• Proceedings of the Korean Geotechical Society Conference
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• 2000.02a
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• pp.1-11
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• 2000

The use of Compaction Grouting evolved in 1950's to correct structural settlement of buildings. Over the almost 50 years, the technology has been developed and is currently used in wide range of applications. Compaction Grouting, the injection of a very stiff, 'zero-slump' mortar grout under relatively high pressure, displaces and compacts soils. It can effectively repair natural or man-made soil strength deficiencies in variety of soil formations. Major applications of Compaction Grouting include densifying loose soils or fill voids caused by sinkholes, poorly compacted fills, broken utilities, improper dewatering, or soft ground tunneling excavation. Other applications include preventing liquefation, re-leveling settled structures, and using compaction grout bulbs as structural elements of minipiles or underpinning. In this paper, on the basis of the case history constructed in this year, a study has been performed to analyze the basic mechanism of the Compaction Grouting. Also, the effectiveness of the ground improvement and the bearing capacity of the Compaction Pile has been verified by the Cone Penetration Test(CPT) and Load Test. Relatively uniform Compaction grouting column could be maintained by planning the Quality Control in the course of grouting. And, the Quality Control Plan has been conceived using grout pressure, volume of grout and drilling depth.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.836-843
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• 2009

The Water Glass grouting method has been applied frequently to impermeable grouting in practice. But there is raising problems which are durability decrease by passage time and environmentally adverse effect. So, Earth Natural Grouting method which uses micro cement is developed to overcomes the problems of the Water Glass grouting method. And it is displayed ground injection extent like Water Glass grouting method. For verifying impermeability of ENG, it is carried out a triaxial permeability test about manufacturing specimen of ENG, SGR method which is a presentative Water Glass grouting method. Although Coefficient of permeability, k, of SGR is measured a little high than k of ENG whose value is $a{\times}10^{-6}cm/sec$, the value of ENG belong to impermeable rage. And, k of SGR shows relatively rapid increase according to cure time due to durability decrease of water glass. Also, in-situ test result of ENG has similar value with SGR method for similar ground.

• The Journal of Engineering Geology
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• v.31 no.3
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• pp.381-393
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• 2021

Physical, mechanical, hydraulic, and geophysical tests were applied to validate methods of inspecting the effectiveness of grouting on an agricultural reservoir dam. Data obtained from series of in situ and laboratory tests considered four stages: before grouting; during grouting; immediately after grouting; and after aging the grouting for 28 days. The results of SPT and triaxial tests, including the unit weight, compressive strength, friction angle, cohesion, and N-value, indicated the extent of ground improvement with respect to grout injection. However, they sometimes contained errors caused by ground heterogeneity. Hydraulic conductivity obtained from in situ variable head permeability testing is most suitable for identifying the effectiveness of grouting because the impermeability of the ground increased immediately after grouting. Electric resistivity surveying is useful for finding a saturated zone and a seepage pathway, and multichannel analysis of surface waves (MASW) is suitable for analyzing the effectiveness of grouting, as elastic velocity increases distinctly after grouting injection. MASW also allows calculation from the P- and S- wave velocities of dynamic properties (e.g., dynamic elastic modulus and dynamic Poisson's ratio), which can be used in the seismic design of dam structures.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.414-423
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• 2006

Many construction projects adopt grouting technology to prevent the leakage of groundwater or to improve the shear strength of the ground. Recognition as a feasible field procedure dates back to 1925, Since then, developments and field use have increased rapidly. According to improvement of grout materials, theoretical study on grout penetration characteristics is demanded. Fluid of grout always tends to flow from higher hydraulic potential to lower and the motion of grout is also a function of formation permeability. Viscosity of grout is changed by chemical action while grout moves through pores. Due to the increment of viscosity, permeability is decreased. Permeability is also reduced by grout particle deposits to the soil aggregates. In this thesis, characteristics of new cement grout material that is developed recently is studied: injectable volume of new grout material is tested in two different sizes of sands, and the method to calculate injectable volume of grout is suggested with consideration of change in viscosity and clogging phenomena. The calculated values are compared with injection test results. Viscosity of new grout material is found to be an exponential function of time. And lumped parameter $\theta$ of new grout material to be used for assessing deposition characteristics is estimated by comparing deposit theory with injection test results considering different soil types and different injection pressure.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.2
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• pp.89-99
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• 1984

Engineering properties of soils is studied by permeating injection of water-glass chemical grout by use of a large sized grouting equipment of 1.5 shot system. Furthermore, the effectiveness of chemical groutinig by taking water-glass chemical grout combined with portland-cement for the purpose of improving the soil strength is confirmed. Relationships between main factors which cause the effectiveness of chemical grouting are described, and the factors are velocity and temperature of flowing water; grain size distribution and density of soils; density, viscosity, gel time and volume of grouts; injection pressure and grouting process. Improvement of the effectiveness of chemical grouting in flowing water by preventing the dilution and flowing down of grouts is investigated. Moreover, local shear failures and upheaval phenomena of ground are also investigated by field measurement.

