexile(GT) and (2) Geomembrane(GM)/Geosynthetic Clay Liner(GCL) were estimated by a large direct shear test in this study and were evaluated by the Mohr-Coulomb failure criterion. Especially, this research is focused on the effect of water which exists between geosynthetics because interfaces become easily wet or hydrated by rain, leachate and groundwater beneath liners. The strength reduction at large displacement and the effects of the magnitude of normal stresses and GCL hydration methods also investigated. The test results showed that the interface shear strength and shear behavior varied depending upon the magnitude of normal stresses, water at the interface, and hydration methods. Summary of secant friction angles, which could be used as reference values at a site where similar geosynthetics are installed, together with normal stress and hydration condition are presented.