• Title/Summary/Keyword: 좌굴하중 평가

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Analysis of Compression Characteristics of the Steel Plate-Concrete Wall Structures with Openings (개구부가 있는 강판콘크리트 벽체의 압축특성 분석)

  • Choi, Byong-Jeong
    • Journal of Korean Society of Steel Construction
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    • v.24 no.3
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    • pp.245-256
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    • 2012
  • The objective of this study is to investigate the effect of the openings on the structural behavior of SC walls. The test parameters were with or without the reinforcing of openings and sleeve thickness. The common failure showed that the crack in the concrete progressed with the plate's local buckling between the shear connectors. The failure of the openings showed that the vertical wall of the sleeve buckled toward the opening inside. The plate buckling load showed a similar value with or without the sleeve of the opening, respectively. However, the maximum compressive strength of the specimen without the opening was higher than that of specimen with the opening.

Stability of Moment Resisting Steel Frames with Weak Beams (보항복형 강구조골조의 안정성에 관한 연구)

  • Shin, Yong Woo;Kim, Hee Dong;Lee, Myung Jae
    • Journal of Korean Society of Steel Construction
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    • v.10 no.2 s.35
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    • pp.253-261
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    • 1998
  • The buckling length of exterior beam-columns of the first floor in moment resisting steel frames with weak beams is uncertain when plastic hinges occur at the ends of weak beams due to seismic loads. The objective of this study is to investigate the buckling strength of concrete-filled tubular beam-columns and to suggest the reduced buckling length of them to apply to the beam-column design code. The exterior beam-columns are modelized with horizontal displacement restraint springs. Their strength and reduced buckling length are evaluated by numerical analysis.

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A Study on Capacity Evaluation for Singly Symmetric Stepped Beam with Pure Bending (순수 휨하중 받는 일축대칭 스텝보의 성능평가기법에 관한 연구)

  • Oh, Jeong-Jae;Kim, Yong-Hee;Park, Jong-Sub;Oh, Byung-Sam
    • Proceedings of the KAIS Fall Conference
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    • 2008.11a
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    • pp.105-108
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    • 2008
  • 본 연구에서는 기존에 수행된 균일단면을 가지는 I형 보의 좌굴 강도에 대한 해석적?이론적 연구를 토대로 일축대칭을 이루는 변단면 I형보의 좌굴강도를 산정하고자 범용구조해석프로그램 ABAQUS (2007)를 이용하여 유한요소해석을 실시하였다. 유한요소해석에는 4절점 쉘요소인 S4R이 사용되었고, 플랜지 길이방향 비, 너비방향 비, 두께의 비로 일축대칭 스텝보를 사용하였으며, 균일모멘트를 작용시켰다. 개발된 좌굴강도 제안식은 해석결과와 비교하여 -11%~2%의 오차범위를 나타내었다. 본 연구결과는 다양한 형식의 일축대칭 I형보가 사용되는 빌딩 및 교량 구조물의 경제적이고 합리적인 설계에 활용 될 수 있을 것이다.

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Manbridge Crane의 지진해석에 관한 연구

  • 윤정방;박창호
    • Computational Structural Engineering
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    • v.4 no.4
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    • pp.24-28
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    • 1991
  • 본 연구용역에서는 반도기계주식회사의 의뢰에 의거하여 Manbridge Crane의 지진하중에 대한 구조물의 안전성을 평가하였다. 구조해석은 유한요소 모형을 사용하여 사하중, 활하중 및 OBE(Operating Basis Earthquake)와 SSE(Safe Shut-down Earthquake)의 지진하중에 관한 해석을 수행하였다. Crane설치지점의 층응답스펙트럼을 입력으로 한 응답스펙트럼해법으로 지진해석을 수행하였다. Trolley의 위치와 정격하중의 유무에 따라서 5개의 구조모형을 작성하여 해석을 수행하였으며, 지진해석에는 35개의 자유진동모드가 고려되었다. 구조해석을 통하여 1) 구조부재의 과도응력 발생여부, 2) 보강재의 좌굴 가능성, 3) Hoist Rope의 안전성, 4) Crane의 전도의 가능성 및 Seismic Lug의 안전성, 5) 지진하중에 대한 제동력, 6) Crane의 주행 Rail로부터의 탈선여부, 7) Traversing Rail의 수직처짐, 8) 주행 Rail 및 End Stopper의 Anchor Bolt의 안정성, 9) Fuel Basket과 Handrail의 안전성을 검토하였다. 해석결과를 바탕으로 설계시방서에서 제시한 모든 설계요구조건을 만족시킬 수 있도록 수직 Frame의 보강부재를 보강하고, Hoist Rope 용량을 증가시키도록 제안하였다.

