• Nuclear Engineering and Technology
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• 제48권4호
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• pp.881-892
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• 2016

Following the Fukushima accident and its extended station blackout, attention was brought to the importance of the spent fuel pools' (SFPs) behavior in case of a prolonged loss of the cooling system. Since then, many analytical works have been performed to estimate the timing of hypothetical fuel uncovery for various SFP types. Experimentally, however, little was done to investigate issues related to the formation of a flammable gas mixture, distribution, and stratification in the SFP building itself and to some extent assess the capability for the code to correctly predict it. This paper presents the main outcomes of the Experiments on Spent Fuel Pool (ESFP) project carried out under the auspices of Swissnuclear (Framework 2012-2013) in the PANDA facility at the Paul Scherrer Institut in Switzerland. It consists of an experimental investigation focused on hydrogen concentration build-up into a SFP building during a predefined scaled scenario for different venting positions. Tests follow a two-phase scenario. Initially steam is released to mimic the boiling of the pool followed by a helium/steam mixture release to simulate the deterioration of the oxidizing spent fuel. Results shows that while the SFP building would mainly be inerted by the presence of a high concentration of steam, the volume located below the level of the pool in adjacent rooms would maintain a high air content. The interface of the two-gas mixture presents the highest risk of flammability. Additionally, it was observed that the gas mixture could become stagnant leading locally to high hydrogen concentration while steam condenses. Overall, the experiments provide relevant information for the potentially hazardous gas distribution formed in the SFP building and hints on accident management and on eventual retrofitting measures to be implemented in the SFP building.

• 한국실내디자인학회논문집
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• 제23권1호
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• pp.69-77
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• 2014

This study aims to find the optimum method to reuse as townscape resource and to preserve the architectural heritage. And, it wants to contribute the policy of the architectural heritage and townscape. This research is targeted at an old office building of Leaf tobacco Producer' cooperation, designated as a cultural assets in Jecheon. It investigated the design characteristics of an old office building of Leaf tobacco Producer' cooperation and the streetscape of Uibyeong-daero 12-gil. It was conducted using the research methods of the field survey, and it was to analyze and to compare the various existing data and a current status. The result are as followings. Firstly, we should be consider the policy of architectural heritage that a sense of place can be preserved. Secondly, we should be consider the linear method of the conservation and reuse in urban street that the architectural heritage is located at least. Thirdly, if it will be to maintain the facade of the building adjacent to the street using the design characteristics of an old office building of Leaf tobacco Producer' cooperation, Uibyeong-daero 12-gil will be made a unique street that will be represented the history of leaf tobacco produce. Lastly, it has been analyzed that the design characteristics of an old office building of Leaf tobacco Producer' cooperation are the arch of entrance, the arched window, the rectangular window, the entabature, the horizontal joint, the finish of cement mortar, a pitched roof, etc. And, the design guideline and the maintenance plan of Uibyeong-daero 12-gil have made.

• Earthquakes and Structures
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• 제13권4호
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• pp.377-386
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• 2017

Earthquake-induced pounding damages to building structures were repeatedly observed in many previous major earthquakes. Extensive researches have been carried out in this field. Previous studies mainly focused on the regular shaped buildings and each building was normally simplified as a single-degree-of-freedom (SDOF) system or a multi-degree-of-freedom (MDOF) system by assuming the masses of the building lumped at the floor levels. The researches on the pounding responses between irregular asymmetric buildings are rare. For the asymmetric buildings subjected to earthquake loading, torsional vibration modes of the structures are excited, which in turn may significantly change the structural responses. Moreover, contact element was normally used to consider the pounding phenomenon in previous studies, which may result in inaccurate estimations of the structural responses since this method is based on the point-to-point pounding assumption with the predetermined pounding locations. In reality, poundings may take place between any locations. In other words, the pounding locations cannot be predefined. To more realistically consider the arbitrary poundings between asymmetric structures, detailed three-dimensional (3D) finite element models (FEM) and arbitrary pounding algorithm are necessary. This paper carries out numerical simulations on the pounding responses between a symmetric rectangular-shaped building and an asymmetric L-shaped building by using the explicit finite element code LS-DYNA. The detailed 3D FEMs are developed and arbitrary 3D pounding locations between these two buildings under bi-directional earthquake ground motions are investigated. Special attention is paid to the relative locations of two adjacent buildings. The influences of the left-and-right, fore-and-aft relative locations and separation gap between the two buildings on the pounding responses are systematically investigated.

