• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.61-62
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• 2017

In this study, the initiation of steel corrosion was monitored due to chloride attack using embedded sensor. In general, Steel bars embedded in concrete are protected from corrosion by being forming a passive film on the surface. However, the passive film is destroyed by chemical erosion such as concrete carbonation and chloride penetration, and the rebar is exposed to the deteriorating factor and corrosion proceeds. In order to realize the initiation of steel corrosion, OCP and change of Impedance parameter were observed by using Half-cell and EIS method depending on cover depth. As result, 10mm cover showed the impedence increased in 6weeks.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.105-106
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• 2016

The study of the sandwich wall with the increasing interest in building energy consumption have been actively conducted. This study designed exposed sandwich wall in the light of energy saving design standard and thermal bridge of share connection. The heat insulating performance was analyzed U-fator using calculation program provided in passive houses association and KS F 2277 (method of measuring thermal insulation of construction component materials).

• 한국지반신소재학회논문집
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• 제10권3호
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• pp.43-51
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• 2011

본 연구에서는 수동저항부를 형성시킨 띠형 섬유보강재의 인발저항 특성을 평가하기 위해 일련의 실내인발시험을 수행하였다. 이 띠형 섬유보강재는 중간에 길이방향으로 접힘홈이 형성되어 있어 보강재를 반폭으로 접어 콘크리트 블록에 직접 체결할 수 있고 후단부에는 보강재를 '${\cap}$' 형태로 세워서 수동저항부를 형성시킬 수 있다. 이 띠형 섬유보강재는 후단부에 수동저항부가 형성되어 있기 때문에, 흙과 보강재 사이의 표면마찰저항과 수동저항부에서의 지지저항력이 함께 발현되는 인발저항 특성을 가진다. 따라서, 인발저항 평가시 마찰저항과 지지저항을 각각 산정하여 설계에 반영해야 한다. 일련의 인발시험 결과 수동저항부를 형성시키면 인발저항강도가 10~65% 정도 증가하고 수직응력이 클수록 증가량이 점차 커지는 경향을 보이는 것으로 나타났으며, 이를 근거로 수동저항부 형성에 의해 발현되는 지지저항력 산정 방법을 제안하였다.

• Earthquakes and Structures
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• 제11권6호
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• pp.1001-1025
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• 2016

Building structures generally have inherent low damping capability and hence are vulnerable to seismic excitations. Control devices therefore play a useful role in providing safety to building structures subject to seismic events. In recent years semi-active dampers have gained considerable attention as structural control devices in the building construction industry. Magneto-rheological (MR) damper, a type of semi-active damper has proven to be effective in seismic mitigation of building structures. MR dampers contain a controllable MR fluid whose rheological properties vary rapidly with the applied magnetic field. Although some research has been carried out on the use of MR dampers in building structures, optimal design of MR damper and combined use of MR and passive dampers for real scale buildings has hardly been investigated. This paper investigates the use of MR dampers and incorporating MR-passive damper combinations in building structures in order to achieve acceptable levels of seismic performance. In order to do so, it first develops the MR damper model by integrating control algorithms commonly used in MR damper modelling. The developed MR damper is then integrated in to the seismically excited structure as a time domain function. Linear and nonlinear structure models are evaluated in real time scenarios. Analyses are conducted to investigate the influence of location and number of devices on the seismic performance of the building structure. The findings of this paper provide information towards the design and construction of earthquake safe buildings with optimally employed MR dampers and MR-passive damper combinations.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.29-32
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• 2008

리모델링은 친환경적 접근 방법으로써 현재 수요가 증가하고 있는 추세이다. 리모델링 사업시 구조 부재를 동반한다. 그러므로 리모델링시에 구조적인 안정성을 확보하기 위해서는 적절한 보강 방법이 요구된다. 이 연구의 목적은 전단벽에 개구부가 발생하였을 경우 Passive 보강 방식과 Active 보강 방식을 이용하였을 때의 거동 특성을 파악하는 것이다. Passive 보강 방식은 CFS나 강판 등을 부착하여 손상 부재를 보강하는 방식이고, Active 보강 방식은 프리스트레싱을 이용한 균열 제어를 통해 보강력을 도입하는 방식이다. 실험 결과 각 실험체들은 전단 파괴 형태를 보여주었고 두 가지의 다른 보강 방식은 강도나 연성에 있어서 다른 결과를 보여주었다.

