• Title/Summary/Keyword: dome

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Analysis of stability on steel D&I can (Steel D&I Can의 안정성 해석)

  • Cho, S.J.;You, C.S.;Jung, S.W.;Park, H.C.;Hwang, W.;Han, K.S.
    • Proceedings of the KSME Conference
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    • 2001.11a
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    • pp.471-476
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    • 2001
  • The main object of this study is to develop a reliable FEM simulation technique for stability test using ABAQUS software and to clarify the effect of base profile of a steel D&I(drawn and ironed) can on the dome reversal pressure. For the can after body making simulation, two kind of stability test, dome buckle test and axial crush test are performed. The factors studied in the base profile on the dome reversal pressure are the base diameter, the rim radius, the dome shoulder radius, the dome radius and the dome depth. Within the limits before the occurrence of normal snap-through buckling of dome, the dome reversal pressure is improved by decreasing the base diameter, increasing the dome depth or increasing the dome shoulder depth.

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Structural behavior of the suspen-dome structures and the cable dome structures with sliding cable joints

  • Liu, Hongbo;Chen, Zhihua
    • Structural Engineering and Mechanics
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    • v.43 no.1
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    • pp.53-70
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    • 2012
  • Sliding cable joints have been developed for the cable dome structures and the suspen-dome structures to reduce the cable pre-stressing loss and obtain a uniform inner force in each hoop cable. However, the relevant investigation is less addressed on the structural behavior of the cable dome structures and the suspen-dome structures with sliding cable joints due to the lack of analysis techniques. In this paper, a closed sliding polygonal cable element was established to analyze the structural behavior of the cable dome structures and the suspen-dome structures with sliding cable joints. The structural behaviors with sliding cable joints were obtained.

Modeling of the triangle optimum shape in the surface of an Aluminum dome structure (알루미늄 돔 구조물에서 표면의 삼각형 최적 형상 모델링)

  • 이성철;조종두
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1997.10a
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    • pp.647-650
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    • 1997
  • A complete dome structure is based on a basic dome modeling, and the basic dome modeling affects safety of the dome structure. In other to save the manufacture expenses, an optimum shape modeling of a dome structure is necessary work of before manufacture of the dome. In this study, modeling of the triangle optimum shape in the surface of an aluminum dome is more focused to optimize shape of the dome and save manufacture expenses. After being made the systematic procedure of the basic modeling, the programming work of the procedure is performed. The program is made by C language, and the trust of the program is proved by comparison between output data of the program and basic modeling in PATRAN.

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Impact Analysis for Sonar Domes Collided with Logs (수중 부유물에 의한 소나돔 충격해석)

  • Kang, Myung-Hwan
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.4
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    • pp.564-571
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    • 2011
  • During navigation of warships, sonar domes have been damaged by collision with floating objects like logs. In order to analyze the damage of a sonar dome from collisions with a log, The analytical method and the numerical analysis using ABAQUS are performed. Throughout the analytical method, the mechanism of collision between a sonar dome and log is analyzed. To design a sonar dome, the numerical analysis for A type sonar dome and the B type sonar dome have done considering fluid loading effect around the sonar domes with normal and maximum speeds of the ship, respectively. The numerical analysis results of the A type sonar dome and the B type sonar dome are compared and analyzed.

Air dome inner pressure control system

  • Miki, Norihisa
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.727-730
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    • 1989
  • Tokyo dome is Japan's first air dome. The roof of the dome is supported by air pressure. The centralized control system (YOKOGAWA's DCS : CENTUM and YEWPACK) is applied to automatically regurate the air pressure. The control system acquires signals from sensors positioned throughout the stadium and operate 36 fans to blow air into the dome. Great emphasis is placed on the reliability and safety of the system.

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Multiobjective size and topolgy optimization of dome structures

  • Tugrul, Talaslioglu
    • Structural Engineering and Mechanics
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    • v.43 no.6
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    • pp.795-821
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    • 2012
  • The size and topology of geometrically nonlinear dome structures are optimized thereby minimizing both its entire weight & joint (node) displacements and maximizing load-carrying capacity. Design constraints are implemented from provisions of American Petroleum Institute specification (API RP2A-LRFD). In accordance with the proposed design constraints, the member responses computed by use of arc-length technique as a nonlinear structural analysis method are checked at each load increment. Thus, a penalization process utilized for inclusion of unfeasible designations to genetic search is correspondingly neglected. In order to solve this complex design optimization problem with multiple objective functions, Non-dominated Sorting Genetic Algorithm II (NSGA II) approach is employed as a multi-objective optimization tool. Furthermore, the flexibility of proposed optimization is enhanced thereby integrating an automatic dome generating tool. Thus, it is possible to generate three distinct sphere-shaped dome configurations with varying topologies. It is demonstrated that the inclusion of brace (diagonal) members into the geometrical configuration of dome structure provides a weight-saving dome designation with higher load-carrying capacity. The proposed optimization approach is recommended for the design optimization of geometrically nonlinear dome structures.

