• 제목/요약/키워드: Floor diaphragm

검색결과 29건 처리시간 0.047초

가로리브와 U리브 용접부의 피로강도 향상을 위한 응력완화홀 (Relief Hole for Improvement of Fatigue Strength in Welded Intersections of Transverse and Longitudinal Ribs in Orthotropic Deck)

  • 정경섭;남승훈;양건봉;김경남
    • 한국강구조학회 논문집
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    • 제26권5호
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    • pp.419-430
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    • 2014
  • 연구대상인 강바닥판교의 U-리브와 가로리브를 교차하는 접합부에 대한 연구는 지속적으로 이루어지고 있으나 아직까지는 현재 적용되고 있는 스캘럽 자체 또는 내부의 다이아프램 형상을 개발 이용하고 있는 정도이다. 근본적으로 문제가 되고 있는 교차부 U-리브 하단 부위의 피로손상을 줄이기 위해, 본 연구를 통하여 제시된 SRH, 즉, U-리브가 교차하는 가로리브의 적절한 위치에 적합한 크기의 원형의 구멍을 두는 방안에 대하여 검토하였다. 최종적으로 원형 SRH가 강바닥판교의 U-리브와 가로리브 교차부 응력집중을 충분히 완화시킬 수 있음을 확인하였고, 이 부위의 구조상세의 피로손상을 방지할 수 있는 방안 중 하나로 SRH를 제안할 수 있었다.

척추 안정화를 위한 운동프로토콜 (The Exercise Protocol for Spinal Stabilization)

  • 김의룡;이건철
    • 대한물리치료과학회지
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    • 제15권4호
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    • pp.61-74
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    • 2008
  • Background: Purpose of this study is mat exercises and sling exercises that based on proceeding studies for exercising protocol for spinal stabilization. Methods: We analyze many other bibliographies and result of studies. Results: The vertebrae stabilization practices are formed on intra-abdominal pressure and converted into isolation of our body and limbs gradually through co-contraction training of transverse abdominis, pelvic floor muscle and diaphragm. Also, for prevention of low back pain and relapse, it is diverted to reflex muscle contraction training as well as functional integration. What is better, it should carry out with Activity of Daily Living. Conclusion: We should feel the necessity of it, more effective recognition training of local muscle for chronic low back pain patients. Besides, it is suggested that we should import measurable equipment and go hands with discipline.

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기둥 항복형 철골라멘의 복원력 특성 (Restoring Force Characteristics of Column Yield Type Steel Rahmen)

  • 윤명호
    • 한국디지털건축인테리어학회논문집
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    • 제4권2호
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    • pp.44-51
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    • 2004
  • It is generally known in seismic design that the beam yield type frames have more advantages than column yield type of which damage is likely to concentrate to any story. However we may design a building as a beam yield type, it becomes actually a column yield type collapse mode for slab floor diaphragm effect. Considering these points, the column yield type frames are selected and designed as the specimens. The object of this study is to grasp quantitatively the restoring force characteristic values and to estimate the seismic performances of column yield type steel rahmen.

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고층 튜브 구조물의 효율적 해석 (An Efficient Analysis of Framed-Tube Structures)

  • 이동근;김남희
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1992년도 가을 학술발표회 논문집
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    • pp.133-138
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    • 1992
  • The three dimensional analysis of Framed-Tube structures is neither easy nor efficient because of longer computational time, large memory requirement, tedious input preparation and bulky output. An efficient analysis model for framed-tube structure is proposed in this study. The proposed model can save the computational effort by using the assumption of the rigid floor diaphragm effect and matrix condensation technique. Moreover, it is develpoed by assembling two dimensional frames using the link degrees of freedom which are temporary used to satisfy the vertical displacement compatibility at the corners of a framed-tube. The accuracy and the efficiency of this analytical model is established by comparing with the results using the computer code SAPIV which is based on the three dimensional finite element model.

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비보강 조적조의 동적 거동 (Dynamic Response of Unreinforced Masonry Building)

  • 김남희;김재관
    • 한국지진공학회논문집
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    • 제8권5호통권39호
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    • pp.1-14
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    • 2004
  • 본 연구는 우리나라에서 저층 주거용 건물로 널리 사용되고 있는 2층 규모의 비보강조적조 의 1/3 축소 모델에 대한 진동대 실험을 수행한 것이다. 본 연구의 주목적은 내진설계가 이루어지지 않은 조적조 건물의 내진거동을 살펴보고, 실험적 자료를 확보하는데 있다. 실험대상구조물은 횡방향으로는 대칭이지만 종방향으로는 약간 비대칭이고, 비교적 강한 다이어프램을 나타내는 콘크리트 슬래브로 되어있다. 실험체에 대한 모의 지진하중은 가속도를 점차 증가시켜가면서 종방향으로 가력하였다. 실험에서 얻은 구조물의 동적 응답자료는 진동대의 입력지진과 연관지어서 분석하였다. 더욱이 성능기초설계를 위한 성능수준을 제시하였다. 실험결과 1층에서의 전단파괴가 지배적이고 상부층은 강체거동을 보여주었다. 또한 균열 발생후에도 상당한 강도와 변형능력을 보유하고 있는 것으로 나타났다.

