• 제목/요약/키워드: Structural Stability

검색결과 2,683건 처리시간 0.034초

Structural behavior of aluminum reticulated shell structures considering semi-rigid and skin effect

  • Liu, Hongbo;Chen, Zhihua;Xu, Shuai;Bu, Yidu
    • Structural Engineering and Mechanics
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    • 제54권1호
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    • pp.121-133
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    • 2015
  • The aluminum dome has been widely used in natatorium, oil storage tank, power plant, coal, as well as other industrial buildings and structures. However, few research has focused on the structural behavior and design method of this dome. At present, most designs of aluminum alloy domes have referred to theories and methods of steel spatial structures. However, aluminum domes and steel domes have many differences, such as elasticity moduli, roof structures, and joint rigidities, which make the design and analysis method of steel spatial structures not fully suitable for aluminum alloy dome structures. In this study, a stability analysis method, which can consider structural imperfection, member initial curvature, semi-rigid joint, and skin effect, was presented and used to study the stability behavior of aluminum dome structures. In addition, some meaningful conclusions were obtained, which could be used in future designs and analyses of aluminum domes.

Optimal reinforcement design of structures under the buckling load using the homogenization design method

  • Min, Seungjae;Kikuchi, Noboru
    • Structural Engineering and Mechanics
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    • 제5권5호
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    • pp.565-576
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    • 1997
  • The material-based homogenization design method generates arbitrary topologies of initial structural design as well as reinforcement structural design by controlling the amount of material available. However, if a small volume constraint is specified in the design of Lightweight structures, thin and slender structures are usually obtained. For these structures stability becomes one of the most important requirements. Thus, to prevent overall buckling (that is, to increase stability), the objective of the design is to maximize the buckling load of a structure. In this paper, the buckling analysis is restricted to the linear buckling behavior of a structure. The global stability requirement is defined as a stiffness constraint, and determined by solving the eigenvalue problem. The optimality conditions to update the design variables are derived based on the sequential convex approximation method and the dual method. Illustrated examples are presented to validate the feasibility of this method in the design of structures.

Stabilities of cable-stiffened cylindrical single-layer latticed shells

  • Li, Pengcheng;Wu, Minger
    • Steel and Composite Structures
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    • 제24권5호
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    • pp.591-602
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    • 2017
  • A cable-stiffened cylindrical single-layer latticed shell that is reinforced by cable-stiffened system has superior stability behaviour compared with the ordinary cylindrical latticed shell. The layouts of cable-stiffened system are flexible in this structural system, and different layouts contribute different stiffness to the structure. However, the existed few research primarily focused on the simplest type of cable layouts, in which the grids of the latticed shell are diagonally stiffened by prestressed cables in-plane. This current work examines the stability behaviour of the cable-stiffened cylindrical latticed shells with two different types of cable layouts using nonlinear finite element analysis. A parametric study on the effect of cross-sectional of the cables, pretension in cables, joint stiffness, initial imperfections, load distributions and boundary conditions is presented. The findings are useful for the reference of the designer in using this type of structural system.

초음속 비행체 모델의 연성기법을 이용한 구조 안전성 해석 (An analysis on the Structural Safety of Supersonic rocket Preliminary Model using Fluid-Structure Interaction)

  • 도규성;소정수;강지훈;김형진;박대훈;오정수;문희장
    • 항공우주시스템공학회지
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    • 제2권2호
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    • pp.35-41
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    • 2008
  • The structural stability for preliminary model of supersonic rocket which has large L/D ratio is investigated. Large L/D ratio can cause a critical problem on the structural stability by the increase of bending-moment. By using the ANSYS and the CFX codes, we inspected the structural stability for Ma=2 and angle of attack for $20^{\circ}$. The optimum number of bolts and their joints required on the rocket surface are predicted.

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산업용 교반기 임펠러의 형상에 따른 구조 안정성 평가 (Structural Stability Evaluation on the shape of impeller for Industrial agitator)

  • 김기선;임태양
    • 한국산학기술학회논문지
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    • 제12권2호
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    • pp.611-616
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    • 2011
  • 본 논문은 산업 전반에 걸쳐 널리 사용되는 교반기에서 기계동력을 교반에너지로 바꾸어 주는 임펠러에 대해 연구이다. 기존 제품과 새로 제안한 두 가지 형상의 모델에 대한 구조해석 및 고유진동수, 진동 조화 해석을 수행함으로써 임펠러의 형상에 따라 국부적 응력 집중되는 취약부위에 대한 분석과 설계를 확인함으로써 임펠러의 형상에 따른 구조적 안정성을 평가하였다.

터널 굴착기 유압시스템용 유량 제어 블록 개발 (Development of Flow Control Block for Hydraulic System of Tunnel Boring Machine)

  • 이재동;임상진
    • 한국기계기술학회지
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    • 제20권6호
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    • pp.929-935
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    • 2018
  • This paper develops a flow control block for a hydraulic system of a tunnel boring machine. The flow control block is a necessary component to ensure stability in the operation of the hydraulic system. In order to know the pressure distribution of the flow control block, the flow analysis was performed using the ANSYS-CFX. It was confirmed that the pressure and flow rate were normally supplied to the hydraulic system even if one of the four ports of the flow control block was not operated. In order to evaluate the structural stability of the flow control block, structural analysis was performed using the ANSYS WORKBENCH. As a result, the safety factor of the flow control block is 1.54 and the structural stability is secured.

취약계층을 위한 개인 이동체 개발 연구 (A Study on the Development of Personal Mobility for the Vulnerable Group)

  • 한광호;이철희
    • 드라이브 ㆍ 컨트롤
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    • 제18권4호
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    • pp.35-42
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    • 2021
  • A personal mobility withstanding function for the disabled and vulnerable groups with difficulties in mobility was developed and structural and dynamics analysis was conducted. Personal mobility devices are a very helpful means of transportation for the disabled and vulnerable groups. In addition, the standing function allows individuals to perform a difficult task in while seated and offers a medical advantage to the user. In this study, a personal mobility device was designed and developed to help vulnerable groups and disabled people overcome limited mobility, and communicate with the general people at eye level through standing functions. Through structural and dynamic analysis, the structural safety, optimal speed during rotation, and lateral acceleration of the personal mobility device was analyzed. The analysis results are expected to contribute to the improvement of the users' convenience and stability of personal mobility.

Structural Design on Joint Component of Composite Wing of WIG Craft

  • Lee, Younggyu;Park, Hyunbum
    • International Journal of Aerospace System Engineering
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    • 제8권2호
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    • pp.1-3
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    • 2021
  • This study proposed a specific preliminary structural design procedure of the main wing for a small scale WIG vehicle to meet the target weight of the system requirement. The high stiffness and strength Carbon-Epoxy material was used for lightness, and the foam sandwich type structure at the upper skin and the spar webs was adopted for improvement of structural stability. After structural design, wing joint part was designed. Through investigation on structural design result, design modification was performed. After design modification, even thought the designed wing weight was a little bit heavier than the target wing weight, the structural safety and stability of the final design feature was confirmed.