RESEARCH ON LOAD-BEARING PROPERTY AND DESIGN OF CABLE DOMES

  • Shen Cao;Zi Zhu
    • International conference on construction engineering and project management
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    • 2005.10a
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    • pp.596-605
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    • 2005
  • The cable dome, proposed by Geiger after developing Fuller's idea of tensegrity and improved by Levy, is a new type of large span space structures. In this paper, formulations of the initial forces distribution in members of two main systems of cable dome, which are Geiger dome and Levy dome, are presented. By analyzing the static performance of Levy dome and the variation of internal forces in members of the structure, four groups of design parameters in cable dome structure are represented in terms of: (1) the numbers of rings and the spaces between the rings; (2) the slopes of ridge cables; (3) the lengths of struts; (4) the initial force in one member of the structure.

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Optimum topology design of geometrically nonlinear suspended domes using ECBO

  • Kaveh, A.;Rezaei, M.
    • Structural Engineering and Mechanics
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    • v.56 no.4
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    • pp.667-694
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    • 2015
  • The suspended dome system is a new structural form that has become popular in the construction of long-span roof structures. Suspended dome is a kind of new pre-stressed space grid structure that has complex mechanical characteristics. In this paper, an optimum topology design algorithm is performed using the enhanced colliding bodies optimization (ECBO) method. The length of the strut, the cable initial strain, the cross-sectional area of the cables and the cross-sectional size of steel elements are adopted as design variables and the minimum volume of each dome is taken as the objective function. The topology optimization on lamella dome is performed by considering the type of the joint connections to determine the optimum number of rings, the optimum number of joints in each ring, the optimum height of crown and tubular sections of these domes. A simple procedure is provided to determine the configuration of the dome. This procedure includes calculating the joint coordinates and steel elements and cables constructions. The design constraints are implemented according to the provision of LRFD-AISC (Load and Resistance Factor Design-American Institute of Steel Constitution). This paper explores the efficiency of lamella dome with pin-joint and rigid-joint connections and compares them to investigate the performance of these domes under wind (according to the ASCE 7-05), dead and snow loading conditions. Then, a suspended dome with pin-joint single-layer reticulated shell and a suspended dome with rigid-joint single-layer reticulated shell are discussed. Optimization is performed via ECBO algorithm to demonstrate the effectiveness and robustness of the ECBO in creating optimal design for suspended domes.

A comparison of the forces on dome and prism for straight and tornadic wind using CFD model

  • Yousef, Majdi A.A.;Selvam, Panneer R.;Prakash, Jai
    • Wind and Structures
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    • v.26 no.6
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    • pp.369-382
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    • 2018
  • Tornadoes are vertical swirling air formed because of the existence of layers of air with contrasting features of temperature, wind flow, moisture, and density. Tornadoes induce completely different wind forces than a straight-line (SL) wind. A suitably designed building for an SL wind may fail when exposed to a tornado-wind of the same wind speed. It is necessary to design buildings that are more resistant to tornadoes. In tornado-damaged areas, dome buildings seem to have less damage. As a dome structure is naturally wind resistant, domes have been used in back yards, as single family homes, as in-law quarters, man caves, game rooms, storm shelters, etc. However, little attention has been paid to the tornadic wind interactions with dome buildings. In this work, the tornado forces on a dome are computed using Computational Fluid Dynamics (CFD) for tornadic and SL wind. Then, the interaction of a tornado with a dome and a prism building are compared and analyzed. This work describes the results of the tornado wind effect on dome and prism buildings. The conclusions drawn from this study are illustrated in visualizations. The tornado force coefficients on a dome building are larger than SL wind forces, about 120% more in x- and y-directions and 280% more in z-direction. The tornado maximum pressure coefficients are also higher than SL wind by 150%. The tornado force coefficients on the prism are larger than the forces on the dome, about 100% more in x- and y-directions, and about 180% more in z-direction. The tornado maximum pressure coefficients on prism also are greater those on dome by 150% more. Hence, a dome building has less tornadic load than a prism because of its aerodynamic shape.

Wind Pressure Spectra for Circular Closed and Open Dome Roofs (원형 밀폐 및 개방형 돔 지붕의 풍압 스펙트럼)

  • Cheon, Dong-jin;Kim, Yong-Chul;Lee, Jong-Ho;Yoon, Sung-Won
    • Journal of Korean Association for Spatial Structures
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    • v.20 no.2
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    • pp.69-76
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    • 2020
  • Wind tunnel tests were conducted to analyze the wind fluctuating pressures on a circular closed and open dome roof with a low span rise. Two dome models with various geometric parameters (height/span ratios and open ratios) were used for fixed span rise ratio dome and wind pressure spectrum were analyzed. The applicability was examined in comparison with the spectral model proposed in the previous studies. The analysis results show that the wind pressure spectrum of open dome roof tends to increase power in the high frequency range and the second peak is found in the area different from the closed dome roof. In addition, according to the comparison analysis with the previous proposed spectral model, it was found that it is not applicable to the closed and open dome roofs with low rise ratio due to the different peak frequencies.