• 제목/요약/키워드: collapse resistance

검색결과 202건 처리시간 0.026초

적외선분광법을 이용한 내화피복재 일치성 평가방법 연구 (A Study of Identification Test Method for Fire Resistive Paint in Near-Infrared Spectroscopy)

  • 조남욱;전수민;강성훈;인기호;이동호
    • 한국화재소방학회논문지
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    • 제24권3호
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    • pp.20-24
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    • 2010
  • 건축물의 화재발생 시 건축물 붕괴방지 및 인명의 피난시간 확보를 위하여 내화구조(내화피복재)를 시공하도록 하고 있으나 실제 규모와 가까운 내화시험의 특성으로 건축물 시공현장에서 내화구조(내화피복재)의 품질을 확인할 수 있는 현장품질방법이 부재하다. 따라서 근-적외선분광분석을 통하여 현장에서 적용할 수 있는 일치성 분석기법 연구를 통해 정확하고 간편한 과학적 내화구조현장관리 시험방법을 제시하고자 함.

Influence of ductility classes on seismic response of reinforced concrete structures

  • Nikolic, Zeljana;Zivaljica, Nikolina;Smoljanovic, Hrvoje
    • Coupled systems mechanics
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    • 제7권2호
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    • pp.177-195
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    • 2018
  • Reinforced concrete buildings in a seismically active area can be designed as DCM (medium ductility) or DCH (high ductility) class according to the regulations of Eurocode 8. In this paper, two RC buildings, one with a wall structural system and the other with a frame system, previously designed for DCM and DCH ductility, were analysed by using incremental dynamic analysis in order to study differences in the behaviour of structures between these ductility classes, especially the failure mechanism and ultimate collapse acceleration. Despite the fact that a higher behaviour factor of DCH structures influences lower seismic resistance, in comparison to DCM structures, a strict application of the design and detailing rules of Eurocode 8 in analysed examples caused that the seismic resistance of both frames does not significantly differ. The conclusions were derived for two buildings and do not necessarily apply to other RC structures. Further analysis could make a valuable contribution to the analysis of the behaviour of such buildings and decide between two ductility classes in everyday building design.

건물화재시 창문재료에 따른 내화특성 연구 (A Study on the Characteristics of Fire Resistance of Window Material in Compartment Fire)

  • 허만성;장문석;조수
    • 한국화재소방학회논문지
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    • 제17권1호
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    • pp.62-67
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    • 2003
  • 실제 건물화재에서 창문재료의 내화특성을 평가하기 위하여 건물화재실험이 수행되었다. 4 mx3.8mx2.4m 방에서 PVC 창문, 알루미늄 창문, AL+Wood 창문을 각각 설치하고 화원은 소파와 매트리스를 사용하였다. 창문은 아파트 베란다에 많이 사용하는 유리두께 6mm사이에 공기층 12 mm인 것을 사용하였다. 건물내부와 창문 주변의 온도분포를 살펴보기 위하여 총 32개 지점의 온도를 측정하였다. 실험결과 건물내의 온도분포, 창틀의 변화, 유리창의 파손 정도 둥을 조사하여 분석하였다.

코질환과 수면무호흡증 (Nasal Diseases and Its Impact on Sleep Apnea and Snoring)

  • 김창희;이재서
    • 수면정신생리
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    • 제11권1호
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    • pp.17-21
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    • 2004
  • Nasal congestion is one of the most common symptoms of medical complaints. Snoring is caused by vibration of the uvula and the soft palate. Nasal obstruction may contribute not only to snoring and obstructive sleep apnea (OSA) but also impair application of continuous nasal positive airway pressure (CPAP), which is the most widely employed treatment for OSA. Total or near-total nasal obstruction leads to mouth breathing and has been shown to cause increased airway resistance. However, the exact role of the nasal airway in the pathogenesis of OSA is not clear and there is no consensus about the role of nasal obstruction in snoring and sleep apnea. Some reports have failed to demonstrate any correlation between snoring and nasal obstruction. On the other hand, opposing reports suggest that nasal disease may cause sleep disorders and that snoring can be improved after nasoseptal surgery. Reduced cross-sectional area causes increased nasal resistance and predisposes the patient to inspiratory collapse of the oropharynx, hypopharynx, or both. Discrete abnormalities of the nasal airway, such as septal deformities, nasal polyps, and choanal atresia and with certain mucosal conditions such as sinusitis, allergic rhinitis and inferior turbinate hypertrophy can cause snoring or OSA. Thus, these sources of nasal obstruction should be corrected medically or surgically for the effective management of OSA and adjunctive for CPAP.