• 대한건축학회논문집:계획계
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• 제34권6호
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• pp.3-14
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• 2018

The aim of this study is to propose a method for calculating the weight of walking energy in ERAM model by calculating it for the analysis of vertical and horizontal spaces in a building. Conventional theories on the space analysis in the field of architectural planning predict the pedestrian volume of network spaces in urban street or in two-dimensional plane within a building, however, for vertical and horizontal spaces in a building, estimates of the pedestrian volume by those theories are limited. Because in the spatial syntax and ERAM model have been applied weights such as the spatial depth, adjacent angles, and physical distances available only to the two-dimensional same layer or plane. Therefore, the following basic assumptions and analysis conditions in this study were established for deriving a predictor of pedestrian volume in vertical and horizontal spaces of a building. The basic premise of space analysis is not to address the relationship between the pedestrian volume and the spatial structure itself but to the properties of spatial structure connection that human beings experience. The analysis conditions in three-dimensional spaces are as follows : 1) Measurement units should be standardized on the same scale, and 2) The connection characteristics between spaces should influence the accessibility of human beings. In this regard, a factor of walking energy has the attributes to analyze the connection of vertical and horizontal spaces and satisfies the analysis conditions presented in this study. This study has two implications. First, this study has shown how to quantitatively calculate the walking energy after a factor of walking energy was derived to predict the pedestrian volume in vertical and horizontal spaces. Second, the method of calculating the walking energy can be applied to the weights of the ERAM model, which provided the theoretical basis for future studies to predict the pedestrian volume of vertical and horizontal spaces in a building.

• 한국환경복원기술학회지
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• 제11권6호
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• pp.49-60
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• 2008

In this study, the green zone patterns of sidewalks are classified 'one street-tree row + building,' 'one street-tree row + green zone,' 'two street-tree rows + building,' and 'two street-tree rows + green zone' and assessed their visual characteristic in order to provide desirable measures for scenery design. As a result of the analysis of visual images of sidewalk, the scenery in which street trees are planted in one row was generally assessed to be negative, while roads where green zones rather than buildings are adjacent were revealed to seem stable and pleasant. The scenery in which street trees are planted in two rows was assessed highly in an image of 'extensionality' indicating street circumstances, and especially the pattern 'two street-tree rows + green zone' was shown to be the most beautiful scenery. According to the results of factor analysis of sidewalks, three factors were identified : 'extensionality' showing sidewalk circumstances; 'peculiarity' including unique personality, and 'pliability' showing the organic flow of the scenery. The results of the analysis of visual preference of the scenery according to green zone patterns showed that the 'two street-tree rows + green zone' was measured to be highest. When buildings are adjacent to a sidewalk, two street-tree rows rather than one street-tree row were assessed to increase preference. As for the correlation between visual factors and preference analyzed through multiple regression analysis, all 'extensionality,' 'peculiarity,' and 'pliability' were revealed to show positive correlation for visual preference.

• 한국화재소방학회논문지
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• 제34권1호
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• pp.79-88
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• 2020

이 연구는 초고층건축물의 고층부에서 소방력의 공급의 효율성을 분석하고 이를 효율적으로 공급하는 방안을 제안하였다. 연구결과는 다음과 같다. 첫째, 화재감지는 외부에서 경보·진동·음성 등 화재경보의 다양화, 화재발생지점의 명확화 및 건축물 외부에도 화재층 표시를 통해 소방력 공급시간을 단축할 필요가 있다. 둘째, 신호통신은 무선통신보조설비의 설치대상을 강화하고, 중계기 설치를 보완하며, 다중통신망을 구성할 것을 제안하였다. 셋째, 행동결정은 인접건축물에서 도하의 방법으로 진압대원 및 소방장비를 공급하고, 일정 층마다 파괴가 용이한 유리창을 설치하며 식별표시도 필요하다. 넷째, 현장대응은 활강과 수직구조기법을 적용하여 소방장비의 공급 및 진압대원의 진입을 돕고 드론을 이용하여 소방장비를 공급한다. 마지막으로 충분한 소화액 제공은 헬리콥터와 인접한 건축물을 이용하여 소방용수를 공급한다.

