• Title/Summary/Keyword: snap-buckling

검색결과 44건 처리시간 0.018초

축대칭 하중을 받는 Hybrid 케이블 돔의 Bifurcation 특성에 관한 연구 (A Study on the Bifurcation Characteristics of Hybrid Cable Domes under Axisymmetric Load)

  • 김승덕;백인성;김형석
    • 한국전산구조공학회:학술대회논문집
    • /
    • 한국전산구조공학회 2003년도 가을 학술발표회 논문집
    • /
    • pp.277-284
    • /
    • 2003
  • One of important problem, in large space structure, is to overcome the self-weight of roof structure. This problem can be solved with using tension members effectively. Thus the rapid progress of hybrid structure, that makes effective use of the means of settling, has a good effect on realizing the large space. These systems of hybrid structure have the advantages of light weight and its own internal redundancy, but are occurred unstable phenomenon such as bifurcation or snap-through buckling, when the load level is come to the critical point. Among the hybrid structure, cable dome is shown the strong nonlinearity of unstable phenomenon in accordance with the external force. Therefore, the purpose of this study is to analyze and verify comparatively the unstable phenomenon of the Geiger and Flower type cable dome structures under axismmetric load.

  • PDF

송도 컨벤션 센터의 초기형상불완전 및 절점강성에 따른 좌굴하중 특성에 관한 연구 (A Study on Buckling Load Characteristic of Songdo Convention Center with Initial Imperfection and Joint Rigidity)

  • 문혜수;안상길;손수덕;이동우;김승덕
    • 한국공간구조학회:학술대회논문집
    • /
    • 한국공간구조학회 2006년도 춘계 학술발표회 논문집 제3권1호(통권3호)
    • /
    • pp.191-204
    • /
    • 2006
  • This paper investigate the optimum thickness distribution of plate structure with different essential boundary conditions in the fundamental natural frequency maximization problem. In this study, the fundamental natural frequency is considered as the objective function to be maximized and the initial volume of structures is used as the constraint function. The computer-aided geometric design (CAGD) such as Coon's patch representation is used to represent the thickness distribution of plates. A reliable degenerated shell finite element is adopted calculate the accurate fundamental natural frequency of the plates. Robust optimization algorithms implemented in the optimizer DoT are adopted to search optimum thickness values during the optimization iteration. Finally, the optimum thickness distribution with respect to different boundary condition

  • PDF

돔형 스페이스 프레임 구조물의 하중모드에 따른 분기점 특성에 관한 연구 (A Study on the Critical Point and Bifurcation According to Load Mode of Dome-Typed Space Frame Structures)

  • 손수덕;김승덕;이승재;김종식
    • 한국공간구조학회논문집
    • /
    • 제11권1호
    • /
    • pp.121-130
    • /
    • 2011
  • 스페이스 프레임 구조물은 연속체 쉘 구조물의 원리를 이용하여 매우 넓은 공간을 효과적 으로 덮을 수 있는 구조물이지만 뜀좌굴 및 분기좌굴 등과 같은 불안정거동은 돔형 구조물에서는 더욱 복잡하게 나타난다. 또한 붕괴메커니즘의 이론적 연구와 실험적 연구결과들 사이에서도 많은 차이를 보인다. 본 논문에서는 미적 효과가 크며 단층의 대공간을 확보하기에 적합한 돔형 공간 구조물의 구조 불안정 특성을 접선강성방정식을 이용하여 비선형 증분해석을 수행하고, Rise-span(${\mu}$)비 및 하중모드($R_L$)에 따른 임계점과 분기점의 특성을 돔형 공간구조물의 예제를 통해 고찰하였다. 여기서 불안정점은 증분해석과정을 통해서 예측할 수 있었으며, 예제에서 낮은 ${\mu}$에서는 전체좌굴이, 높은 ${\mu}$의 경우는 절점좌굴이 지배적이며, 낮은 $R_L$에서 정점좌굴이, 높은 $R_L$에서는 전체좌굴이 지배적이고, 전체좌굴이 나타나는 경우, 분기좌굴하중은 완전형상의 극한점좌굴하중의 약 50%에서 70%의 분포를 보였다.

매개 가진되는 얇은 외팔보의 비선형 진동 안정성 (Stability of Nonlinear Oscillations of a Thin Cantilever Beam Under Parametric Excitation)

  • 방동준;이계동;조한동;정태건
    • 한국소음진동공학회논문집
    • /
    • 제18권2호
    • /
    • pp.160-168
    • /
    • 2008
  • This paper presents the study on the stability of nonlinear oscillations of a thin cantilever beam subject to harmonic base excitation in vertical direction. Two partial differential governing equations under combined parametric and external excitations were derived and converted into two-degree-of-freedom ordinary differential Mathieu equations by using the Galerkin method. We used the method of multiple scales in order to analyze one-to-one combination resonance. From these, we could obtain the eigenvalue problem and analyze the stability of the system. From the thin cantilever experiment using foamax, we could observe the nonlinear modes of bending, twisting, sway, and snap-through buckling. In addition to qualitative information, the experiment using aluminum gave also the quantitative information for the stability of combination resonance of a thin cantilever beam under parametric excitation.