• Title/Summary/Keyword: 좌굴파괴

Search Result 113, Processing Time 0.021 seconds

Compression Tests for Stiffened Steel Plate-Concrete Structures with Variation of B/t Ratio (스터드 간격과 강판두께의 비를 변수로 한 보강 강판-콘크리트 구조의 압축실험)

  • Choi, Byong Jeong;Han, Hong Soo;Kim, Won Ki;Lee, Seung Joon;Kim, Woo Bum
    • Journal of Korean Society of Steel Construction
    • /
    • v.20 no.4
    • /
    • pp.549-559
    • /
    • 2008
  • The objective of this paper is to identify the compression forces and inelastic failure mode using stiffened steel plate-concrete structures. The compression tests were carried out for the three types of B/t ratios by 25, 33 and 50. The test results proved that the compressive strength of the stiffened SC structures can be estimated by the summation of the strengths both stiffened steel plate and concrete. The buckling of the steel plates had been occurred at the plates between studs. The empirical estimation of compressive strength for the stiffened SC structures under compressive loadings was suggested. The buckling behavior also compared with the results of the finite element analysis. The good agreement has been achieved between the experimental results and finite element results.

Study of Failure Mode and Static Behavior of Lightweight FRP Truss Bridge Deck System (복합재료 트러스 교량시스템의 정적거동 및 파괴모드에 관한 해석적 연구)

  • Jung, Woo-Young;Lee, Hyung-Kil
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.20 no.5
    • /
    • pp.511-520
    • /
    • 2007
  • There is a concern with worldwide deterioration of highway bridges, particularly reinforced concrete. The advantages of fibre reinforced plastic(FRP) composites over conventional materials motivate their use in highway bridges for replacement of structures. Recently, an FRP deck has been installed on a state highway, located in New York State, as an experimental project. In this paper, a systematic approach for analysis of this FRP deck bridge is presented. Multi-step linear numerical analyses have been performed using the finite element method to study the structural behavior and the possible failure mechanism of the FRP deck-superstructure system. Deck's self-weight and ply orientations at the interface between steel girders and FRP deck are considered in this study. From this research, the results of the numerical analyses were corroborated with field test results. Analytical results reveal several potential failure mechanism for the FRP deck and truss bridge system. The results presented in this study may be used to propose engineering design guideline for new and replacement FRP bridge deck structure.

Seismic Design of Long Span Structures Based on Hysteric Energy Absorption Mechanism(1) (이력에너지흡수 원리를 이용한 대경간 구조물의 내진설계(1) -이선형 탄소성 이력거동에 의안 에너지 소산원리를 이용하는 방법-)

  • Cheong, Myung-Chae;Won, Sung-Dae
    • Journal of Korean Association for Spatial Structures
    • /
    • v.10 no.1
    • /
    • pp.85-93
    • /
    • 2010
  • This paper suggests a vibration control method long span structures with trussed roof. Basic concept of this method is based on the energy absorption through hysteresis loop of an elasto-plastic element. This element is attached on the top of the column supporting the roof. Two different types of roofs and three of earthquake waves are used in the investigation. It shows that this is very efficient method to reduce the seismic energy of roof member transferred from the column.

  • PDF

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
    • /
    • v.6 no.4 s.22
    • /
    • pp.35-44
    • /
    • 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.

  • PDF

Experimental Investigation of The Lateral Retrofitting Effect of FRP Sheet and Buckling-restrained Braces for Beam-Column Joints (FRP Sheet와 비좌굴 가새를 적용한 보-기둥 접합부의 횡방향 보강효과에 관한 실험적 연구)

  • Byon, Eun-Hyuk;Kim, Min-Sook;Lee, Young-Hak;Kim, Hee-Cheul
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.15 no.1
    • /
    • pp.49-56
    • /
    • 2011
  • The strengthening effect of CFRP sheet and AFRP sheet with buckling-restrained brace for Beam-Column joints under constant axial and cyclic lateral loading is evaluated experimentally in this paper. Six test specimens were constructed. The main test parameters included the FRP Sheet and Buckling-restrained braces. The results of the tests were analyzed by focusing on their mode of failure, maximum load, ductility indexes, and energy dissipation capacity. Test results indicated that CFRP Sheet with the buckling-restrained brace system significantly increased the strength and stiffness of the specimen and that it was the most adequate retrofitting method.

