• 제목/요약/키워드: Special boundary

검색결과 352건 처리시간 0.024초

Improvement of a Requirement for Providing Special Boundary Element Considering Feature of Domestic High-rise Shear Walls

  • Kim, Taewan
    • Architectural research
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    • 제15권1호
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    • pp.43-52
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    • 2013
  • The reinforced concrete shear walls are being widely used in the domestic high-rise residential complex buildings. If designed by current codes, the special boundary element is needed in almost all high-rise shear wall buildings. This is because the equation for determining the provision of the special boundary element in the current codes cannot reflect the characteristics of the domestic high-rise shear walls with high axial load ratio and high proportion of elastic displacement to total displacement. In this study, a new equation to be able to reflect the characteristics is proposed. By using the equation, the special boundary element may not be necessary in certain cases so that structural engineers can relieve the burden of installing the special boundary element in every high-rise shear wall.

무차원 동영향 함수를 이용한 자유단 경계를 가진 임의 형상 평판의 자유진동해석 (Free Vibration Analysis of Arbitrarily Shaped Plates with Free Edges using Non-dimensional Dynamic Influence Functions)

  • 강상욱;김일순;이장무
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.740-745
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    • 2003
  • The so-called boundary node method (or NDIF method) that was developed by the authors has been extended for free vibration analysis of arbitrarily shaped plates with free edges. Since the proposed method is based on the collocation method, no integration procedure is needed on boundary edges of the plates and only a small amount of numerical calculation is required. A special coordinate transformation has been devised to consider the complicated free boundary conditions at boundary nodes. By the use of the special coordinate transformation, the radius of curvature involved in the free boundary conditions can be successfully dealt with. Finally, verification examples show that natural frequencies obtained by the present method agree well with those given by exact method and other analytical methods.

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경계요소의 횡보강근 상세를 개선한 RC 특수전단벽의 내진성능 평가 (Seismic Evaluation of RC Special Shear Wall with Improved Reinforcement Details in Boundary Elements)

  • 천영수
    • 토지주택연구
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    • 제3권2호
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    • pp.195-202
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    • 2012
  • 이 논문은 KBC2009에서 규정하고 있는 RC 특수전단벽과 시공성 개선을 목적으로 제안된 경계요소 내 완화된 배근상세를 갖는 특수전단벽과의 비교 실험결과를 제시하고 있다. 연구목적에 따라 22층 벽식구조 아파트로부터 모델링된 최하층 벽체가 2/3크기로 축소되어 2개의 실험체가 제작되었으며, 일정축력 하에서 반복가력 실험이 실시되었다. 실험결과, 완화된 배근상세를 따르는 특수전단벽체은 KBC2009의 배근상세를 따르는 특수전단벽체와 등가점성 감쇠비를 통해 계산된 에너지소산능력 및 연성도에서는 약간의 차이를 보이고 있으나, 하중-변위 측면에서는 매우 유사한 능력을 보이는 것으로 나타났다. 또한, 현행 설계기준에서 제시하고 있는 1.5% 수준의 층간횡변위비 조건을 충분히 만족하고 있음을 확인하였다.

특수 및 준특수 상세에 따른 철근콘크리트 전단벽의 내진성능평가 (Seismic Performance Evaluation of Reinforced Concrete Shear Wall Systems Designed with Special and Semi-Special Seismic Details)

  • 오해철;이기학;천영수;김태완
    • 한국지진공학회논문집
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    • 제18권4호
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    • pp.181-191
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    • 2014
  • This research presents the nonlinear analysis model for reinforced concrete shear wall systems with special boundary elements as proposed by the Korean Building Code (KBC, 2009). In order to verify the analysis model, analytical results were compared with the experimental results obtained from previous studies. Established analytical model was used to perform nonlinear static and dynamic analyses. Analytical results showed that the semi-special shear wall improved significantly the performance in terms of ductility and energy dissipation as expected based on previous test results. Furthermore, nonlinear incremental dynamic analysis was performed using 20 ground motions. Based on computer analytical results, the ordinary shear wall, special shear wall and newly proposed semi-special shear wall systems were evaluated based on the methods in FEMA P965. The results based on the probabilistic approaches accounting for inherent uncertainties showed that the semi-special shear wall systems provide a high capacity/demand (ACMR) ratio owing to their details, which provide enough capacity to sustain large inelastic deformations.

TWO EXAMPLES OF LEFSCHETZ FIXED POINT FORMULA WITH RESPECT TO SOME BOUNDARY CONDITIONS

  • Yoonweon Lee
    • 충청수학회지
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    • 제37권1호
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    • pp.1-17
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    • 2024
  • The boundary conditions $\tilde{P}_0$ and $\tilde{P}_1$ were introduced in [5] by using the Hodge decomposition on the de Rham complex. In [6] the Atiyah-Bott-Lefschetz type fixed point formulas were proved on a compact Riemannian manifold with boundary for some special type of smooth functions by using these two boundary conditions. In this paper we slightly extend the result of [6] and give two examples showing these fixed point theorems.

