• Journal of the Korean GEO-environmental Society
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• v.6 no.4
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• pp.13-26
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• 2005

In this study, research results on organic and inorganic pollutant migration through single and composite liner were summarized. On the basis of these summarized research results, a design program for landfill liner, which can be used to optimize the liner thickness based on the allowable ground water criteria around the landfill subsurface, was developed. A reasonable liner thickness was obtained from the program output results, in the case of the migration of $Cl^-$ ion through a single clay liner. Therefore, the developed program could be used to carry out a preliminary design for landfill liners with respect to organic and inorganic pollutants.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.6
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• pp.541-554
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• 2023

The utilization of underground spaces in relation to tunnels and energy/waste storage is on the rise. To ensure the stability of underground spaces, it is crucial to reinforce rock fractures and discontinuities. Discontinuities, such as joints, can weaken the strength of the rock and lead to groundwater inflow into underground spaces. In order to enhance the strength and stability of the area around these discontinuities, rock grouting techniques are employed. However, during rock grouting, it is impossible to visually confirm whether the grouting material is being smoothly injected as intended. Without proper injection, the expected increases in strength, durability, and degree of consolidation may not be achieved. Therefore, it is necessary to predict in advance whether the grouting material is being injected as designed. In this study, we aimed to assess the injection performance based on injection variables such as the water/cement mixture ratio, injection pressure, and injection flow using UDEC (Universal Distinct Element Code) numerical program. Additionally, numerical results were validated by the lab experiment. The results of this study are expected to help optimize variables such as injection material properties, injection time, and pump pressure in the grouting design in the field.