• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.349-354
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• 1999

Specialty cellulose fibers processed for the reinforcement of concrete offer relatively high levels of elastic modulus and bond strength. The hydrophilic surfaces of specialty cellulose fibers facilitate their dispersion and bonding in concrete. Specialty cellulose fibers have small effective diameters which are comparable to the cement particle size, and thus promote close packing and development of dense bulk and interface microstructure in the matrix. The relatively high surface area and the close spacing of specialty cellulose fibers when combined with their desirable mechanical characteristic make them quite effective in the suppression and stabilization of microcracks in the concrete matrix. The properties of fresh mixed specialty cellulose fiber reinforced concrete and the contribution of specialty cellulose fiber to the restrained shrinkage crack reduction potential of cement composites at early age and theirs evaluation are presented in this paper. Results indicated that specialty cellulose fiber reinforcement showed an ability to reduce the total area significantly (as compared to plain concrete and polypropylene fiber reinforced concrete.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.216-217
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• 2014

Optimum finishing position, thickness and phase change temperature of winter and summer season were selected and suitability of finishing materials was evaluated based on temperature measurement of specimens applying the coating material mixed phase change materials(PCM). As a result, when finishing position was interior and finishing thickness of coating material mixed n-Octadecane(28℃ PCM) was 4mm, thermal performance was effective. n-Octadecane in summer season and n-Hexadecane(18℃ PCM) in winter season are indicated effective on energy savings, respectively.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.98-99
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• 2014

The newly developed eight-directional collector was installed at five different locations in the coastal area after its functionality was verified through experiments. Based on the airborne chloride amount measured for one year, the distribution characteristics of airborne chlorides were examined by direction. In terms of direction, a large amount of airborne chlorides was collected, not only in the direction facing the coast but also in the opposite direction. The amount measured at effective three directions was 1.5 times that measured at non-effective three directions.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.581-586
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• 2003

The objective of this study is to evaluate the injection performance of crack repair method in concrete structure. To improve the quality of the concrete structure caulking material was injected into the crack of building that were planned to be demolished and injection properties of various repair method were compared and assessed according to type of crack. Results from the test showed that when cracks and injection port were integrated and the injection port wasn't blocked repair material was able to be injected even below around 40㎏/㎠ pressure. Moreover, effective pressure each type of packer showed wide range varying from 200-400㎏/㎠. As for drill method for injection port, core drill method has shown to be more effective compared to the air pump method

• 한국농촌건축학회논문집
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• 제8권1호
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• pp.9-16
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• 2006

In campus project, "Barrier Free Design" is the essential part for the handicapped. It is necessary to make a quality model that choose effective design value engineering objects. So more effective models, this study examine requests of the university students. Checked items are classified into four groups that movement, guidable, safety and territoria parts, and each groups are also divided into detailed items for basic decisional elements. When basis points sets 10, it can be divided that movement parts 2.93pts, guidable parts 2.31pts, safety parts 2.41pts and territoria parts 2.35pts. in this results, we can make additive value and quality model for barrier free design in campus design value engineering.

• Smart Structures and Systems
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• 제4권4호
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• pp.465-492
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• 2008

Proper pretest planning is a vital component of any successful vibration test on engineering structures. The most important issue in dynamic testing of many engineering structures is arriving at the number and optimal placement of sensors. The sensors must be placed on the structure in such a way that all the important dynamic behaviour of a structural system is captured during the course of the test with sufficient accuracy so that the information can be effectively utilised for structural parameter identification or health monitoring. Several optimal sensor placement (OSP) techniques are proposed in the literature and each of these methods have been evaluated with respect to a specific problem encountered in various engineering disciplines like aerospace, civil, mechanical engineering, etc. In the present work, we propose to perform a detailed characteristic evaluation of some selective popular OSP techniques with respect to their application to practical civil engineering problems. Numerical experiments carried out in the paper on various practical civil engineering structures indicate that effective independence (EFI) method is more consistent when compared to all other sensor placement techniques.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2005년도 학술발표회 논문집
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• pp.153-160
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• 2005

A new nonlinear static analysis method, Effective Modal Pushover Analysis (EMPA) which can evaluate earthquake responses such as story drift and plastic rotation of plastic hinges addressing higher mode effects was developed. Unlike existing nonlinear static procedure based on properties of fundamental vibration mode, the EMPA performs nonlinear static analysis using multiple effective modes constructed by direct combination of natural vibration modes. Therefore higher mode effects can be efficiently considered. In the present study, procedures of the EPMA evaluating inelastic earthquake responese were established and the results were verified by nonlinear time history analysis. The EMPA can be applied to seismic evaluation of high-rise buildings and irregular buildings where higher mode effects become conspicuous.

• 한국철도학회논문집
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• 제9권5호
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• pp.569-576
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• 2006

Recently, many Korean firms have been adopting $360^{\circ}$ Degree Feedback System as a way of adapting to the environmental changes in business world. The reason is that the traditional top-down way of personnel evaluation pattern can not but have many limits in this turbulent changing environment. The main purpose of this article is to depict some aspects of $360^{\circ}$ Degree Feedback System including its current status quo, its positive and negative side, and the effective ways of its improvement focusing on the railway-related "A firm".

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1789-1795
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• 2007

Railroad, the structure maintenance and restoration project was increased and widely performed in concrete pavement road and airport, building at downtown area, bridge abutment, and other concrete structures. Especially, the ground reinforcement technique by quick-reaction expansible resins is the most effective countermeasures against differential settlement and undesired deformation of structure. In this paper, the unconfined compressive strength and some environmental related tests were conducted to evaluate compressive strength and environmental effect of quick-reaction expansive resins and soil mixtures. Also, three case histories of concrete structure and railroad restoration project are presented. Based on the laboratory test, the quick-reaction expansible resins and soil mixture represent the sufficient compressive strength and the leachate material is satisfied the environmental regulation limits. As a result of this study, the structure restoration technology using quick-reaction expansible resins is very effective for restoration of differential settlement and deformation, and it is environmentally sustainable technology.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.365-370
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• 2007

Foundation settlements(settlements at the embankment surface and ground) has been evaluating to satisfy the strict allowable residual settlement level from the start of the construction of Gyungbu high speed railway. This is because both embankment and ground settlement could be important to minimize the residual settlement after the construction of concrete track. Ground settlement is caused by the increase of effective stress resulting from embankment. The causes of embankment settlement could be come from different sources, for example, the increase of effective stress, rainfall, creep behaviors. Based on the field measured data, this paper analysed the settlement of ground and embankment settlement. The biggest settlement at the embankment surface was 9.7mm during 246days at the STA 000k922.5. The calculated settlement of embankment itself was 8.6mm at the same places. These results conclude that the compressive settlement of embankment could not negligible.