• 제목/요약/키워드: cyclic shear test

검색결과 428건 처리시간 0.03초

Shear mechanism and bearing capacity calculation on steel reinforced concrete special-shaped columns

  • Xue, J.Y.;Chen, Z.P.;Zhao, H.T.;Gao, L.;Liu, Z.Q.
    • Steel and Composite Structures
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    • 제13권5호
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    • pp.473-487
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    • 2012
  • An experimental study was performed to investigate the seismic performance of steel reinforced concrete (SRC) special-shaped columns. For this purpose, 17 steel reinforced concrete special-shaped column specimens under low-cyclic reversed load were tested, load process and failure patterns of the specimens with different steel reinforcement were observed. The test results showed that the failure patterns of these columns include shear-diagonal compression failure, shear-bond failure, shear-flexure failure and flexural failure. The failure mechanisms and characteristics of SRC special-shaped columns were also analyzed. For different SRC special-shaped columns, based on the failure characteristics and mechanism observed from the test, formulas for calculating ultimate shear capacity in shear-diagonal compression failure and shear-bond failure under horizontal axis and oblique load were derived. The calculated results were compared with the test results. Both the theoretical analysis and the experimental results showed that, the shear capacity of T, L shaped columns under oblique load are larger than that under horizontal axis load, whereas the shear capacity of +-shaped columns under oblique load are less than that under horizontal axis load.

Shear behavior of short square tubed steel reinforced concrete columns with high-strength concrete

  • Li, Xiang;Zhou, Xuhong;Liu, Jiepeng;Wang, Xuanding
    • Steel and Composite Structures
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    • 제32권3호
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    • pp.411-422
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    • 2019
  • Six shear-critical square tubed steel reinforced concrete (TSRC) columns using the high-strength concrete ($f_{cu,150}=86.6MPa$) were tested under constant axial and lateral cyclic loads. The height-to-depth ratio of the short column specimens was specified as 2.6, and the axial load ratio and the number of shear studs on the steel shape were considered as two main parameters. The shear failure mode of short square TSRC columns was observed from the test. The steel tube with diagonal stiffener plates provided effective confinement to the concrete core, while welding shear studs on the steel section appeared not significantly enhancing the seismic behavior of short square TRSC columns. Specimens with higher axial load ratio showed higher lateral stiffness and shear strength but worse ductility. A modified ACI design method is proposed to calculate the nominal shear strength, which agrees well with the test database containing ten short square TSRC columns with shear failure mode from this study and other related literature.

균열 및 비균열 철근콘크리트 기둥의 탄소섬유시트 전단보강효과에 관한 실험적 연구 (Experimental Study on the Shear Strengthening Effect of Cracked or Uncracked RC Columns with Carbon Fiber Sheets)

  • 나정민;이용택;김승훈;이리형
    • 한국구조물진단유지관리공학회 논문집
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    • 제6권4호
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    • pp.243-254
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    • 2002
  • This study investigates the structural behavior of cracked or uncracked RC columns retrofitted with CFS and evaluates the shear retrofit performance through experiment. Experimental works were conducted for sixth specimens varied in the adhesion method of CFS, the ratio of shear reinforcement bar, and the existence of crack before retrofitting. Throughout cyclic test, the strength, stiffness, failure modes, and ductility are discussed. The test results show that the retrofitting method with CFS improve the shear strength and ductility. The crack width below 2mm, occurred before retrofitting, didn't reduce the shear strengthening effect.

Experimental study on the fatigue performance of aluminum foam sandwich with 304 stainless steel face-sheet

  • Yan, Chang;Jing, Chuanhe;Song, Xuding
    • Steel and Composite Structures
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    • 제39권3호
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    • pp.229-241
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    • 2021
  • This work focused on aluminum foam sandwich (AFS) with different foam core densities and different face-sheet thicknesses subjected to constant amplitude three-point bending cyclic loading to study its fatigue performance. The experiments were conducted out by a high frequency fatigue test machine named GPS-100. The experimental results showed that the fatigue life of AFS decreased with the increasing loading level and the structure was sensitive to cyclic loading, especially when the loading level was under 20%. S-N curves of nine groups of AFS specimens were obtained and the fatigue life of AFS followed three-parameter lognormal distribution well. AFS under low cyclic loading showed pronounced cyclic hardening and the static strength after fatigue test increased. For the same loading level, effects of foam core density and face-sheet thickness on the fatigue life of AFS structure were trade-off and for the same loading value, the fatigue life of AFS increased with aluminum foam core density or face-sheet thickness monotonously. Core shear was the main failure mode in the present study.