• 한국지반환경공학회 논문집
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• 제13권10호
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• pp.85-94
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• 2012

최근의 건설공사는 개발사업의 증가와 국토의 효율적 개발에 의해 인접시설물과의 충분한 이격거리를 확보하지 못하고 공사를 진행하는 경우가 점차 증가하고 있다. 본 연구에서는 초고층빌딩 개발을 위한 지반 굴착공사와 철도시설 공사가 비슷한 시기에 수행된 지역에서 발생한 인접 철도시설물의 피해사례를 소개하고, 지층 특성과의 상호작용을 고려한 효율적인 보수 보강이 시행된 사례를 소개하고자 한다. 이를 위해 철도시설물 시공 시와 초고층빌딩 시공을 위한 굴착 공사 시 각종 현장조사 및 시험들이 수행되었으며, 이를 토대로 철도시설물과 선로의 침하 원인 분석이 시행되었다. 추가적으로 지반의 공극 충진을 통한 지반보강과 철도구조물의 침하복원을 위해 마이크로 시멘트를 적용한 보강 그라우팅 공법이 수행되었다.

• 한국터널지하공간학회 논문집
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• 제19권6호
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• pp.937-957
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• 2017

도심지 도로는 도시민의 안락한 편익을 제공하기 위해서 차량과 보행이 집중되고 각종 공급배관들이 매설되어 있으며 도시민은 도로에 접하고 있는 건축물을 주거, 사무, 상업, 휴게공간으로 이용하면서 안락한 생활을 영위하고 있다. 그러므로 높은 토지비용에도 불구하고 토지이용효율이 높은 지하건축물이 꾸준하게 건설되고 있다. 최근 지하건축물의 개착공사로 인해서 주변도로와 인접건물이 침하되는 등의 도시안전성 저해문제가 사회적으로 크게 이슈되고 있으며 이를 개선하기 위한 제도개선이 활발히 이루어지고 있다. 본 연구에서는 도심지 지하건축물의 지하굴착 안전성을 확보하고 주변 침하로 인한 민원을 효과적으로 예방할 수 있도록 새로운 형태의 강재주열벽을 개발하였으며 이를 이용한 지하건축물 가설공법에 관한 연구를 수행하였다. 또한 강재주열벽의 휨강도 시험을 통해서 강도설계법을 적용한 흙막이 벽체의 합리적인 설계방법을 제시하였다.

• 한국지진공학회논문집
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• 제1권1호
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• pp.79-88
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• 1997

주상복합건물의 강체거동을 보이는 연결층은 인접한 층에 비해 큰 질량과 강성차에 의해서 수치해석상의 문제점을 일으킨다. 강체거동을 보이는 구조물의 정적해석은 상부와 하부구조물을 별개의 구조물로 보고 2단계에 걸쳐서 근사적으로 수행될수 있지만, 동적해석은 구조물을 분리해서 행해질 수 없다. 이러한 주상복합건물의 동적해석을 위한 효율적인 모형화기법이 본 연구에서 제시된다. 자유도수를 줄여서 컴퓨터해석시간을 대폭 감소시키는 행렬의 응축기법과 연결층을 모형화하기 위해서 일반적인 보요소에 강체가 연결된 요소를 도입한다. 제안된 모형화기법의 효율성과 정확성을 입증하기 위해서 몇가지 구조해석을 한다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2002년도 학술대회지
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• pp.164-173
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• 2002

도심지 고층건축공사는 인접 건물과 도로에 의해 둘러 쌓여 있어 여유공간이 부족하고, 소음과 분진 등에 의한 문제가 발생한다. 이러한 문제들은 철저한 공사계획을 통해 여유공간을 효율적으로 활용하고, 공사 지원시설을 적절히 사용하는 가설계획을 통해 해결될 수 있다. 본 연구는 고층건축공사의 가설계획의 영향요소를 분석하고, 이를 활용한 가설계획의 대안 평가와 선정 방법을 제시하고 있다. 가설계획을 수립하는 과정에서 필요한 지식을 체계화하고 대안평가 방법을 적용하여 현장 관리자가 계획을 수립하는 과정을 지원할 수 있는 시스템을 구현하였다. 제안된 대안 평가 및 선정 방법과 구현된 시스템의 타당성을 검증하기 위해 사례 연구를 수행하였다.