• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.477-477
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• 2018

하천의 제방은 하천수의 범람을 방지하기 위하여 인공적으로 만든 구조물로서, 유수의 흐름을 일정하게 하고 자연재해에 대하여 제내지를 보고하기 위한 목적도 있다. 제방은 제내지와 제외지의 수위차로 인해 발생하는 파이핑, 제방의 월류, 사면의 탈락 등으로 파괴가 발생되고, 제방의 파괴는 제내지의 인명, 토지, 건물 등에 많은 피해가 발생한다. 이러한 제방의 파괴를 방지하기 위하여 제방 사면의 호안, 차수벽, 수제 등을 설치하고 있으며, 구조물 외에도 제방 응급복구를 위한 모래주머니, 비탈면 보호 시설 등을 이용한 피해방지에 대한 대책을 세우고 있다. 제방 구조물의 대부분은 콘크리트를 이용한 고강도 재료를 사용하여 설치되고 있으며, 재료의 환경성에 대한 문제점이 대두되어 왔다. 이에 따라 코코넛껍질을 이용한 사면 보호공, 고강도 식생매트를 이용한 사면 보호 등 친환경 재료를 이용한 사면보호 공법에 대한 연구들이 다양하게 진행되어 왔다. 본 연구에서는 미생물을 이용하여 사면을 보호하기 위한 블록 및 피복기법에 대한 연구를 진행하고 있으며, 다양한 환경성 및 무독성 검증도 병행중에 있다. 그 중 본 연구에서는 신소재와 황토, 모래, 석고를 다양한 비율로 조합하여 블록으로 활용하기 위한 일축압축 강도 실험을 수행하였으며, 신소재의 소류력 저항능력을 실험하기 위하여 안동 하천실증연구센터의 급경사 수로에 신소재를 피복한 시험구를 조성하고 5m/s 이상의 유속에서 저항능력 실험을 수행하였다. 본 연구에서는 본 실험 결과를 기반으로 하여 추후 다양한 친환경 재료를 이용한 조합을 통해 기존 콘크리트 블록에 준하는 강도를 발현할 수 있는 신소재 블록의 개발을 목표로 하고 있다.

• Journal of the Society of Disaster Information
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• v.15 no.1
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• pp.121-132
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• 2019

Purpose: This study aims to analyze the meaning of architectural space of Alvar Aalto, which is based on architectural theories of periodic flows and the form of the space with the various elements applied to the works. Method: It analyzes the interrelationships of light, form and material in triangular composition by synthesizing the architectural vocabulary of Alvar Aalto from the viewpoint of modernism. Results: The architectural works of Alvar Aalto are centered on the combination of light, form, material, and space diversity, emphasizing social awareness and linking the human scale with the building environment. Conclusion: The structure of the Alvar Aalto is a synonym of nature and culture, society and individuals, standardization and diversity, universality and locality, intellectual and emotional, scientific and human psychological. It is possible to apply reciprocity elements to architectural spaces in a comprehensive manner while being different from each other in terms of rationality and immediacy.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.5
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• pp.429-436
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• 2014

This paper presents the seismic performance of a geometrically unsymmetrical reinforced concrete building considering torsional effect and material nonlinearity of concrete and steel. The reinforced concrete building is a structure for seismic performance evaluation in the SMART-2013 international benchmark program. Nonlinear constitutive models for concrete and steel were constructed, and their numerical performance was demonstrated by various local tests. Modal analysis showed that the first three natural frequencies and mode shapes were close to the experimental results from the SMART-2013 program. In the time history analysis for low-intensity seismic loadings, displacement and acceleration responses at sampling points were similar to the experimental results. In the end, nonlinear time history analysis was conducted for Northridge earthquake to predict the behavior of the reinforced concrete structure under high-intensity seismic loadings.

• Journal of the Korea Institute of Building Construction
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• v.16 no.1
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• pp.9-15
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• 2016

The part of a building with the biggest energy loss is the exterior and many studies are actively conducted to reduce the energy loss on that part. However, most studies consider the window frames and insulation materials, but many studies do not discuss the concrete that takes more than 70% of the exterior. In order to minimize the energy loss of buildings, it is necessary to enhance the concrete's insulation performance and studies need to be conducted on this. Therefore, this study used a micro foam cell admixture, calcined diatomite powder, and lightweight aggregates as a part of a study to develop a type of concrete with improved insulation performance that has twice higher thermal conductivity compared to concrete. It particularly secured the porosity inside concrete to lower thermal conductivity. As a result of the experiment, the slump and air capacity showed fair results, but all mixtures containing micro foaming agent showed 14.3~35.1% lower mass per unit of volume compared to regular concrete. Compressive strength decreased slightly due to the materials used to improve the insulating performance, but it all satisfied this study's target strength(24MPa). Thermal conductivity was up to twice higher than that of regular concrete.