경계요소 횡보강근의 상세와 배근간격에 따른 특수전단벽의 내진성능 (Seismic Performance of Special Shear Wall with the Different Hoop Reinforcement Detail and Spacing in the Boundary Element)

  • 천영수
    • 토지주택연구
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    • 제6권1호
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    • pp.11-19
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    • 2015
  • 이 논문에서는 최근 강화된 내진규정에 의하여 현장에서 시공에 어려움을 겪고 있는 특수전단벽의 배근상세를 완화할 목적으로 제안된 경계요소 횡보강상세에 대하여 횡보강근의 형태와 배근간격에 따른 실험결과를 제시하고 있다. 실험결과, 제안된 횡보강 상세를 채용한 실험체의 균열 및 파괴양상은 폐쇄형 후프를 사용한 실험체와 유사한 경향을 나타내었으며, 최대강도도 예상값을 모두 상회하는 것으로 나타났다. 또한, 에너지 소산능력을 비교한 결과, 완화된 배근상세를 따르는 실험체(SSWR2)의 경우 기존 설계기준의 특수전단벽 실험체(SSW2)와 유사한 내진성능을 가지고 있는 것으로 나타났으며, 설계기준에서 제시하고 있는 1.5% 수준의 변형각 조건을 충분히 만족하고 있어 구조물의 주요 횡력저항 요소로서 사용될 수 있을 것으로 판단된다.

다양한 경계조건을 갖는 복합적층판의 정확한 고유진동수를 얻기 위한 간편 해석법 (A Simple Method of Obtaining "Exact" Values of the Natural Frequencies of Vibration for Some Composite Laminated Structures with Various Boundary Condition)

  • 김덕현;원치문;이정호
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2001년도 추계학술발표대회 논문집
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    • pp.9-12
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    • 2001
  • Composite materials can be used economically and efficiently in broad civil engineering applications when standards and processes for analysis, design, fabrication, construction and quality control are established. Many of the bridge systems, including the girders and cross-beams, and concrete decks behave as the special othotropic plates. Such systems with boundary conditions other than Navier or Levy solution types, or with irregular cross sections, analytical solution is very difficult to obtain. Numerical method for eigenvalue problems are also very much involved in seeking such a solution. A method of calculating the natural frequency corresponding to the first mode of vibration of beam and tower structures with irregular cross-sections was developed and reported by the author in 1974 Recently, this method was extended to two dimensional problems including composite laminates, and has been applied to composite plates with various boundary conditions with/without shear deformation effects and reported at several international conferences including the Eighth Structures Congress of American Society of Civil Engineers in 1990. In this paper, the result of application of this method to the special orthotropic plates with various boundary condition is presented.

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NOTES ON VANISHING THEOREMS ON RIEMANNIAN MANIFOLDS WITH BOUNDARY

  • Kitahara, Haruo;Pak, Hong-Kyung
    • 대한수학회지
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    • 제35권4호
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    • pp.831-841
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    • 1998
  • We shall discuss on some vanishing theorems of harmonic sections of a Riemannian vector bundle over a compact Riemannian manifold with boundary. In relating the results of H. Donnelly - P. Li ([4]), for special case of harmonic forms satisfying absolute or relative boundary problem, our results improve the vanishing results of T. Takahashi ([9]).

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SOLUTION OF THE BOUNDARY LAYER EQUATION FOR A MAGNETOHYDRODYNAMIC FLOW OF A PERFECTLY CONDUCTING FLUID

  • ZAKARIA, M.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제6권2호
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    • pp.63-73
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    • 2002
  • The influence of unsteady boundary layer magnetohydrodynamic flow with thermal relaxation of perfectly conducting fluid, past a semi-infinite plate, is considered. The governing non linear partial differential equations are solved using the method of successive approximations. This method is used to obtain the solution for the unsteady boundary layer magnetohydrodynamic flow in the special form when the free stream velocity exponentially depends on time. The effects of Alfven velocity $\alpha$ on the velocity is discussed, and illustrated graphically for the problem.

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BOUNDARY BEHAVIOR OF HOLOMORPHIC DISCS IN CONVEX FINITE TYPE DOMAINS

  • Lee, Kang-Hyurk
    • East Asian mathematical journal
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    • 제31권3호
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    • pp.351-356
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    • 2015
  • In this paper, we study holomorphic discs in a domain with a plurisubharmonic peak function at a boundary point. The aim is to describe boundary behavior of holomorphic discs in convex finite type domains in the complex Euclidean space in term of a special local neigh-borhood system at a boundary point.