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현장실험을 통한 건식경량벽체의 부착물에 대한 하중 저항성 평가에 관한 연구 (A Study on the Evaluation of The Load Resistancy of Lightweight Wall against Wall Attachments through Field Tests)

  • 김태익;이주민;김상헌;최수경;서치호
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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    • pp.183-184
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    • 2015
  • Recent structural approach of the House of Commons has been an increase in demand for dry wall light due to a change in load bearing composite structure of a flat plate type structure under the name of long-life housing, attach the attachment to the wall as the needs of the residents of reserved space increases things that are on the rise. However, depending on the strength of collapse accidents is shown wall and recent wall deposits are required, a load resistance evaluation method of the deposit of the need is the situation. Therefore, in this study, for the evaluation of the evaluation of dry lightweight wall as widely used gypsum board and ALC lightweight wall of two types of laboratory the wall through the previous studies to be installed in direct co-housing to the target and field experiments I want to evaluate the different points.

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Nonlinear analysis based optimal design of double-layer grids using enhanced colliding bodies optimization method

  • Kaveh, A.;Moradveisi, M.
    • Structural Engineering and Mechanics
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    • 제58권3호
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    • pp.555-576
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    • 2016
  • In this paper an efficient approach is introduced for design and analysis of double-layer grids including both geometrical and material nonlinearities, while the results are compared with those considering material nonlinearity. Optimum design procedure based on Enhanced Colliding Bodies Optimization method (ECBO) is applied to optimal design of two commonly used configurations of double-layer grids. Two ranges of spans as small and big sizes with certain bays of equal length in two directions are considered for each type of square grids. ECBO algorithm obtains minimum weight grid through appropriate selection of tube sections available in AISC Load and Resistance Factor Design (LRFD). Strength constraints of AISC-LRFD specifications and displacement constraints are imposed on these grids.

Structural Behavior of Beam-Column Joints Consisting of Composite Structures

  • Lee, Seung-Jo;Park, Jung-Min;Kim, Wha-Jung
    • KCI Concrete Journal
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    • 제14권3호
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    • pp.111-120
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    • 2002
  • This study proposes a joint model consisting of different types of members as a new structural system, and then investigates the resulting structural behavior. The joint model consists of a concrete-filled steel tube column (CFT) together with a steel reinforced concrete at the end plus reinforced concrete beam at the center. For comparison, two other joint models were designed, that are, a CPT with a reinforced concrete beam, and a CFT with a steel reinforced concrete at the end plus steel concrete beam at the center, then their joint capacity and rigidity, energy absorption capacity, etc., were all investigated. From the results, the CFT column with a steel reinforced concrete at the end plus steel concrete beam at the center was outstanding in terms of its capacity and rigidity. The results of this analysis demonstrate that an adequate connection type and reinforcement method with different materials of increasing the rigidity, thereby producing a capacity improvement along with protection from pre-fractures.

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연료전지차량 차체프레임 강성 및 내구해석 (Stiffness and Fatigue Strength Analysis of Fuel Cell Vehicle Body Frame)

  • 최복록;강성종
    • 한국자동차공학회논문집
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    • 제19권4호
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    • pp.47-53
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    • 2011
  • Firstly, FEM model for the body frame of a fuel cell vehicle was built up and design optimization results based on different schemes were exhibited. One scheme was to minimize weight while maintaining the normal mode frequencies and the other was to increase the frequencies without weight change. Next, for a rear frame model, shape parameter study on collapse characteristics such as peak resistance load and absorbed energy was carried out. Also, the stiffness of frame mounting brackets was predicted using inertance calculation and the durability of those mounting brackets for vehicle system loads was evaluated. Finally, for a representative mounting model, the influence on durability due to thickness change was analyzed.

플랫 플레이트-기둥 접합부의 내진성능에 대한 해석연구 (Numerical Study on Seismic Resistance of Flat Plate-Column Connections)

  • 박홍근;최경규;황영현
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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    • pp.891-896
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    • 2002
  • Flat plate is susceptible to punching shear failure at the slab-column connection, which may cause catastrophic structural collapse. To prevent such brittle failure, strength and ductility of the connection should be ensured. However, since it is very difficult to experimentally simulate the actual load and boundary conditions of the flat plate system, it is not easy to obtain reliable information and data regarding to the strength and ductility of the flat plate-column connection. In the present study, numerical studies were performed for interior connections of continuous flat plate. The results were compared with the existing experiments, and the variations of bending moment, shear, torsional moment around the connection were investigated. Based on the findings of the numerical studies, the disadvantages of current design methods were discussed.

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공동주택 슬래브의 알루미늄 파이프서포트 개발에 관한 연구(I) (The Development of Aluminum Pipe Support for Apartment Slabs(I))

  • 차정구;이영섭
    • 한국안전학회지
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    • 제27권5호
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    • pp.105-110
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    • 2012
  • Steel elements are widely used for temporary structures on every construction site. but despite its strong resistences against heavy concrete volumes, they are easily eroded by oxygens in the space as times have been gone. If they are used several times in the construction fields, their elements are rusted and deformed and the strength is gradually reduced through the weak part. From this point of view, aluminum pipe support has been developed in stead of steel pipe sopport with enhancing durability against oxygens all the more. The developed aluminium pipe support has been lighter than steel unit, so workability has been improved. In another advantage of aluminium pipe support, different level control is possible with being equipped with the level control nut which enables the length adjustment of aluminium pipe support and the collapse of aluminum pipe support could be also prevented from the structures in the long term.