• 제목/요약/키워드: Geometrical Nonlinearity

검색결과 112건 처리시간 0.022초

케이블돔 구조물의 안정화 이행과정 및 구조적 거동특성에 관한 연구 (A Study on the Stabilizing Process and Structural Characteristics of Cable-Dome Structure)

  • 한상을;이경수;이주선;황보석
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1999년도 봄 학술발표회 논문집
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    • pp.260-267
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    • 1999
  • In this paper, We propose the initial shape finding and dynamic analysis of cable dome structure are presented. Cable dome that is consist of three component such as cable, strut and fabric membrane have complex structural characteristics. Main structural system of cable dome is cable-strut tensegric system, and fabric membrane element Is conceived as cladding roof material. One of the important problem of cable dome is shape finding of those subjected to cable and membrane forces, which stabilize the structures. And the other is structural response from external load effect such as snow and wind When cable dome are subjected to dynamic load such as wind load each structural component has many important problem because of their special structural characteristics. One problem is that geometrical nonlinearity should be considered in the dynamic analysis because large deformation is occurred from their flexible characteristic. The other problem is that wrinkling occurs occasionally because cable and membrane elements can not transmit compressive forces. So this paper describe the physical structural response of cable dome structure.

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Optimal design of double layer barrel vaults considering nonlinear behavior

  • Gholizadeh, Saeed;Gheyratmand, Changiz;Davoudi, Hamed
    • Structural Engineering and Mechanics
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    • 제58권6호
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    • pp.1109-1126
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    • 2016
  • The present paper focuses on size optimization of double layer barrel vaults considering nonlinear behavior. In order to tackle the optimization problem an improved colliding bodies optimization (ICBO) algorithm is proposed. The important task that should be achieved before optimization of structural systems is to determine the best form having the least cost. In this study, an attempt is done to find the best form then it is optimized considering linear and non-linear behaviors. In the optimization process based on nonlinear behavior, the geometrical and material nonlinearity effects are included. A large-scale double layer barrel vault is presented as the numerical example of this study and the obtained results indicate that the proposed ICBO has better computational performance compared with other algorithms.

바닥하중과 압축력을 받는 플랫 플레이트의 장기거동에 대한 해석적 연구 (Numerical Study on Long-term Behavior of Flat Plate Subjected to In-Plane Compressive and Transverse Loads)

  • 최경규;박홍근
    • 콘크리트학회논문집
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    • 제12권5호
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    • pp.153-164
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    • 2000
  • Numerical studies were carried out to investigate long-term behavior of flat plates, subjected to combined in-plane compressive and transverse loads. For the numerical studies, a computer program of nonlinear finite element analysis was developed. It can address creep and shrinkage as weel as geometrical and material nonlinearity, and also it can address various load combinations and loading sequences of transverse load, in-plane compressive load and time. This numerical method was verified by comparison with the existing experiments. Parametric studies were performed to investigate the strength variations of flat plates with four parameters; 1) loading sequence of floor load, compressive load and time 2) uniaxial and biaxial compression 3) the ratio of dead to live load 4) span length. Through the numerical studies, the behavioral characteristics of the flat plates and the governing load combinations were examined. These results will be used to develop a design procedure for the long-term behavior of flat plates in the future.

Topology optimization of nonlinear single layer domes by a new metaheuristic

  • Gholizadeh, Saeed;Barati, Hamed
    • Steel and Composite Structures
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    • 제16권6호
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    • pp.681-701
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    • 2014
  • The main aim of this study is to propose an efficient meta-heuristic algorithm for topology optimization of geometrically nonlinear single layer domes by serially integration of computational advantages of firefly algorithm (FA) and particle swarm optimization (PSO). During the optimization process, the optimum number of rings, the optimum height of crown and tubular section of the member groups are determined considering geometric nonlinear behaviour of the domes. In the proposed algorithm, termed as FA-PSO, in the first stage an optimization process is accomplished using FA to explore the design space then, in the second stage, a local search is performed using PSO around the best solution found by FA. The optimum designs obtained by the proposed algorithm are compared with those reported in the literature and it is demonstrated that the FA-PSO converges to better solutions spending less computational cost emphasizing on the efficiency of the proposed algorithm.

Nonlinear Aeroelastic Analysis of a High-Aspect-Ratio Wing with Large Deflection Effects

  • Kim, Kyung-Seok;Lim, In-Gyu;Lee , In;Yoo, Jae-Han
    • International Journal of Aeronautical and Space Sciences
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    • 제7권1호
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    • pp.99-105
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    • 2006
  • In this study, nonlinear static and dynamic aeroelastic analyses for a high-aspect-ratio wing have been performed. To achieve these aims, the transonic small disturbance (TSD) theory for the aerodynamic analysis and the large deflection beam theory considering a geometrical nonlinearity for the structural analysis are applied, respectively. For the coupling between fluid and structure, the transformation of a displacement from the structural mesh to the aerodynamic grid is performed by a shape function which is used for the finite element and the inverse transformation of force by work equivalent load method. To validate the current method, the present analysis results of a high-aspect-ratio wing are compared with the experimental results. Static deformations in the vertical and torsional directions caused by an angle of attack and gravity loading are compared with experimental results. Also, static and dynamic aeroelastic characteristics are investigated. The comparisons of the flutter speed and frequency between a linear and nonlinear analysis are presented.

