• 한국안전학회지
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• 제29권4호
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• pp.110-115
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• 2014

It is crucial for important facilities to withstand strong earthquakes because their damage may cause undesirable socio-economic effect. A liquefied natural gas (LNG) receiving terminal is one of the lifeline facilities whose seismic safety needs to be guaranteed. Even though all operating LNG receiving terminals in Korea were seismically designed, old design codes do not guarantee to comply with the current seismic design codes. In addition, if the constructional materials have been deteriorated, the seismic capacity of facilities may be also deteriorated. Therefore, it is necessary that the seismic performance of LNG receiving terminals is evaluated and the facilities that lack of seismic capacity have to be rehabilitated. In this paper, a procedure of seismic performance evaluation of such facilities is developed such that the procedure consists of three phases, namely pre-analysis, analysis, and evaluation phases. In the pre-analysis phase, design documents are reviewed and walk-on inspection is performed to determine the current state of the material properties. In the analysis phase, a structural analysis under a given earthquake or a seismic effect is performed to determine the seismic response of the structure. In the evaluation phase, seismic performance of the structure is evaluated based on limit states. Two of the important facilities, i.e. the submerged combustion vaporizer (SMV) and pipe racks of one of the Korean LNG receiving terminals are selected and evaluated according to the developed procedure. Both of the facilities are safe under the design level earthquake.

• 대한건축학회논문집:구조계
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• 제34권12호
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• pp.11-20
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• 2018

The purpose of this study is to investigate the seismic performance of exposed column-base plate strong-axis connections for small-sized steel buildings. Even though the seismic design for small-sized buildings became mandatory since Dec.2017, the arbitrary connection details in steel structure have been applied at the construction site, which is considered to be very insufficient to secure structural safety and stability considering the increased seismic risk. Therefore, a series of experimental test programs had been carried out to develop enhanced connection details in order to ensue the adequate seismic safety of small buildings. The hysteretic behavior of the exposed column-base plate connections commonly used in Korea seem to be very pure poor due to the "Rocking" phenomena between anchor plate and concrete by the residual plastic deformation of anchor bolts. A series of hysteretic tests were conducted to find the solution to overcome the "Rocking" phenomena of the exposed column-base plate connections, finally the stable seismic behavior was obtained by uisng at least 8 anchor bolts with good bonding strength to the protptype specimen.

• Structural Engineering and Mechanics
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• 제82권5호
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• pp.557-569
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• 2022

The retrofit of existing structures in high seismic zones is a crucial issue in the earthquake engineering field. The interest of the research community is particularly high for the structures that do not respect current seismic codes and present structural deficiencies such as poor detailing and lack of capacity design provisions. A reinforced concrete (RC) school building is used as case study to show the influence of different knowledge levels on the seismic retrofitting cost assessment. The safety assessment of the case study building highlights deficiencies under both vertical and seismic loads. By considering all the possible knowledge levels defined by the Italian such as by the European codes in order to derive the mechanical properties of the school building constitutive materials, the retrofit operations are designed to achieve different seismic safety thresholds. The retrofit structural costs are calculated and summed up to the costs for in-situ in tests. The paper shows how for the case study building the major costs spent for a large number of in-situ tests allows to save a consistent amount of money for retrofit operations. The hypothesis of demolition and reconstruction of the building is also compared in terms of costs with all the analyzed retrofit options.

• 한국안전학회지
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• 제24권2호
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• pp.55-61
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• 2009

Seismic Safety Analysis of Intake Tower is very important because failure of intake tower may incur huge chaos on the modem society. Recently, there has been growing much concern about earthquake resistance of existing structures. This research demonstrates the dynamic fluid pressure calculation using added mass simulation. The actual safety evaluation has been conducted through not only the static analysis but also the dynamic analysis. According to the analysis results, the vibration incurred by earthquake may induce considerable damage to the hydraulic structure. Therefore, the appropriate design process out of exact calculation is quite necessary.

• 한국안전학회지
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• 제28권4호
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• pp.97-102
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• 2013

This paper presents a new strengthening method of underground box structures against seismic loads for anti-seismic capacity improvement. A threaded steel member with pressure devices(so called 'I-bracing pressure system') is used to improve seismic capacity of the RC box structure. The I-bracing pressure system is fixed the corner of opening after chemical anchor was installed by drilling hole on the box structure. The structural performance was evaluated analytically. Two bracing types of strengthening methods were used; conventional bracing method and improved I-bracing pressure system. For the performance evaluation, seismic analyses were performed on moment and shear resisting structures with and without I-bracing pressure system. Numerical results confirmed that the proposed I-bracing pressure system can enhance the seismic capacity of the underground RC box structures.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1998년도 가을 학술발표회 논문집
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• pp.415-422
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• 1998

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.741-742
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• 2005

• Nuclear Engineering and Technology
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• 제31권6호
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• pp.66-82
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• 1999

The national long-term R&D program, updated in 1997, requires Korea Atomic Energy Research Institute(KAERI) to complete by the year 2006 the basic design of Korea Advanced Liquid Metal Reactor(KALIMER), along with supporting R&D work, with the capability of resolving the issue of spent fuel storage as well as with significantly enhanced safety. KALIMER is a 150 MWe pool-type sodium cooled prototype reactor that uses metallic fuel. The conceptual design is currently under way to establish a self-consistent design meeting a set of major safety design requirements for accident prevention. Some of the current emphasis includes those for inherent and passive means of negative reactivity insertion and decay heat removal, high shutdown reliability, prevention of and protection from sodium chemical reaction, and high seismic margin, among others. All of these requirements affect the reactor design significantly and involve extensive supporting R&D programs. This paper summarizes some of the results of conceptual engineering and design analyses performed for the safety of HAMMER in the area of inherent safety, passive decay heat removal, sodium water reaction, and seismic isolation.

• Nuclear Engineering and Technology
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• 제53권8호
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• pp.2716-2727
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• 2021

The core shroud is one of the most important internal components of the reactor vessel internals because it meets the neutron fluence directly emitted by the nuclear fuel. In particular, dynamic effects for an earthquake should be evaluated with respect to the neutron irradiation flux. As a prerequisite to this study, simplified and detailed finite element models are developed for the core shroud using the ANSYS Design Parametric Language. Using the El Centro earthquake, seismic analyses are performed for the simplified and detailed core shroud models. Modal characteristics are obtained and their results are used for a time history analysis. Response spectrum analyses are also performed to access the degree of seismic excitation. The results of these analyses are compared to investigate the response characteristics between the simplified and detailed core shroud models from the time history and response spectrum analyses.

• 한국방재안전학회논문집
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• 제13권3호
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• pp.1-14
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• 2020

본 연구는 국가산업단지 지진재난 안전관리 문제점 도출 및 개선방안 제시를 목적으로 수행되었다. 지진재난 안전관리 문제점을 조사하기 위하여 한국산업단지공단의 안전관리 운연현황 및 실무자 면담조사를 수행하였다. 또한, 전국 국가산업단지 28개소를 대상으로 내진설계 적용실태조사를 수행하였다. 상기 과정에서 도출된 문제점을 통합 정리한 후 전문가 의견 등을 반영하여 내진관련 법적규제 강화 등의 5가지 항목으로 분류된 개선방안을 제시하였다. 본 연구에서 제시한 개선방안은 향후 국가산업단지 내진성능 향상을 위한 정책수립 자료로 활용할 수 있을 것으로기대된다.