• Proceedings of the Korean Geotechical Society Conference
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• 2005.10a
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• pp.581-590
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• 2005

The grouting method is widely used as the impermeable effect and ground reinforcement in construction. But, it has a problem that cement and grout material are not mixed well in the injection tip equipment and an opposite flow and interception state of the chemical grouting is happened. so, continuous work is difficult. McG method installed a special grouting and device, made possible go well mixing of grouting material and prevent flowing backward and block of nozzle also diversify powder rate of cement that is grouting material to select sutible material in layer conditions. YSS that lowered $Na_2O$ influencing durability and circumstance is developed by gel-forming reaction material. so eco-circumstance and durability is increased by minimizing dissolution of underground water. In this study, it is assumed that seepage state of the injection material using a special injection tip equipment and a unconfined compressive strenth by mixing a various injection material of various. And it is confirmed that strenth increase effect and permeable decrease of the improved body through the test execution and field execution.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.57-58
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• 2011

In the experiment, we add to NaOH, Ca(OH)₂ and Calcium Hydroxide as the Slag stimulus also mixed the cement stimulus such as NaSCN, TEA and CaCl₂ for improving compressive strenth of concrete which added the Blast Furnace Slag Powder at 1 and 3 days. In the result of strength test, It showed that 2percentage of activator 1 and 5percentage Ca(OH)₂, 1percentage of activator 3 and 5percentage of Ca(OH)₂ are higher than 100 percentage OPC.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.592-600
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• 2005

Ship have cutout inner bottom and girder and floor etc. Ship's structure is used much, and structure strength must be situated, but establish new concept when high stress interacts sometimes fatally the area. There is no big problem usually by aim of weight reduction, a person and change of freight, piping etc.. Because cutout's existence grow up in this place, and elastic buckling strength by load causes large effect in ultimate strength. Therefore, stiffened perforated plate considering buckling strength and ultimate strength is one of important design criteria which must examine when decide structural concept at initial design. Therefore, md, reasonable buckling strength about stiffened perforated plate need to ultimate strength limited design . Calculated ultimate strength varied several web height and cutout's dimension, and thickness in this investigated data. Used program(ANSYS) applied F.E.A code based on finite element method

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.29-32
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• 2005

In this study, the experiment was carried out to investigate and analyze the strenth properties and flowability of ultra-high strength concrete accroding to types of mineral admixtures. The main experimental variables were water/binder ratio 25.0, 27.5 and 30.0$\%$, water content 155, 160, 165, and 170kg/$m^{3}$ and mineral admixtures such as fly ash, silica fume and meta kaolin. According to the test results, the principle conclusions are summarized as follows. 1) In case of using admixtures, superplasticizer amount need more than plain concrete. 2) According to kinds of admixtures, the viscosity of concrete show much difference. 3) The compressive strength of concrete that use admixtures becomes low in early-age strength, but appeared by higher than plain concrete in long-term strength. 4) Meta kaolin is excellent in side but has viscosity enlargement efficiency a little. But, problem estimates that is not to make design strength 600 and 700kgf/$cm^{2}$ if use mixing condition with water-binder ratio properly.

• Journal of the Korean GEO-environmental Society
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• v.7 no.6
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• pp.113-119
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• 2006

Recently, the ground injection method using water glasses as one of the main resources and the products of these constructions have basic problems in terms of the method of constructions for the permanent foundation reinforcement and stopping leakage of water because they have some serious problems such as durability, compressive strength, injectant eluviation and so forth even though they are still used to stop leakage of water in the temporary structures. The purpose of this study is to demonstrate the strength characteristic and environment friendliness of NDS method by unconfined compressive strenth test, permeability test, length change test, leaching test, and assessment of environmental impact in comparison water glass type material. The test results show that NDS method has significant improvement of strength, permeability, volume change, and leaching. An assessment of environmental impact also demonstrates that the NDS material is environmentally friendly.

• Geotechnical Engineering
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• v.7 no.4
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• pp.49-64
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• 1991

Abstract The stabilization by lime or Portland cement has long been the most commonly used methods for clay soil. But it wart the purpose of this reserch to define the effectiveness malt content on unconfined compressive strength of limeflay mixture and cementrlay mixture. From result of a laboratary investigation, saInt content in sample soil was not concernd with variation of PH value. PH value of lime 10% mixture and of cement 10% mixture were near 12.4, 11.6 respectively. In case of more than 7 curing days, PH value and Ca++ion concentration were decreased with increasing curing time. Also the result of X-ray difflection analysib for stabilized soil by admixture 10% in 90 curing days showed that the diffrection intensity of Tobermorite and Ettringite and other reaction products was smaller in the case of addition of salt 8% than malt 0% in stabilized soil. When lime-soil mixture and cement-boil mixture were cured in 2$0^{\circ}C$ and 5$^{\circ}C$, 2$0^{\circ}C$ cured mizture produced significantly higher compressive strength than 5t cured mixture and air dry curing sample produced higher than cured sample in water. The addition of salt 2~4% in conjuntion with lime or cement may accelerate strenth gain or not prevent front However, the addition of salt 8% prevent from strength gams.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.2
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• pp.99-105
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• 2010

