시공성의 변화요인이 콘크리트의 특성에 미치는 영향

柳顯紀 충주대 2003 産業科學論文集 Vol.11 No.-

An experimental work is performed to analyze the properties of watertight which is generated during the course of construction of concrete structure. The result which has been analyzed on the general properties for construction condition according to the pouring time, the effect of laitance, the mechanical concrete, the properties of watertight using water proofing agent, is summarized as the following. The more increasing W/C, the more passing time the absorption content and permeability content increase with the properties of watertight. The absorption content is low in the case of mixing water proofing agent compared to the plain concrete. The absorption and permeability content is lower in the case of removing laitance.

산업부산물을 이용한 고성능 콘크리트의 특성에 관한 연구

류현기,윤승조 충주대 산업과학기술연구소 1999 産業科學論文集 Vol.7 No.2

This is study intended to develop the high performance concrete by using Fly Ash, Silica Fume and Expansive Additives in order to prevent the crack from caused by dry-shrinkage and get the economical efficiency. Form the test results, the optimum addition rate based on the fluidity, segregation resistibility, strength and length-change test can be achieved at 5% of Expansive Additives in the combination of 15:5 (Fly Ash : Silica Fume).

장기재령 경과에 따른 콘크리트의 수밀특성

柳顯紀 충주대학교 산업과학기술연구소 2002 産業科學論文集 Vol.10 No.-

The watertight of concrete can be controled by the characteristic of aggregate and how to construct. Generally, it is considered by resistance to hygroscopic property and water & vapour permeability. This study is about analyzing watertight during the process of constructing any structures and tries to analyze the watertight change according to passing time after pouring water and watertight change

鑛山廢棄物을 굵은 骨材로 이용한 콘크리트의 力學的 特性分析

柳顯紀 충주대학교 1997 한국교통대학교 논문집 Vol.32 No.2

This study analyzes and expriments the research on the actual condition, the productive amounts of mine-waste and the possibility to be applied, focused on mines in Chung-buk area as a basic research in using mine-waste for the aggregate of concrete. The results in concrete application of mine-waste by suggesting the evalution method called for the index of slump strength, and we could evaluate the possibility for coarse aggregate. But even though physical characteristics in some mines were good, it was evaluated as the faulty result by this method in some mines.

무기질 혼화재를 이용한 시멘트 모르터의 특성에 관한 연구

柳顯紀 충주대 2001 한국교통대학교 논문집 Vol.36 No.2

The objective of this study is to analyze the fundamental groperties of fresh and hardened cement mortar with various addition rations of the inorganic admixtures and expansive additives.As the results of the test, the flow and air content increase with the addition of expansive additives.And as the replacement rates of fly ash and silica fume increase, the flow shows a decline.At hardened state, the compressive strength and flexual strength decrease with the addition of inorganic admixtures, expansive additives and zinc stearates.With the increase of silica fume's replacement, they show a little decrease at early age and then increase gradually.Also, absorption and permeability show a steep decrease when zinc stearates is added, and a slack decrease with the replacement of silica fume.

충남대학교 공업기술 계열 교사 연수 프로그램에 대한 만족도 분석

류창열,최유현,김판욱,김기수,김태훈,이창훈 忠南大學校 工業敎育硏究所 2005 論文集 Vol.27 No.1

The purpose of this study was to analyze the educated teachers' satisfaction of the in-service education programs of industrial technical and technology teachers in Chungnam National University. This study was carried out through survey to accomplish the purpose. The number of questionnaires collected was 86. This study used the SPSS program to conduct a descriptive analysis of the data. The results of this study were as follows: (1) The satisfaction about 'teachers' participation', 'utilization of audiovisual materials and instruments' and 'level of professor and lecture' was relatively high. (2) The satisfaction about 'environments of in-service education programs', 'evaluation of achievement', and 'efficacy of lectures' was relatively low.

팽창재 치환율 변화에 따른 콘크리트의 팽창 특성에 관한 연구

柳顯記 충주대 산업과학기술연구소 2000 産業科學論文集 Vol.8 No.-

Recently, the expansive additives are used in construction fields in order to reduce the shrinkage cracking occured in concrete structure. Hower, the expansive additives sometimes may be over added due to insufficiency of congnition of constructor, which results the decrease of strength and over expansion. So in this study, the experments are perfomed to present the properties of concrete by varying the unit additions of expansive additives. As the results. The concrete shows a decrease of strength and a increase of cracking with the increase of unit addition of expansive additives which causes the self destrution of concrete specimens.

배합 및 시공조건의 변화에 따른 고강도 콘크리트의 특성분석

류현기 忠州大學校 2003 한국교통대학교 논문집 Vol.38 No.2

This is a paper for the experiments to analyze the properties of watertight which is generated during the course of construction of High Strength concrete structure. The result which has been analyzed on the general properties for construction condition according to the pouring time, the effect of laitance, the mechanical concrete, the properties of watertight using water proofing agent, is summarized as the following. The more increasing W/C, the more passing time the absorption content and permeability content increase with the properties of watertight. The absorption content is low in the case of mixing water proofing agent compared to the plain concrete. According to the existence and nonexistence to the removing laitance the absorption and permeability content is lower in the case of removing laitance rather than in the case of not removing laitance.

증점제를 이용한 일반강도 고유동 콘크리트의 특성에 관한 연구

류현기 忠州大學校 1999 한국교통대학교 논문집 Vol.34 No.2

Recently, great efforts and investment have been ceaselessly made in oder to accomplish economical production by applying new methods like minimanization of man-power into construction field, because there have been increasingly the avoidance of 3D works, on the decrese of skilled labors and old age of skilled labors. AS above situation, high fluidity concrete has been spotlight in construction field. Accordingly, in this study, from the standpoint of view for developing the high fluidity concrete that compacting is not reguired within the range of 210~300kg/cm2 of compressive strength, we have been focused on the development and practical of compressive strength, we have been focused on the development and practical using of high-fluidity concrete with viscosity agent, which can prevent segregation resulting from flowing highly normal concrete by applying superplasticizer. The main agent and flyash replacement is combi ned, high-fluidity concrete with high quality can be accomplished.

鑛山廢棄物을 骨材로 이용한 시멘트 모르터에 관한 實驗的 硏究

柳顯紀 忠州大學校 1996 한국교통대학교 논문집 Vol.31 No.2

To use the waste in complementing the insufficient amounts of natural aggregate resource the provides the great effect. So, this study analyzes and experiments the research on the actual condition, the productive amounts of mine--waste and the possibility to be applied, focused on mines in Chung-buk area as a basic research in using mine-waste for the aggregate of concrete. The results are as follow : In analyzing and experimenting mortar and concrete application of mine-waste, by suggesting the evaluation method called the index of flow, strength, we could evaluate the possibility for aggregate. But even though physical characteristics in some mine were good, it was evaluated as the faulty result by this method in some mines.