• Journal of the Korean Institute of Rural Architecture
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• v.21 no.4
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• pp.45-52
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• 2019

Chemical grouting method is mainly used for construction of dams and reservoirs, stabilization and reinforcement of slopes, reinforcement of soft grounds such as embankments, dredging and landfills, the order of earthquake response method, and the reinforcement of structures. Recently, it is widely applied in construction sites such as highways, airfields, high-speed railways, subsea facilities, port construction works, tunnels, and subway works. As such, the demand for grouting continues to increase. The development of the grouting method was focused on increasing the strength of the ground, and the development of the chemical additives, the injection device, and the stirring device were mainly performed. But ordinary portland cement used for grouting is a product that consumes natural resources such as limestone, generates a large amount of greenhouse gases, consumes a large amount of energy sources, and it is time to develop products and new methods to replace them. In this study, Ordinary Portland Cement and New Grouting Binder (circulating fluidized bed boiler fly and blast furnace slag) were compared and analyzed by the following test. Homo-gel strength and homo-gel time, water quality analysis of the water used and soil contamination process tests of homo-gel samples were performed. In the case of NGB, when Using water is used as the reservoir water, the strength measured smaller than that of the other water. However, it shows about 2.5 times greater than the homo-gel compressive strength applied to OPC (7-day, reservoir water), so there is no problem with water quality when applied.

• Journal of the Korean Geotechnical Society
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• v.26 no.9
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• pp.47-58
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• 2010

This paper presents the injection efficiency of 2.0 shot system which was verified by strength and injection time. In order to perform this study, laboratory model tests and field tests are carried out. The laboratory model tests consist of the test of injection time for verifying the injection ratio, and the tests of homo-gel and sand-gel strengths for estimating the characteristic of strength. It is found that the injection ratio of 1:2 shows the best seepage into the ground. The results of the strengths are also larger than other injection ratio. The large strength will also be expressed by field tests at construction site.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.689-696
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• 2003

In this study, ordinary portland cement, slag cement and micro cement which have been used in the construction fields were evaluated for the environmental effects and compression strength characteristics for curing solution. To find the leaching of C $r^{6+}$ characteristics in cement grouts, C $r^{6+}$ content tests were performed for the raw materials(cement powder). In addition, C $r^{6+}$ leaching tests were peformed for the homo-gel samples according to change of pH and each curing solution with the deionized water and leachate. Then, the unconfined compression strength tests were peformed with the homo-gel samples and the amount of changed C $r^{6+}$ was measured by curing solution.

• Journal of the Korean GEO-environmental Society
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• v.11 no.9
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• pp.47-53
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• 2010

This study was made on the fact that the compressive strength characteristic of the recently developed alkali silica-sol chemical grout material was examined, whose grout material used for this study was designed to understand its strength property through the uniaxial compressive strength test(homo-gel, sand-gel), permeability test, deflection strength test, etc. In order to compare with the engineering characteristics regarding alkali silica-sol grout material and sodium silicate grout material. The uniaxial compressive strength of silica-sol grout material was identified to be increased more than 3~5 times than sodium silicate grout material at the early stage(within 72 hours). When comparing with the uniaxial compressive strengths of Sand-gel and Homo-gel at the material age of 28 days in case of silica-sol grouting material the strength of Sand-gel was measured to be about 1.3 times higher than Homo-gel. In case of silica-sol, it is assumed to have the property to exert high strength when it is actually grouted into the ground. As a result of permeability test it is judged that it is possible to apply the silica-sol to the site in the place requiring the water cut-off as the silica-sol. As a result of testing the strength at the material age of 28 days of grouting-use silica-sol showed more than 3 times' difference than the sodium silicate grouting material.

• Geomechanics and Engineering
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• v.19 no.4
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• pp.361-368
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• 2019

This study aims to evaluate the applicability of a grout material that is mixed with carbon fiber, biogrout, ground granulated blast furnace slag (GGBS) powder and cement. Uniaxial compressive strength tests were performed on homo-gel samples at days of 1, 3, 7, 14 and 28. In addition, the variation of permeability with the mixing ratios was measured. Based on the uniaxial compressive strength test, it was confirmed that the uniaxial compressive strength increased by 1.2times when carbon fiber increased by 1%. In addition, as a result of the permeability test, it was found that when the GGBS increased by 20%, the permeability coefficient decreased by about 1.5times. Therefore, the developed grout material can be used as a cutoff grouting material in the field due to its strength and cut-off effect.

• Journal of the Korea Institute of Building Construction
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• v.16 no.1
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• pp.45-52
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• 2016

In this research, characteristic properties of gel time and homo gel strength of liquid chemical grouting material for soil grouting using non-cement binder(NCB) were measured according to kinds of liquid B's Binders, W/B of liquid B's Binders and the volume ratio between liquid A and liquid B in order to examine on the applicability of soil grouting material using non-cement binder. The test was performed using NCB-1, NCB-2, NCB-3 which are environment-friendly inorganic binders developed by means of collaboration by our research team and which are different from chemical composition ratio each other. In conclusion, it was found that NCB could be applied to liquid soil grouting material using non-cement binder and replace ordinary portland cement, because NCB had the most excellent performance in certain section of gel time and homo gel strength in condition of this experiment.

