• Title/Summary/Keyword: Latticed beam

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A Case Study on Collapse and Reinforcement of Cut-slope in Gyeong-Nam Dae-Hap (경남 대합지구 절취사면의 붕괴 및 보강대책에 관한 사례연구)

  • Lee, Jin-Kwon;Park, Choon-Sik;Jang, Jeong-Wook
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.03a
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    • pp.703-710
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    • 2006
  • The objective of this study is to acquire stabilization of collapse of cut-slope in Chang-Nyung, Gyeong-Nam. The following shows the results of this study. We applied a reinforcement method with the latticed beam $(0.50\times0.50)$ + permanent anchor($PC\;6\times\phi12.7mm$, Ta = 50.0t/EA, etc 3.0m), and fill gravels(D=35cm) in the latticed beam. We attenuated the slope (1:2.0), and stabilized the slope pace by ASANA method. We planned a drainage way(U-type, $0.40\times0.40$) in order to prevent surface water from inflowing into underground.

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Nonlinear analysis of cable-stayed spatial latticed structures

  • Zhou, Dai;Liu, Hongyu;Jin, Bo
    • Structural Engineering and Mechanics
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    • v.15 no.4
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    • pp.415-436
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    • 2003
  • The combination of spatial latticed structures (hereafter SLS) and flexible cables, the cable-stayed spatial latticed structures (hereafter CSLS) can cross longer span. According to variation principle, a novel geometric nonlinear formulation for 3-D bar elements considering large displacement and infinitesimal rotation increments with second-order precision is developed. The cable nonlinearity is investigated and it is taken that the secant modulus method can be considered as an exact method for a cable member. The tower column with which the cables link is regarded as a special kind of beam element, and, a new simplified stiffness formulation is presented. The computational strategies for the nonlinear dynamic response of structures are given, and the ultimate load carrying capacities and seismic responses are analyzed numerically. It is noted that, compared with corresponding spatial latticed shells, the cable-stayed spatial latticed shells have more strength and more stiffness, and that the verical seismic responses of both CSLS and CLS are remarkably greater than the horizontal ones. In addition, the computation shows that the stiffness of tower column influences the performance of CSLS to a certain extent and the improvement of structural strength and stiffness of CSLS is relevant not only to cables but also to tower columns.

An Experimental Study on the Buckling & Behaviour of Single-Layer Latticed Dome (단층 래티스 돔의 좌굴 및 거동에 관한 실험적 연구)

  • Kim, Cheol-Hwan;Jung, Hwan-Mok
    • Journal of Korean Association for Spatial Structures
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    • v.6 no.4 s.22
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    • pp.35-44
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    • 2006
  • The form-resistant Systems like a dome and shell are used more widely than post-beam structure system in large space structure. Single layer latticed dome system, one of the form-resistant system, has great merits in manufacturing and constructing but the failure mechanism is not clarified yet. The purpose of this paper is to find out the buckling characteristics of single-layer latticed domes with square network by using the experimental method. Major test parameters are the stiffness of lattice member and space of square lattice. The specimens are applied uniform loading of snow type.

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Elasto-Plastic Buckling Analysis Based on the Slope-Deflection Method (처짐각법을 이용한 선형부재의 탄소성 좌굴해식)

  • Cheong, Myung-Chae
    • Journal of Korean Association for Spatial Structures
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    • v.6 no.4 s.22
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    • pp.63-72
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    • 2006
  • Fundamental equations of a member to analysis the elasto-plastic buckling analysis based on the deflection method are derived in this paper, and its validity and accuracy are shown by the numerical examples. The model discussing in the present paper has three elasto-plastic springs which are located at the both ends and center of a member and two elastic beam elements between them. The elasto-plastic springs represent the elasto-plastic behavior of the member and elastic beam element represents buckling behavior of the member. Numerical example shows the validity of this formulation.

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Fabrication of 2D Bravais Nano Pattern and Growth of ZnO Nano Rods with Photonic Crystal Effect (2차원 Bravais Lattice를 가지는 나노 패턴 제조 및 광결정 효과를 가지는 ZnO 나노 기둥 성장)

  • Kim, Tae-Un;Moon, Jong-Ha;Kim, Seon-Hoon;Kim, Doo-Gun;Kim, Jin-Hyeok
    • Korean Journal of Materials Research
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    • v.21 no.12
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    • pp.697-702
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    • 2011
  • Two-dimensional (2D) nano patterns including a two-dimensional Bravais lattice were fabricated by laser interference lithography using a two step exposure process. After the first exposure, the substrate itself was rotated by a certain angle, $90^{\circ}$ for a square or rectangular lattice, $75^{\circ}$ for an oblique lattice, and $60^{\circ}$ for a hexagonal lattice, and the $90^{\circ}$ and laser incident angle changed for rectangular and the $45^{\circ}$ and laser incident angle changed for a centered rectangular; we then carried out a second exposure process to form 2D bravais lattices. The band structure of five different 2D nano patterns was simulated by a beam propagation program. The presence of the band-gap effect was shown in an oblique and hexagonal structure. The oblique latticed ZnO nano-photonic crystal array had a pseudo-bandgap at a frequency of 0.337-0.375, 0.575-0.596 and 0.858-0.870. The hexagonal latticed ZnO nano-crystallite array had a pseudo-bandgap at a frequency of 0.335-0.384 and 0.585-0.645. The ZnO nano structure with an oblique and hexagonal structure was grown through the patterned opening window area by a hydrothermal method. The morphology of 2D nano patterns and ZnO nano structures were investigated by atomic force microscopy and scanning electron microscopy. The diameter of the opening window was approximately 250 nm. The height and width of ZnO nano-photonic crystals were 380 nm and 250 nm, respectively.