• Nuclear Engineering and Technology
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• 제31권6호
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• pp.586-594
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• 1999

To limit both the large displacement and acceleration response of the structure efficiently, the relationships between acceleration and displacement responses of the structure under several earthquakes are investigated for various horizontal stiffness of the base isolation system to determine the effective stiffness of the base isolation system in this paper. An example structure is a five-storey steel frame building as the primary structure and the secondary structures are assumed to be located on the fifth floor of the primary structure. Input motions used in the structural analysis are El Centre 1940, Taft 1952, Mexico 1985, San Fernando 1971 Pacoima Dam, and artificially generated earthquakes. The relationships of the absolute peak acceleration and the displacement at the top of the structure are calculated for various natural periods of base isolators under various earthquakes. The peak acceleration response of the fifth floor in the base isolated structure is significantly reduced by a factor of 2.1 through 6.25. Also, the relative displacement response of the floor to the base of the superstructure is very small. The results of this study can be utilized to determine the effective stiffness of the base isolation system.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 추계학술대회 논문집
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• pp.391-396
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• 2013

Psycho-acoustic experiments were carried out to know the inhabitant's response on floor impact noises due to floor structure types. The response values for tapping machine, bang machine and impact ball were 4.4~6.06. And children walking and adult walking were 1.67~2.97. Using 11 scale response tests, children and adult walking was not irritate to dwellers and children running was disturbing.

• 한국지진공학회논문집
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• 제17권6호
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• pp.279-291
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• 2013

The seismic damage of non-structural components, such as communication facilities, causes direct economic losses as well as indirect losses which result from social chaos occurring with downtime of communication and financial management network systems. The current Korean seismic code, KBC2009, prescribes the design criteria and requirements of non-structural components based on their elastic response. However, it is difficult for KBC to reflect the dynamic characteristics of structures where non-structural components exist. In this study, both linear and nonlinear time history analyses of structures with various analysis parameters were carried out and floor acceleration spectra obtained from analyses were compared with both ground acceleration spectra used for input records of the analyses and the design floor acceleration spectrum proposed by National Radio Research Agency. Also, this study investigates to find out the influence of structural dynamic characteristics on the floor acceleration spectra. The analysis results show that the acceleration amplification is observed due to the resonance phenomenon and such amplification increases with the increase of building heights and with the decrease of structure's energy dissipation capacities.

• 설비공학논문집
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• 제24권12호
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• pp.846-851
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• 2012

The radiant floor heating system is traditional heating system in korea. Radiant floor heating is small in vertical temperature difference, air stream and radiant heat distribution is uniform. And radiant floor heating system provide thermal comfort conditions to the a resident. This study was undertaken to evaluate the physiological-subjective responses of the resident's posture change such as sitting and standing. The experimental investigations were carried out in climate chamber, and subjects were 4 college-age students in good health. The physiological response was skin temperature and subjective response was undertaken survey of TSV and CSV. The results were summarized as follows; The comfortable temperature range of plantar surface was $35.1{\sim}38.9^{\circ}C$ and buttock surface was $37.8{\sim}39.3^{\circ}C$.

• 한국공간구조학회논문집
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• 제6권3호
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• pp.93-101
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• 2006

아파트의 온돌 바닥판은 콘크리트 바닥판위에 경량기포 모르타르, 완충재, 마감 모르터가 복층으로 시공되어 콘크리트 바닥판 상부의 시공방법 및 재료에 의한 구조적 거동에 대한 영향이 다르게 나타난다. 따라서 보다 합리적인 아파트의 콘크리트 적층 바닥판의 진동평가를 위해서는 시공방법 및 재료를 고려한 새로운 개선된 진동핵석 모델이 요구된다. 본 논문에서는 실제아파트의 적층으로 시공된 콘크리트 바닥판에 대한 보다 합리적인 진동해석 방법을 제안하고자 한다.

• Steel and Composite Structures
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• 제46권4호
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• pp.577-589
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• 2023

In this study, on-site testing was carried out to investigate the vibration performance of a cold-formed thin-walled steel floor system. Ambient vibration, walking excitation (single and double persons), and impulsive excitation (heel-drop and jumping) were considered to capture the primary vibration parameters (natural frequencies, damping ratios, and mode shapes) and vertical acceleration response. Meanwhile, to discuss the influence of cement fiberboard on structural vibration, the primary vibration parameters were compared between the systems with and without the installation of cement fiberboard. Based on the experimental analysis, the cold-formed thin-walled steel floor possesses high frequency (> 10 Hz) and damping (> 2%); the installed cement fiberboard mainly increases the mass of floor system without effectively increasing the floor stiffness and may reduce the effects of primary vibration parameters on acceleration response; and the human-structure interaction should be considered when analyzing the vibration serviceability. The comparison of the experimental results with those in the AISC Design Guide indicates that the cold-formed thin-walled steel floor exhibits acceptable vibration serviceability. A crest factor 𝛽_rp (ratio of peak to root-mean-square accelerations) is proposed to determine the root-mean-square acceleration for convenience.