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A Study on the Spacing and Required Flexural Rigidity of Cross Beams in Composite Two-Steel Girder Bridges (강합성 2-거더교의 가로보 배치 간격 및 소요 휨강성에 관한 연구)

  • Park, Yong Myung;Cho, Hyun Joon;Hwang, Min Oh
    • Journal of Korean Society of Steel Construction
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    • v.16 no.1 s.68
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    • pp.1-10
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    • 2004
  • A study on the evaluation of proper spacing and required flexural rigidity of cross beams in composite two I-section steel girder bridges without a lateral and sway bracing system was performed. Specifically, a 2-lane, 40-m simple span bridge and a 3-span continuous (40+50+10m) bridge were designed, and structural analyses under dead load before and after composite, live, wind, and seismic loads were performed using spacing and flexural rigidity or cross beams as parameters. Through parametric analysis, the effect on the stresses due to the combination of loads and live load distribution was investigated. In addition. material and geometric nonlinear analyses under dead load before composite were performed to evaluate the lateral buckling strength of the steel girders and cross beam. Based on the results or such analyses, the proper spacing and flexural rigidity of cross beams at intermediate points and supports were proposed.

Estimation of Buckling and Plastic Behaviour according to the Analysis Model of the Stiffened Plate (보강판의 해석모델에 따른 좌굴 및 소성거동 평가)

  • Ko, Jae-Yong;Oh, Young-Cheol;Park, Joo-Shin
    • Journal of Navigation and Port Research
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    • v.31 no.3 s.119
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    • pp.271-279
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    • 2007
  • Ship structures are basically an assembly of plate elements and estimation load-carrying capacity or the ultimate strength is one of the most important criterion for estimated safety assessment and rational design on the ship structure. Also, Structural elements making up ship plated structures do not work separately against external load. One of the critical collapse events of a ship structure is the occurrence of overall buckling and plastic collapse of deck or bottom structure subjected to longitudinal bending. So, the deck and the bottom plates are reinforced by a number af longitudinal stiffeners to increase their strength and load-carrying capacity. For a rational design avoiding such a sudden collapse, it is very important to know the buckling and plastic behaviour or collapse pattern of the stiffened plate under axial compression. In this present study, to investigate effect af modeling range, the finite element method are used and their results are compared varying the analysis ranges. When making the FEA model, six types of structural modeling are adopted varying the cross section of stiffener. In the present paper, a series of FEM elastoplastic large deflection analyses is performed on a stiffened plate with fiat-bar, angle-bar and tee-bar stiffeners. When the applied axial loading, the influences of cross-sectional geometries on collapse behaviour are discussed. The purpose of the present study is examined to numerically calculate the characteristics of buckling and ultimate strength behavior according to the analysis method of ship's stiffened plate subject to axial loading.