Deformation and Fracture Analysis of Honeycomb Sandwich Composites under Bending Loading (굽힘 하중을 받는 하니컴 샌드위치 복합재료의 변형 및 파괴 해석)

  • Kim Hyoung-Gu;Choi Nak-Sam
    • Composites Research
    • /
    • v.18 no.1
    • /
    • pp.30-37
    • /
    • 2005
  • The bending strength characteristics and local deformation behaviors of honeycomb sandwich composites were investigated using three-point bending experiment and finite element simulation with a real model of honeycomb core. Two kinds of cell sizes of honeycomb core, two kinds of skin layer thicknesses, perfect bonding specimen as well as initial delamination specimen were used for analysis of stress and deformation behaviors of honeycomb sandwich beams. Various failure modes such as skin layer yielding, interfacial delamination, core shear deformation and local buckling were considered. Its simulation results were very comparable to the experimental ones. Consequently, cell size of honeycomb core and skin layer thickness had dominant effects on the bending strength and deformation behaviors of honeycomb sandwich composites. Specimens of large core cell size and thin skin layer showed that bending strength decreased by $30\~68\%$.

Impact Buckling Reliability Analysis of Stiffened Cylinder With Initial Geometric Imperfection (기하학적 초기형상결함을 갖는 보강 원통의 충격좌굴 신뢰성 해석)

  • 김두기
    • Journal of KSNVE
    • /
    • v.6 no.6
    • /
    • pp.735-747
    • /
    • 1996
  • In this paper, buckling reliability analyses of stiffened cylinder with random initial geometric imperfection under axial impact load are performed by the combined response surface method. The effect of random geometric imperfection on the failure probability and reliability is recognized quantitatively. Buckling reliability decreases with the increase of mean value, cov of initial geometric imperfection under the same external load. Buckling probability under impact load is greater than those under static load with the same condition. From the probabilistic characteristics of imapct buckling load, relation between reliability index and safety parameter can be obtained in addition to the relation between load and reliability index. And those results can be used to determine the range of required safety parameter and acceptable imperfaction.

  • PDF

Influence of Geometric Initial Imperfection on the First Buckling Time Variation of Cylinder Under Impact Load (충격하중을 받는 원통의 최초좌굴시간의 변동성에 대한 기하학적 초기결함의 영향)

  • 김두기
    • Computational Structural Engineering
    • /
    • v.10 no.1
    • /
    • pp.173-183
    • /
    • 1997
  • In this paper a method is suggested for the probabilistic analysis of impact buckling failure time of cylinder with random axisymmetric geometric imperfection under axial impact. Failure is assumed as axisymmetric radial deformation exceeds the given criteria for the first time. For the generation of random geometric initial imperfection, random field theory by mean function and autocorrelation function of geometric imperfection is used. Suggested method is useful for the treatment of the randomness of realistic geometric imperfection and can be used for the structural safety analysis of cylinder considering its effect.

  • PDF

Experimental Study on Buckling Restrained Knee Bracing Systems Using Bolted Channel Sections (볼팅 고정 채널 형강 보강재를 이용한 비좌굴 Knee Bracing System의 내진성능에 대한 실험 연구)

  • Lee, Jin;Lee, Ki-Hak;Lee, Sung-Min;Shin, Ji-Wook;Kim, Young-Min
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.13 no.2
    • /
    • pp.37-46
    • /
    • 2009
  • In this study, the seismic performance of the Buckling Restrained Knee Bracing (BRKB) system was evaluated through a pin-connected 1-bay 1-story frame. The BRKB system using a bolted channel section developed was composed of a steel plate as a load-resisting core member and two channel sections as a restrainment of the local and global buckling of the core plate. The main purpose of the BRKB system is to be used as an effective tool to re-strengthen/rehabilitate old low- and mid-rise RC frame buildings, which do not have enough seismic resistance to earthquake loadings. The main variables for the test specimens were the size of the core plates, stiffeners and the use of guide plates. The test results showed that the size of the core plate, which was the main element for the load-resisting member, was the most important parameter to achieve ductile behavior under tension as well as compression, until the maximum displacement exceed twice the design drift limit given by the AISC Seismic Provisions.

Compression Tests for Unstiffened Steel Plate-Concrete Structures with Variation of B/t Ratio (스터드 간격과 강판두께의 비를 변수로 한 비보강 강판-콘크리트 구조의 압축실험)

  • Choi, Byong Jeong;Han, Hong Soo;Kim, Won Ki;Lee, Seung Joon;Kim, Woo Bum
    • Journal of Korean Society of Steel Construction
    • /
    • v.20 no.4
    • /
    • pp.561-570
    • /
    • 2008
  • The primary object of the paper is to identify the compression forces and inelastic failure behavior using steel plate-concrete structures. The compression tests were carried out for the three types of B/tratios by 25, 33 and 50. The tests proved that the compressive strength of the SC structures can be estimated by the summation of strengths both of the steel plate and concrete. The buckling of the steel plates had been occurring at the plates between studs. The empirical estimation of compressive strength for unstiffened SC structures under compressive loadings was suggested. The buckling behavior was also compared with the results of the finite element analysis.