• Journal of the Korea Institute of Building Construction
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• v.10 no.1
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• pp.193-198
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• 2010

This study aimed at presenting the improvement plan for estimation of the repair and replacement cycle to analyze these current problems by considering the repair and replacement cycle theoretically and examining estimation status of home and abroad, and then drawing implication and problem based on brainstorming and expert opinion. The findings of a study is as follows. First, the problem is, for the domestic, that there is no clear standard of division to the cycle of repair and replacement and the repair and replacement cycle considering capability to deal with the change by construction method, development of the function of material and the number of years of progress is not being applied. That is, an estimation of economical repair and replacement cycle which considers the case that a large scale repair with the level of remodeling is done between 25 years and 35 years is necessary. For estimating the repair and replacement cycle, foreign country is providing this according to the use or the level of function of a building, but it is not the case for the domestic. A characteristic of each building should be reflected and the standard of estimation of the repair and replacement cycle to new construction material or method should be prepared to improve this. In addition, the method of classification of the subject item for the repair and replacement is necessary to be reorganized to be able to apply the standard of initial construction item of a building. Also, it is considered that a service standard which can reset the repair and replacement cycle based on status of a building with escape from the existing definite setup of the repair and replacement cycle through the management of background data of the repair and replacement is going to be necessary.

• Korean Journal of Heritage: History & Science
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• v.54 no.4
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• pp.4-21
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• 2021

The purpose of this study is to examine the names and types of walls constructed in the late Joseon Dynasty in YeonggeonUigwe, a record of construction works of the Joseon Dynasty, and to examine the current status and name of walls constructed in the main hall and the Yeongnyeongjeon Hall of Jongmyo Shrine. The results of the study are as follows. First, the name of the wall can be divided into four types depending on the characteristics, including direction, location, shape, function, material, and complexity, and was used as a compound word in front of the wall. Second, some of the wall types related to the material were found to have differences in the timing of theypes of walls. Since the 18th century, the use of earthen walls has been reduced, and the use of wooden walls and paper walls are often used. Third, the walls of the Jongmyo Shrine were composed of a mud wall and a fireproof wall. A fireproof wall was installed in the main hall, including a pillar, while the Yeongnyeongjeon Hall was installed only between the pillar and the pillar. Fourth, the Gap Wall can be defined as the "wall constructed at the upper part of the chamber used in the construction of the building in Jongmyo." This study is meaningful in that it attempted to clarify the definition of a wall in the late Joseon Dynasty by examining the names and examples of walls used in the late Joseon Dynasty, focusing on walls that lacked research in familiarity.

• Tunnel and Underground Space
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• v.19 no.6
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• pp.534-544
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• 2009

The collapse of the underground cavity can cause the abrupt local subsidence of the ground surface. It can be hazardous to the stability of road and building for human activity. Therefore it is necessary to develop reinforcement methods for the filling of the underground cavity. This study was executed to improve the material quality and systems to fill the calcium-aluminate mineral $(C_{12}A_7)$ environmentally, and minimize the loss of filling materials for the steep underground cavity. Filling material which was developed in this study is composed of rapid hardening material and additives. The developed material had rapid hardening and non-separation ability in the water cavity condition, so it made the effective underground dam in the cavity with prevention of material loss when it was poured in the water cavity. Results of heavy metal leaching test for environmental assessment showed that it was environmentally suiTable material for the filling in the mine cavity.

• Journal of the Korean Geosynthetics Society
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• v.7 no.2
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• pp.1-5
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• 2008

The differential settlement on ordinary concrete buildings and paved roads are often occurred and which caused the failure of structure. The grouting method can be used for correcting the settlement of the structure. However, the grouting method has a disadvantage like that it takes a long time period to get a desired strength, and it is not a continuous in the phase of reinforced effect. In this paper, as an injecting material called GPCON to complement disadvantage, it is estimated about the characteristic that has a high-density expansion. With the changing of ground conditions and amount of injection, the change of physical strength on compression, the stability against chemical material are studied through the filming of SEM. The physical strength with compression is developed to high strength due to mixing with other material. It is not react with most of the material on chemical conditions except the component of alcohol. Through the SEM test. it is confirmed that the strength of material was increased as formation is being densified.

• Korean Journal of Construction Engineering and Management
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• v.1 no.2 s.2
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• pp.53-62
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• 2000

A concrete element is obtained through multi-steps, and its quality is affected by site conditions and control constituents of procedures. In these regards, in order to assure designed qualities of concrete and associated materials of the element good quality control method is necessary in various procedures. The existing quality control measures do not satisfy the requirements for the quality control activities at each production step. This study provides a more effective checklist for each phase of concrete work, which improves existing quality control checklist through extensive research on current practices and surveys from expertises. This paper also proposes the application of multi-facet codes to develop a customized checklist to improve the efficiency in field practices and the effectiveness in assuring the designed performance of concrete. This study finally provides a more effective checklist for each phase of concrete work by improving usability of the developed project sensitive matric quality control checklist through application experiments on construction project sites.

• Journal of the Korea Concrete Institute
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• v.26 no.3
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• pp.343-350
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• 2014

A probabilistic construction stage analysis using the Monte Carlo Simulation was performed to address the effects of uncertainty regarding the material properties, environmental factors, and applied forces. In the previous research, creep and shrinkage were assumed to be completely independent random variables. However, because of the common influencing factors in the material models for the creep and shrinkage estimation, strong correlation between creep and shrinkage can be presumed. In this paper, an Monte Carlo Simulation using CEB-FIB creep and shrinkage equations were performed to actually evaluate the correlation coefficient between two phenomena, and then another Monte Carlo Simulation to evaluate the statistical properties of axial strain affected by partially correlated random variables including the material properties, environmental factors, and applied forces. The results of Monte Carlo Simulation were compared with measured strains of a column on a first story in a 58-story building. Comparison indicated that the variation due to the uncertainty related with the material properties were most severe. And measured strains was within the range of mean+standard deviation.