Evaluation of Buckling Strength of Non-structured Plates by Using the Deformation Energy (변형에너지에 기반한 비정형 판부재의 좌굴강도 평가기법)

  • Zi, Goangseup;Kim, Hong-hyun;Ahn, Jin-young;Oh, Min-Han
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.21 no.3
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    • pp.102-113
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    • 2017
  • A new index for the buckling strength of non-structured plates is proposed. The external work or the deformation energy caused by the external loads or the boundary displacement controled by a load parameter is calculated along an equilibrium path of the member under consideration. If the second variation of the energy with respect to the parameter loses its positiveness, it defined as the limit of the stability. In contrast to the current method given in codes where the stability limit is evaluated by using only representative internal forces, the evaluation of the stability limit is always consistent even with the change of the distribution of the internal forces on the boundary. If the elasticity is concerned, the result from this proposed approach becomes identical to that from the classical methods.

Fire Damaged Behavior of Real Sized Normal Strength RC Columns (화해를 입은 실물크기 보통강도 RC 기둥의 거동)

  • Lee, Cha-Don;Shin, Yeong-Soo;Hong, Sung-Gul;Lee, Kyung-Ku;Lee, Seung-Whan
    • Journal of the Korea Concrete Institute
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    • v.15 no.6
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    • pp.866-876
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    • 2003
  • Experiments were performed for the real sized 12 reinforced concrete columns of 350${\times}$350${\times}$3350 mm with normal concrete in order to observe the fire-damaged behavior of these columns. Columns were heated according to the ISO heating curve. Main experimental parameters were: magnitude of axial load, heating time, cover thickness, and eccentricity. Effects of these parameters on the axial expansion and contraction, rotation, buckling, ISO fire resistance, and structural stability were experimentally quantified. It has been observed that the contraction rate of axial deformation was affected mostly by the duration of heating time and buckling of reinforcement or member by the magnitude of axial load, duration of heating time, cover thickness and eccentricity in order. Based on the experimental observations, ISO fire resistance criteria were qualiatively criticized.

Evaluation of In-plane Buckling and Ultimate Strength for Braced Arch Ribs (브레이스트 아치 리브의 면내 좌굴 및 극한강도 평가)

  • Park, Yong Myung;Heo, Taek Young;Lee, Pil Goo;Noh, Kyeung Bae
    • Journal of Korean Society of Steel Construction
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    • v.16 no.6 s.73
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    • pp.759-768
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    • 2004
  • The parametric analysis of vertically braced steel pipe arch ribs was performed to evaluate their in-plane buckling strengths and ultimate load-carrying capacities. The elastic and plastic behavior of braced arch ribs, unlike those of the usual single arch ribs, are affected by such factors as the flexural rigidity of the brace member, brace and pipe ribs spacing, loading situation, and arch curvature. To analyze these effects, several parameters were included, such as the rise-to-span ratio, the second moment of the inertia ratio of the rib to the brace member, the space ratio of the brace, the space ratio of the upper and lower ribs, the initial crookedness, the slenderness ratios of the braced arch ribs, and the loading conditions were considered with live-load-to-dead-load ratios. Based on the results of the parametric analyses, a proper profile of the braced arch rib was proposed. A large-scale structural experiment was also performed to evaluate the ultimate strength of the braced arch rib. The test results were determined to reasonably coincide with the analytical ones.

Plastic Analysis of Steel Plate Shear Panels using Strip Model (스트립 모델을 이용한 강판 전단패널의 소성 해석)

  • Lee, Myung Ho;Moon, Tae Sup
    • Journal of Korean Society of Steel Construction
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    • v.18 no.1
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    • pp.71-80
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    • 2006
  • The behaviors of steel-plate shear panels were investigated through an experimental and analytical study, using mild steel (S40). Steel-plate shear panels buckle at small loads, and their strength is based on the shear panel's postbuckling strength due to tension field action. In design practice, however, the capacity of steel-plate shear panels is limited to the elastic buckling strength of shear panels. Th e National Standard on Limit States Design of Steel Structures, CAN/CSA-S16.1-94 (1994) contains a guideline for the analysis of thi n, unstiffened, steel-plate shear walls using the strip model. In this paper, the structural capacity of shear panels was evaluated using the results of the experiment and of the strip model analysis.