충격하중을 받는 Euler기둥의 동적좌굴 해석 (Dynamic Instability Analysis of Euler Column under Impact Loading)

  • 김형열
    • 전산구조공학
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    • 제9권3호
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    • pp.187-197
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    • 1996
  • Explicit 직접적분법 알고리듬을 사용하여 Euler기둥의 동적 좌굴거동을 해석할 수 있는 수치해석법을 제시하였다. 평면뼈대 유한요소를 기하학적 비선형 거동과 전체좌굴의 영향을 고려할 수 있도록 보의 대변위 이론으로부터 유도하였고, central difference method를 바탕으로 해석 알고리듬을 개발하였다. 다양한 형상, 크기, 재하시간을 갖는 충격하중에 대하여 Euler기둥의 동적좌굴거동과 고유치 문제를 해석하였다. 수치해석 예제를 통하여 본 연구의 결과를 검증하였다.

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계류삭의 비선형운동특성해석에 관한 연구 (A Study on Nonlinear Analysis of Mooring Lines)

  • 이상무;김용철;김영환;홍석원;김훈철
    • 대한조선학회지
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    • 제23권1호
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    • pp.3-12
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    • 1986
  • This paper investigates the static configurations and the dynamic behaviors of a single point mooring line. To obtain the static configuration and static tension distribution along the mooring line, including the effect of fluid nonlinear drag and the elasticity of the line, the Runge-Kutta fourth order numerical method was used. The relationship between the horizontal excursion and the horizontal restoring force component of the mooring line, which is very important to a mooring line design, and the effect of a subsurface buoy on the static configuration are presented. In nonlinear dynamic analysis including nonlinear fluid drag acting on the line and geometrical nonlinearity for large deflections, finite element method using updated Lagrangian was used to obtain the solution. In the case of upper end harmonic excitation of the mooring line, the dynamic motion and the tension were also presented.

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케이블 돔의 구조적 거동 특성에 관한 연구 (A Study on the Structural Behavior of Cable Domes)

  • 한상을;윤종현;이승훈;진영상;황보석
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2000년도 가을 학술발표회논문집
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    • pp.151-158
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    • 2000
  • Cable dome that consists of three component such as cable, strut and fabric membrane has complex structural characteristics. Main structural system of cable dome is cable-strut tensegric system and fabric membrane element is conceived as cladding roof material. One of the important problem of cable dome is to investigate the structural response from external load effect such as snow and wind. When cable dome is subjected to load each structural component has various special structural characteristics. One is that geometrical nonlinearity should be considered because large deformation is occurred from their flexible characteristic. The other is that wrinkling occurs occasionally because cable and membrane elements can not transmit compressive forces. So this paper researches the physical structural response of cable dome structure and the structural behavior when failure occurred at a part of structure.

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Experimental and numerical analysis of composite beams strengthened by CFRP laminates in hogging moment region

  • El-Shihy, A.M.;Fawzy, H.M.;Mustafa, S.A.;El-Zohairy, A.A.
    • Steel and Composite Structures
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    • 제10권3호
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    • pp.281-295
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    • 2010
  • An experimental and a non linear finite element investigation on the behavior of steel-concrete composite beams stiffened in hogging moment region with Carbon Fiber Reinforced Plastics (CFRP) sheets is presented in this paper. A total of five specimens were tested under two-point loads. Three of the composite beams included concrete slab while the other two beams had composite slabs. The stiffening was achieved by attaching CFRP sheets to the concrete surface at the position of negative bending moment. The suggested CFRP sheets arrangement enhanced the overall beam behavior and increased the composite beam capacity. Valuable parametric study was conducted using a three dimensional finite element model using ANSYS program. Both geometrical and material nonlinearity were included. The studied parameters included CFRP sheet arrangement, concrete strength and degree of shear connection.

Geometrically nonlinear analysis of planar beam and frame structures made of functionally graded material

  • Nguyen, Dinh-Kien;Gan, Buntara S.;Trinh, Thanh-Huong
    • Structural Engineering and Mechanics
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    • 제49권6호
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    • pp.727-743
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    • 2014
  • Geometrically nonlinear analysis of planar beam and frame structures made of functionally graded material (FGM) by using the finite element method is presented. The material property of the structures is assumed to be graded in the thickness direction by a power law distribution. A nonlinear beam element based on Bernoulli beam theory, taking the shift of the neutral axis position into account, is formulated in the context of the co-rotational formulation. The nonlinear equilibrium equations are solved by using the incremental/iterative procedure in a combination with the arc-length control method. Numerical examples show that the formulated element is capable to give accurate results by using just several elements. The influence of the material inhomogeneity in the geometrically nonlinear behavior of the FGM beam and frame structures is examined and highlighted.