• 한국안전학회지
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• 제36권5호
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• pp.10-17
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• 2021

The controversy over the risk of the human body being affected by electromagnetic fields emitted from 60 Hz power lines continues without end. There are currently no new studies or research progress being made in this direction that is notable, and the number of civil complaints is gradually increasing. The problem is that each study produces different results, among which the effect of exposure to magnetic fields on childhood leukemia is a major one. In Korea, an electrician who was maintaining a 22.9 kV power line died of leukemia, which has recently been recognized as an occupational disease. Methods to reduce magnetic fields from power lines include shielding with wire loops, incorporating split phases and compaction techniques, installing underground power lines, converting to high-voltage direct current (HVDC), and increasing the ground clearance of transmission towers. Depending on whether a separate power supply is needed or not, there are two types of wire loops: passive loop and active loop. Magnetic field reduction is currently done through underground power lines; however, the disadvantage of this process is high construction costs. Installing passive loops, with relatively low construction costs, leads to lower magnetic field reduction rates than installing underground cables and a weakness to not solving the landscape problem. This methodological study aims at designing methods and reducing the effects of 2-wire set loops-the simplest and most practical. Since the method proposed in this study has been designed after analyzing the distribution of complex electromagnetic fields near the expected loop installation location, a practical design can be implemented without the need for any difficult optimization programming.

• KIEAE Journal
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• 제13권2호
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• pp.13-20
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• 2013

Today, the world energy consumption in buildings occupies more than 30%. In our country, the energy consumption in buildings also occupies 25% of the entire national energy consumption. With the increasing demand of energy saving in architectural fields, there is a more interest in low-energy construction. For these low-energy housings, our country is planning to apply the energy-saving design standards at the level of passive houses in 2017. However, there is still a limitation in energy saving only with the standards on the performance of envelope in buildings. This means that unless a building is airtight even though it was well-insulated, cooling and heating energy consumption will increase due to the infiltration and leakage. Therefore, this study aims to make a comparative analysis of airtight performance by conducting a blower door test on the housings applied with passive designs, analyze the reasons why most houses fall short of the airtightness standards, and complement the airtightness problems in the inadequate parts of the buildings in order to save building energy.

• 한국건축시공학회지
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• 제13권1호
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• pp.90-100
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• 2013

Deck-plates are widely used on construction sites, and have the advantage of enabling contractors to achieve a relatively uniform quality. But nevertheless, quality deviation in deck-plate construction can occur as the result of differences in site conditions and the experience of crew workers. In this study, the authors present a site quality evaluation prototype for building deck-plate construction. Through analyses of case studies and interviews with experts, standard quality check sheets and a quality management index were developed by estimating the importance of quality check items based on a Failure Mode and Effects Analysis (FMEA) method. The applicability and effectiveness of the prototype was evaluated through a case study and interviews with case participants. It was found that the prototype promoted an active quality management as a way of continuously improving quality management in deck-plate construction instead of passive quality inspection practice.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.121-122
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• 2023

Existing modular research has been mainly focused on S (shelter structure) and I (infill interior finishing material), and considerable research has been conducted, and the results are being proposed. However, in the case of the rest (exterior materials and windows, etc.), existing construction methods and materials are borrowed, and supporting hardware members and insulation materials are constructed on site, which acts as a factor hindering overall shortening of the construction period. That is, since the advantages and characteristics of modularity cannot be utilized in the absence of modular cladding, manufacturing of cladding is required. Therefore, it is necessary to develop a cladding system that can drastically reduce the construction period in factories while considering the structural characteristics of PC modulars.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.504-510
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• 2003

This study has been carried out to evaluate the passive treatment systems for acid mine drainage in Korea and to suggest, if possible, the method for the improvement. 35 passive treatment systems in 27 mines have been constructed since 1996. SAPS, being the main process, was combined with more than one of processes such as anaerobic wetland, aerobic wetland, and oxidation pond for the construction of passive treatment system. Problems observed during the operation include the poor sulfate removal ratio, overflow, leakage, unusabless of the whole system, and inefficiency. The reasons of the poor sulfate removal ratio are believed that the low temperature during the winter prohibits the SRB activity and HRT for bacterial sulfate reduction is insufficient. An alternative method In Adit Sulfate Reducing System which enables to keep the temperature constant at about $15^{\circ}C$ was suggested. IASRS is the methods of placing the SAPS inside the adit, which enables the temperature around the system constant can be maintained. The experiments using the laboratory scaled model systems made up of four sections showed high efficiencies in pH control and metal removal ratios, but showed still low sulfate removal ratio of about $23\%$ also with high COD at the beginning of the operation.