• 국제초고층학회논문집
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• 제1권4호
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• pp.311-332
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• 2012

Earthquake response of mid-rise to high-rise buildings provided with friction dampers is investigated. The steel buildings are modelled as shear-type structures and the investigation involved modelling of the structures of varying heights ranging from five storeys to twenty storeys, in steps of five storeys, subjected to real earthquake ground motions. Three basic types of structures considered in the study are: moment resisting frame (MRF), braced frame (BF), and friction damper frame (FDF). Mathematical modelling of the friction dampers involved simulation of the two distinct phases namely, the stick phase and the slip phase. Dynamic time history analyses are carried out to study the variation of the top floor acceleration, top floor displacement, storey shear, and base-shear. Further, energy plots are obtained to investigate the energy dissipation by the friction dampers. It is seen that substantial earthquake response reduction is achieved with the provision of the friction dampers in the mid-rise and high-rise buildings. The provision of the friction dampers always reduces the base-shear. It is also seen from the fast Fourier transform (FFT) of the top floor acceleration that there is substantial reduction in the peak response; however, the higher frequency content in the response has increased. For the structures considered, the top floor displacements are lesser in the FDF than in the MRF; however, the top floor displacements are marginally larger in the FDF than in the BF.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.333-340
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• 2006

In these days the floor vibration is beginning to make its appearance of the environmental dispute in apartment building. Standard floor system are suggested for the settlement of this issue by government. The sound of floor impact sound is needed to secure comfortable quality in housing. Also, it is required an accurate analysis and a proper evaluation for floor vibration. Refine model is necessary for the floor system of housing to analyze accurately the floor vibration. But this refine model is not efficient because it is required so much running time for vibration analysis and it is difficult of modeling of standard floor slab. In this paper, new modeling methods of standard floor slab are proposed for the accurate rigidity evaluation. By using the new modeling method, the accurate vibration response can be obtained and can accurately evaluate the rigidity of standard floor system with resilient materials. Therefore the proposed modeling method is of practical use for vibration analysis of floor system of apartment building.

• 한국화재소방학회논문지
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• 제32권5호
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• pp.57-66
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• 2018

29명이 사망하고 40명이 부상을 입은 제천 스포츠센터 화재 사례에 대해 다수 사상자가 발생한 원인을 초기대응과 관리적인 측면을 중심으로 분석하였다. 초기대응 측면은 119신고 지연, 2층 세신사 비상구로 피난유도를 하지 않음, 1층과 3층 비상계단쪽 방화문 개방 상태 유지, 3층 주계단실 쪽 방화문 닫지 않음, 비상방송을 하지 않음으로 분석하였다. 관리적인 측면은 1층의 스프링클러설비 알람밸브 폐쇄, 소방펌프 제어반에서 기동 정지 위치에 놓음, 주차장 반자 안 누수 및 누전 방치, 2층 여탕의 휴게실 피난구유도등이 가려져 있고 비상구에 물건이 적치됨, 2층 자동문의 조작버튼 불량상태로 방치, 형식적인 소방안전관리, 소방시설 부실한 자체점검, 방화셔터와 배연창 미작동으로 분석하였다.

• 한국지진공학회논문집
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• 제12권1호
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• pp.57-66
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• 2008

본 연구에서는 원전 주제어실의 3차원 층 지진격리시스템에 대한 지진동 저감성능과 적용성을 평가하기 위해서 실험연구를 수행하였다. 3차원 층 지진격리시스템에 적용하기 위해서 마찰진자시스템과 에어 스프링을 설계하고 제작하였다. 제어 캐비닛과 액세스 플로어, 격자 프레임, 4개의 마찰진자와 에어 스프링으로 구성된 원전 주제어실 부분 실험모형을 2종류 제작하여 층 지진격리시스템의 원전 적용성을 평가하였다. 실험을 위해서 원전 주제어실의 운전기준지진(OBE)과 안전정지지진(SSE)의 수직방향, 수평방향 층 응답 스펙트럼을 이용하여 인공지진 시간이력을 만들어서 진동대 실험에 사용하였다. 입력지진에 대한 실험모형의 지진응답은 비 지진격리에 비해 3차원 층 지진격리시스템을 적용한 경우, 우수한 지진동 저감특성을 나타냈다