• Journal of the Korean Institute of Rural Architecture
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• v.21 no.2
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• pp.35-42
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• 2019

There are 17,427 reservoirs in Korea, of which about 96% were built before the mid 1980s. Therefore, aging is severe and reinforcement are necessary. In addition, aged reservoirs, which are more than 50 years old, account for 70% of the total. Therefore, there is a problem such as the collapse of the reservoir and the decrease of the storage capacity due to progress of aging with time. The grouting method using cement is mainly used as maintenance and reinforcement method of old reservoir. However, the grouting method using cement has engineering and environmental problems. In order to solve the engineering and environmental problems of cement grouting method, an eco-friendly grouting material was developed that mixes circular resource grouting binder, high molar ratio sodium silicate and colloidal silica. The engineering and environmental properties of the developed injection materials were evaluated by conducting gel time, homo-gel strength, sea water resistance test and environmental stability evaluation. Also, examined the possibility of replacing OPC existing aged reservoir reinforcement methods. As a result, it was found out that it was better than the conventional cement method in terms of engineering and environment. However, since this study is the result of laboratory test, it is necessary of verify the application at field of aged reservoir.

• Journal of the Korean Geotechnical Society
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• v.19 no.2
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• pp.159-170
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• 2003

In this study, the mixed design of grout with hish strength.high permeation.high durability and environmental stability as the state of the art in material field was performed. Also, the subjects of grouting, grouting effects for ground conditions, and environmental effects were analyzed. According to these results, the fundamental data will be suggested as a design of grouting in the field application. The physical, mechanical and chemical characteristics with particle shape of the grouts were analyzed. Then, the gel-time of grouts, which is essential for workability and permeation range, were controlled. Also, the laboratory model grouting tests were performed to find the characteristics of solidification, permeation and durability with grouts. The ordinary portland, slag and microcement which have been used in the construction field were evaluated fur the environmental effects. To find the leaching of $Cr^{6+}$characteristics in cement grouts, $Cr^{6+}$ leaching tests were performed for the raw materials. Also, the results of leaching test were shorn by surrounding environment. Then, the unconfined compression strength tests were performed with the homo-gel samples, and the amount of changed $Cr^{6+}$ was measured by curing solution.

• Journal of the Korean Geosynthetics Society
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• v.20 no.2
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• pp.1-11
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• 2021

In this study, a study related to laboratory and pilot test were performed to use an environmental soil stabilizer developed to induce a hardening reaction similar to that of Ordinary Portland Cement (OPC) by using industrial by-products of blast furnace slag and the combustion ash of a circulating fluidized bed boiler as the main material. For this, specimens were prepared using liquid A of sodium silicate and silica sol, and liquid B of an environmental soil stabilizer (or OPC), and laboratory tests were performed to analyze the strength and environmental characteristics. And pilot test was performed on the aging reservoir, field permeability test and electrical resistivity survey were performed in the field to analyze the applicability. As a result of the laboratory test, the homo-gel compressive strength of the chemical injection material using the environmental soil stabilizer as liquid B was about 2.88 to 3.23 times greater than that of OPC. In addition, the elution amount of most heavy metals was lower than that of OPC, and the survival rate in the fish, acute toxicity test was 100%. Therefore, when judged based on the results of the laboratory test, it was analyzed to be superior to OPC in terms of strength and environment. In the results of the pilot test in the aging reservoir, when the environmental soil stabilizer was reinforced with liquid B of the chemical injection material, the coefficient of permeability in the aging reservoir decreased to 1/50 level. In addition, as a result of the electrical resistivity survey, it was analyzed that the electrical resistivity inside the aging reservoir increased as time passed, the saturation zone disappeared, and the overall reinforcement.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.62-69
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• 2003

The aim of research is the evaluation of the $Cr^{6+}$ emission features of the liquid injection through emission experiments in varying conditions, based on a field-mixing ratio. The results showed that the content of $Cr^{6+}$ content in cement measured had an Ordinary Potland Cement (OPC) of 25.3 mg/kg, which constitute the largest portion among the other materials. Likewise, the emission experiment of homo-gel and sand-gel generally satisfied the standard of KSLT (Korea Standard Leaching Test) in waste of 1.5 mg/L, but in case of the standard of KSLT in soil the emission of OPC $Cr^{6+}$ of 4.85 mg/kg. These conditions is a little exceeded the criteria in the ‘Ga’ area in terms of Korea Soil Environmental Preservation Law. In addition, results generated by the mock-up injection facilities revealed that $Cr^{6+}$ emission increased as Water/Cement and injection pressure increased. At injection pressure higher than 4 kg/㎤, $Cr^{6+}$ emission exceeded the water preservation standard of 0.5 mg/L. Similarly, a pattern experiment of C $r^{6+}$ emission according to pH was conducted, in order to evaluate the $Cr^{6+}$ emission features of grout materials in leachate below pH 5 such as pH 4 acid rain or landfill. Results show that $Cr^{6+}$ emission dramatically increased in high acidic or basic state. It indicates that $Cr^{6+}$ emission will probably increase in an environment where grout materials are injected. On the other hand, concentration of leachate was determined in areas where grout materials are used. The results show that the concentration of emission in an ultra purity condition does not manifest intensity, and is affected in the OPC>MC>SC order. It means that the pollutants or $Cr^{6+}$ emission increases with decreasing concentration. As such, $Cr^{6+}$ emission will probably exceed the countermeasure criteria according to the types of gout materials. Similarly, high pressure or injection will cause increased $Cr^{6+}$ emission. Therefore, the selection of materials or mixing ratio should be considered in general as well as according to specific industries, based on the strength and pH of $Cr^{6+}$ emission.