Fragility reduction using passive response modification in a Consequence-Based Engineering (CBE) framework

  • Duenas-Osorio, Leonardo;Park, Joonam;Towashiraporn, Peeranan;Goodno, Barry J.;Frost, David;Craig, James I.;Bostrom, Ann
    • Structural Engineering and Mechanics
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    • 제17권3_4호
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    • pp.527-537
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    • 2004
  • Consequence-Based Engineering (CBE) is a new paradigm proposed by the Mid-America Earthquake Center (MAE) to guide evaluation and rehabilitation of building structures and networks in areas of low probability - high consequence earthquakes such as the central region of the U.S. The principal objective of CBE is to minimize consequences by prescribing appropriate intervention procedures for a broad range of structures and systems, in consultation with key decision makers. One possible intervention option for rehabilitating unreinforced masonry (URM) buildings, widely used for essential facilities in Mid-America, is passive energy dissipation (PED). After the CBE process is described, its application in the rehabilitation of vulnerable URM building construction in Mid-America is illustrated through the use of PED devices attached to flexible timber floor diaphragms. It is shown that PED's can be applied to URM buildings in situations where floor diaphragm flexibility can be controlled to reduce both out-of-plane and in-plane wall responses and damage. Reductions as high as 48% in roof displacement and acceleration can be achieved as demonstrated in studies reported below.

Analysis of a Building Structure with Added Viscoelastic Dampers

  • Lee, Dong-Guen;Hong, Sung-Il;Kim, Jin-Koo
    • 한국지진공학회논문집
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    • 제2권3호
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    • pp.27-35
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    • 1998
  • Steel structures with added viscoelastic dampers are analysed to investigat their behavior under earthquake excitation. The direct integration method, which produces exact solution for the non-proportional or non-classical damping system, is used throughout the analysis. The results from modal strain energy method are also provided for comparison. Then a new analytical a, pp.oach, based on the rigid floor diaphragm assumption and matrix condensation technique, is introduced, and the results are compared with those obtained from direct integration method and modal strain energy method. The well known phenomenon, that the effectiveness of the viscoelastic dampers depends greatly on the location of the dampers, is once again confirmed in the analysis. It is also found that the modal strain energy method generaly underestimates the responses obtained from the direct integration method, especially when the dampers are placed in only a part of the building. The proposed method turns out to be very efficient with considerable saving in computation this and reasonably accurate considering the reduced degrees of freedom.

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Seismic design of connections between steel outrigger beams and reinforced concrete walls

  • Deason, Jeremy T.;Tunc, Gokhan;Shahrooz, Bahram M.
    • Steel and Composite Structures
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    • 제1권3호
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    • pp.329-340
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    • 2001
  • Cyclic response of "shear" connections between steel outrigger beams and reinforced concrete core walls is presented in this paper. The connections investigated in this paper consisted of a shear tab welded onto a plate that was connected to the core walls through multiple headed studs. The experimental data from six specimens point to a capacity larger than the design value. However, the mode of failure was through pullout of the embedded plate, or fracture of the weld between the studs and plate. Such brittle modes of failure need to be avoided through proper design. A capacity design method based on dissipating the input energy through yielding and fracture of the shear tab was developed. This approach requires a good understanding of the expected capacity of headed studs under combined gravity shear and cyclic axial load (tension and compression). A model was developed and verified against test results from six specimens. A specimen designed based on the proposed design methodology performed very well, and the connection did not fail until shear tab fractured after extensive yielding. The proposed design method is recommended for design of outrigger beam-wall connections.

단순가력실험을 통한 콘크리트충전 강관기둥의 부착응력에 관한 연구 (An Experimental Study on the Bond Strengths for Concrete Filled Steel Tube Columns using a Push-Out Test)

  • 우해성;김진호;최성모
    • 한국강구조학회 논문집
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    • 제14권4호
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    • pp.481-487
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    • 2002
  • 콘크리트충전 강관기둥의 외다이아프램 접합부형식에서, 철골보의 하중이 내부의 콘크리트로 전달되는 하중전달 메카니즘이 아직 명확하게 규명되지 않았다. 여기서 각 층에서 철골보의 전단력은 외부의 강관과 내부의 콘크리트 사이의 부착응력에 의해 전달된다고 본다. 따라서 본 연구는 콘크리트충전 강관기둥의 부착응력을 파악하기 위해, 콘크리트면에만 하중을 가하는 단순가력실험을 실시하였다. 콘크리트 종류, 강관의 형상/길이, 이음부의 유무/뒷댐재의 두께 등을 변수로 총 30개의 실험체를 제작하여 실험을 실시했으며, 각 변수에 따른 실험결과를 비교/분석하고자 했다.