• Food Science of Animal Resources
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• v.38 no.3
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• pp.515-529
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• 2018

The present study was designed to investigate the effects of calpain system on the formation of volatile flavor compounds in Hanwoo beef. In the first experiment (exp.1), Longissimus lumborum (LL) muscle samples were injected with solutions containing 50 mM $CaCl_2$ or 50 mM $ZnCl_2$ and 154 mM NaCl respectively, and aged for 7 d at $4^{\circ}C$. In the second experiment (exp.2), the ground LL muscle was incubated with the aforementioned solutions containing cathepsin inhibitor. The injection with $CaCl_2$ solution greatly elevated the calpain activity and concomitantly, significantly decreased the Warner-Bratzler shear force (p<0.05). The pH, meat color and cooking loss did not differ (p>0.05) between the treatment groups. A total of 51 volatile compounds were identified using the solid phase microextraction with gas chromatography (SPME-GC). Results on volatile analyses from the both experiments showed that the injection with calcium ions led to significant increase (p<0.05) concentrations of pyrazines and sulfuric compounds. These results coincide with a higher rate of protein degradation due to the $CaCl_2$ injection as compared to the control group. Significantly (p<0.05) higher levels of lipid oxidation derived-aldehydes were found in the samples with $ZnCl_2$. The exp.1 showed that cathepsin inhibitors had no effect on the formation of volatile flavor components after 7 d of aging. These results imply that the proteolytic activity of the calpain system is associated with generation of volatile compounds of chiller-aged beef, while the role of cathepsins is likely very limited.

• Journal of the Korean Society for Railway
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• v.12 no.5
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• pp.687-693
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• 2009

An algorithm and a computer software are developed for the analysis of rail potential rise. The algorithm is intended to be integrated with the traction power system simulation program. In the algorithm, rail potentials are obtained by two step process. First the injection currents to the negative rail are obtained from load-flow study. In the next step, a network consisting of negative rail and the injection currents are constructed. Leakage resistance to ground are added to the network. And the network is analyzed for rail potentials. A software is developed to verify the validity of the algorithm. The result of the software is compared with the Simulink/SymPower circuit analysis result. The differences between the two results are with the acceptable range. The advantage of this algorithm is that it can be integrated with the existing traction power supply simulation program easily, which usually ignores negative rail's leakage resistance.

• The Journal of Engineering Geology
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• v.29 no.3
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• pp.201-209
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• 2019

Bottom-up multi-stage pressure grouting is widely applied to domestic slopes and tunnels. It involves injecting earth from the ground to the surface after drilling. Various reports of construction performance have demonstrated its wide applicability. However, little research has studied top-down multi-step pressure grouting in Korea, which involves injection from the surface. This paper compares the grouting effect of both the established bottom-up method and the top-down method in soil box and field tests. The soil box test showed that the bulb volume of the top-down method is ~24% less than that of the bottom-up method. The field test confirmed that the top-down method has a wider grouting range and a higher injection density per area than the bottom-up method.

• Journal of the Korean Geotechnical Society
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• v.31 no.5
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• pp.23-33
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• 2015

In the present study, a ground heat exchanger was installed for each heat source in the system at the site to evaluate ground heat conductivity, constructability, and economic feasibility; the factors considered in the study included ground heat, groundwater, fillers (such as bentonite and pea pebbles) and the shape of the heat exchange pipe (e.g., U and D-U). The aim was to determine the ground heat exchanger appropriate for the geothermal system in the 3rd-phase construction of Incheon International Airport. A comparative cost analysis of the initial costs based on the above information showed that although the initial costs of the regular vertical closed loop-II and modified vertical closed loop were lower than those of the regular vertical closed loop-I, they could not be expected to deliver high economic efficiency from the viewpoint of constructability (filler injection, heat exchange pipe insertion). The initial costs proved to be higher in the case of Geohil.

• Tuberculosis and Respiratory Diseases
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• v.51 no.2
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• pp.166-172
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• 2001

Silicone fluid is a biomaterial widely used in modern cosmetic procedures because there are few side effects, considerable chemical stability and predictable physical properties. However, many local and systemic adverse reactions have reported. In particular some serious pulmonary complications have been reported such as pulmonary thromboembolism, acute respiratory distress syndrome with some cases leading to mortality. Most of the serious complicated cases were induced by an illegal silicone fluid injection. We experienced two cases of acute respiratory distress syndrome with pulmonary hemorrhage induced by an illegal silicone fluid injection. The patients were 41 & 51 year old women, who complained of dyspnea. The chest X-ray and HRCT scan findings showed a bilateral ground glass attenuation on the bilateral dependent portion of the upper and middle lung zone. The patients clinical symptoms and the radiologic and other laboratory findings were compatible with acute respiratory distress syndrome induced by the silicon fluid injection. Here we report two cases of acute respiratory distress syndrome with pulmonary hemorrhage induced by an illegal silicone injection with a review of the relevant literature.