This paper investigated the characteristics of wasteform containing a spent zeolite used as a separating agent of FPs for recycling LiCl waste which would be generated from pyrochemical process of spent PWR fuel. In this study, a conventional borosilicate and Ca-rich glass were used as a consolidating agent for spent zeolite and it's mixing ratio was changed in the range, $25{\sim}35wt%$. The leach rates of Cs and Sr had about $0.1{\sim}0.01g/m^2day$ and $0.001{\sim}0.0001g/m^2day$, respectively. The leach resistance of Cs increased with amount of SAP and it showed about 10 times higher in the Ca-rich glass wasteform than in the conventional borosilciate glass wasteform. The compressive strength of wasteform was affected with the amount of glass. Thermal expansion rate of containing 30wt% glass has relatively lower than others. Also, the melting temperature was little changed in given mixing ratio of glass.

• Magazine of the Korean Society of Agricultural Engineers
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• v.14 no.2
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• pp.2622-2633
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• 1972

This study was attempted in order to search for phyosical properties on various mix designs of concrete as ne of studies relating top revention against corrosion by action of sea water in the West Sea. In this study, as concerete mix design, fly ash, pozzolith and vinsolresin were used as admixtures for normal portland cement respectively, and pozzolan cement and normal cement were also used for each plain concrete. Concrete specimens were made and cured in accordance with the Korean Standard Specifications for concrete. In thetest, compressive strengths of the specimens were measured at the following ages; 7-day, 28-days and 3-months. Absorption test was made by immersing the specimens in water kept at boiling temperature for 5 hours. The results obtained from the tests are summarized as follows; 1. The use of fly ash as an admixture in mix design of concrete, has an effect on compressive strength at each age. But it is actually not effective on absorption by concrete, as the result of the fly ash concrete is almost the same at that of ordinary plain concrete. 2. The use of pozzolith as an admixture in mix design of concrete, has an effect on both of compressive strength at each age and absorption rate. The pozzolith is more effective than vinsol resin, relating to improvement for physical proreties of concrete. 3. The use of vinsol resin as an admixture in mix design of concrete, has also an effect on both of compressive strength at each age and absorption rate. As the above fact, effectiveness of the vinsol resin is some what lower than pozzolith, as far as physical properties of the concrete are concerned. 4. Plain concrete used pozzolan cement only is the most effective on both of strength at each age and absorption rate in this study. The pozzolan cement is characteristic of higher strenth as the age is later. 5. Relationship between compreessive strengths and absorption rates of the concrete is shown by a different regression line dependingon ages. The gradient of the regression line is steeper as the age is later. 6. Throught physical test, it may be expected that the use of pozzolith and vinsol resinas asan admixture respectively will be better resistant than fly ash or ordinary plain concrete and that plain pozzolan concrete will also be the best resistant to action of sea water due to improvement of theirphysical properties.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.5
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• pp.82-91
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• 2011

In this study, 24 prototype specimens were tested to find out the shear behavior and strength of large anchorage system exceeding 50mm(2") in anchor bolt diameter($d_0$) and 635mm(25") in effective embedment depth($h_{ef}$) not addressed by ACI349-06 Appendix B. Test variables are anchor bolt diameter($d_0$ = 63.5, 76.2, 88.9mm), effective embedment depth($h_{ef}$=635, 762mm), and edge distance($c_1$=381, 508, 762mm). Concrete compressive strength is constant($f_{ck}$=38MPa). Test results ($V_{test}$) were overestimated by $V_{aci06}$(shear strength by ACI 349-06) and $V_{ccd}$(shear strength by CCD method). In large anchorage system exceeding 50mm(2") of anchor bolt diameter($d_0$) and 635mm(25") of anchor bolt effective embedment depth($h_{ef}$), the bolt diameter variation and effective embedment depth($h_{ef}$) has no influence on the shear strenth, But, according to the analysis results of the feature ratio on edge distance($c_1$) and anchor bolt diameter, the feature ratio become smaller, which means anchor bolt diameter is bigger, predicted ratio of test results and predicted equation is larger. It was found that anchor bolt diameter is immediate cause of deterioration in the shear capacity of large anchorage system. To improve and extend the validity of current design recommendations further theoretical and numerical work is needed.