• Journal of the Korean Society of Safety
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• v.27 no.5
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• pp.126-134
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• 2012

The purpose of this study is to investigate waterproofing performance of self adhesive sheet combined polymer resin and poly-iso butylene. For the performance estimation of external waterproofing of concrete underground structures, there can be required various properties such as adhesion strength, hair crack resistance, repeat low and high temperature test, and so on. In this study, there engineering properties of composite system using polymer resin and poly-iso butylene were examined and could be confirmed to satisfy the guidelines of KS. Especially, it was turn out that the adhesion properties was excellent and high crack-resistance up to 1.49mm will be perform.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.761-764
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• 2005

Epoxy resin, as no-hardening, applied for repair and finish materials is used to mix together with hardener. It is advantages that epoxy resin has reaction shrinkage less than other materials and has excellent in water proofing, thermal resistance. The other hands, because ratio of combination of epoxy resin and hardener is fixed, it is not possible to change according to field condition. This investigated suspended time by temperature and hardener ratio. As a results of study, it can select economical ratio of the epoxy resin and hardener according to site situation.

• The Korean Journal of Food And Nutrition
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• v.23 no.1
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• pp.8-14
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• 2010

This study was carried out to develop an optimum baking formula and baking process for a new bread raw material with added Cordyceps militaris powder, which has been known to prevent various adult diseases and cancers. The rheological properities of dough made from Cordyceps militaris powder-wheat flour with 0, 1, 2, and 3% Cordyceps militaris powder added-were investigated. A farinogram showed that the water absorption and weakness value of dough increased with added Cordyceps militaris powder, but development time and dough stability were decreased. An extensogram showed that resistance to extension was increased in bread with 1% Cordyceps militaris powder, but decreased in bread with 2% and, 3% powder. Extensibility decreased fermentation progressed. An amylogram showed that gelatinization point was increased but maximum viscosity was decreased with added Cordyceps militaris powder. With increased amounts of powder dough volume during fermentation was reduced. The change in pH values of dough after mixing, fermentation, and proofing decreased with increased amounts of added powder.

• Journal of the Korean Society of Safety
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• v.10 no.1
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• pp.28-34
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• 1995

To improve fire proofing characteristics of protective coating using ternary soluble silicate from two component mixture, the method of reducing solubility, increasing intumescence and protection time have been studied. Intumescence and solubility of ternary silicate mixtures were dependent on many kinds of water release and the strength of cation cross-links between polysilicate particles. Especially the effect of additive, for example, corn starch was investigated. However the solubility of ternary mixture is decrease in order of Na$^{+}$ >K$^{+}$ >Li$^{+}$, and the magnitute of intumescence is increased $K^{+}$ >Na$^{+}$ >Li$^{+}$.}$ +/.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.05a
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• pp.49-52
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• 2006

Epoxy resin has less reaction shrinkage, has better water proofing and thermal resistance than other repairing materials, to it has been applied broadly to repair and finish buildings and infrastructures. Although the ambient temperature constructed is varied with the seasons and epoxy resin has to mix with appropriate hardener due to the non self-hardening, as the real construction of it, the ambient temperature is ignored and the blending ration of epoxy resin and hardener is fixed. Also, because of the hardening time is aimed to temperature condition and the tolerance of blending ratio, we investigated the variation of viscosity according to ambient temperatures and hardener ratios. As a results of study, we can select the economical blending ratio of the epoxy resin and hardener according to site situation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.6-7
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• 2019

In order to solve problems such as scattered dust, dust and chemicals harmful to the human body, workability in a confined space, quality performance, and the like generated during the field construction of the conventional waterproof sheet construction method, a waterproof sheet is used as a PC formwork, Which is produced by pouring concrete after PC installation, and evaluating the applicability of the development method in comparison with the construction method of polypropylene waterproof sheet construction method and the construction period, safety, quality, construction cost.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.23-24
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• 2015

As this study is an experiment for solving problem on the carbonation acceleration of high volume admixture concrete, the capillary pore getting filled up by saponification as cooking oil gets absorbed to the concrete surface in case of applying a cooking oil based coating agent to the concrete has been verified in the previous studies. Accordingly, this study has performed a comparative experiment on the cooking oil and the anticorrosive coating agent sold on the market while the result followed by this experiment has shown the fact of indicating similar carbonation penetration depth and porosity.

• Proceedings of the Korea Concrete Institute Conference
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• 1991.10a
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• pp.93-98
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• 1991

Polymer-Impregnated Concrete(PIC) can be considered composite material of concrete and polymer and has superior properties compared to conventional cement concrete, such as strength, stiffness, toughness, durability, water-proofing, chemical resistance. However, so far, the usage of PIC has been limited to repairing materials and non-structural applications, due to the lack of the design criteria and the analytical model to determine structural behavior. The objective of this study is to define the stress-strain response and strength characteristics of PIC in uniaxial and various biaxial compressive loading. On the bases of experimental results, general stress-strain relation, biaxial failure envelope and strength evaluation formular of PIC made with normal aggregate and methylmethacrylate(MMA) are proposed.

• Journal of the Korean Society of Safety
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• v.8 no.2
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• pp.30-38
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• 1993

To increase fire proofing characteristics of protective coating based on soluble alkali silicate, silicate coatings were studied on thermal properties, IR spectroscopy, solubility and intumescence. Intumescence and solubility of the samples were dependent on the strength of cationic cross-links between polysilicate particles. The degree of intumescence and solubility decrease K-silicate > Na-silicate > Li-silicate in the order. Especially Si$_2$O$_{5}$ $^{-2}$ crystalline regions were found to exist in Potassium silicate sample. Mixture of two kinds of silicate, for example, Lithium silicate when added to sodium silicate or potassium silicate was find to significantly reduce efflorescence and increase water resistance. This appears to be a result of stronger crosslinking between polysilicate particles by the small lithium cation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.85-86
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• 2020

In securing durability of underground structure non-exposed waterproof materials, the company aims to improve durability of waterproof materials by studying more realistic weather conditions than KS standards and developers' durability standards. Analyzing the actual climate data in Korea and the temperature of the basement layer, it is a waterproofing sheet method, a self-adhesive sheet method in which a film and a compound, which are currently widely used as underground water-proofing, and a self-adhesive waterproofing sheet method, etc. We would like to present the guidelines necessary to prevent the temperature situation and waterproof defects that are ideal for setting the endurance conditions later.