反復三軸壓縮試驗에 의한 砂質土의 液狀化 評價에 관한 硏究 (A Study on the Evaluation of Liquefaction of Sandy Soils by the Cyclic Triaxial Compression Test)

  • 고재만;도덕현
    • 한국농공학회지
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    • 제33권3호
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    • pp.51-62
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    • 1991
  • A comprehensive laboratory investigation of the liquefaction characteristics of Jumunjin standard sand. Seoul sand and Hongsung sand was peformed by the undrained cyclic triaxial compression test under different relative densities, confining pressures and cyclic deviator stresses. The results obtained are as follows ; 1. Liquefaction potential was dominated by the stress ratio at a given number of cycle. That is, the number of cycle required to cause initial liquefaction became samller as the stress ratio increased. 2. Liquefaction potential of a sand was infliuenced by initial relative density or void ratio. Under a given relative density. liquefaction potential of Jumunjin standard sand and Seoul sand was smaller than that of Hongsung sand. 3. The pore pressure ratio of Hongsung sand was the smallest three under a given relative density and stress ratio, and it showed higher value when the cyclic stress and the shear strain were high. 4. An excessive pore pressure ratio not found when initial shear was smaller than 0.01%, and the pore pressure ratio started to increase when initial shear became greater than 0.01%. 5. Soil texture is an important factor to cause liquefaction, and liquefaction potential decreased a the mean grain size decreased. however the sand having fine grain such as Hongsung sand showed somewhat higher liquefaction potential. 6. Based on the analysis of the specimens whose number of the cycles to cause liquefaction was 8~12, it was found that the relationship between density and stress ratio was linear. The curves for Hongsung sand was steeper than the other. 7. From the above results and the method suggested by Seed-Idriss, it may be considered that the damages by Hongsung earthquake was not directly caused by liquefaction.

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Lessons from the analysis of a 3-D concrete shear wall

  • Vecchio, F.J.
    • Structural Engineering and Mechanics
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    • 제6권4호
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    • pp.439-455
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    • 1998
  • A three-dimensional static nonlinear finite element analysis was performed on the NUPEC large-scale flanged shear wall, which was the subject of an international study program. Details of the constitutive models and analysis procedures used are provided, and the results of the analysis are presented and discussed. The analytical results are compared to the experimentally observed behaviour, and reasonable correlation is observed. Deficiencies in the modelling are identified. In addition, a parametric study is undertaken to investigate factors and mechanisms influencing both the observed behaviour and the calculated response. Finally, a cyclic load analysis of the wall is described and discussed. The paper serves to point out aspects in modelling that are critical to both producing realistic results, and correctly interpreting those results.

Constitutive models of concrete structures subjected to seismic shear

  • Laskar, Arghadeep;Lu, Liang;Qin, Feng;Mo, Y.L.;Hsu, Thomas T.C.;Lu, Xilin;Fan, Feng
    • Earthquakes and Structures
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    • 제7권5호
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    • pp.627-645
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    • 2014
  • Using OpenSees as a framework, constitutive models of reinforced, prestressed and prestressed steel fiber concrete found by the panel tests have been implemented into a finite element program called Simulation of Concrete Structures (SCS) to predict the seismic behavior of shear-critical reinforced and prestressed concrete structures. The developed finite element program was validated by tests on prestressed steel fiber concrete beams under monotonic loading, post tensioned precast concrete column under reversed cyclic loading, framed shear walls under reversed cyclic loading or shaking table excitations, and a seven-story wall building under shake table excitations. The comparison of analytical results with test outcomes indicates good agreement.

반복하중을 받는 철근콘크리트 저형 전단벽의 이력거동에 관한 실험적 연구(II) -바벨형 단면(Barbell Shape)의 내력과 연성을 중심으로- (Experimental Study on the Hysteretic Behavior of R/C Low-Rise Shear Walls under Cyclic Loads)

  • 최창식;이용재;윤현도;이리형
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1991년도 가을 학술발표회 논문집
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    • pp.68-73
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    • 1991
  • Results of an experimental investigation of low-rise reinforced concrete shear walls with barbell cross section under cyclic loads are discussed and evaluated. Four halr scale models of test specimens with height to length ratio of 0.75 were experimented. The dimension of all walls is 1500mm wide $\times$ 950 mm high $\times$ 100 mm thick and the section of all boundary column at both ends is 200 mm $\times$ 200mm. Main variables are : design concept, vertical flexural reinflrcement ratios and reinforcement details(including crossed diagonal shear reinforcement in SW7 specimen). In SW7 specimen, maximum strength and consequently dissipating energy index were 1.45 and 1.28 times greater than those of SW6 specimen, respectively.

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압축과 전단 하중을 받는 인공 암석 절리의 수리적 거동에 관한 실험적 연구 (An Experimental Study for the Hydraulic Behavior of Artificial Rock Joint under Compression and Shear Loading)

  • 이희석;박연주;유광호;이희근
    • 터널과지하공간
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    • 제10권1호
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    • pp.45-58
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    • 2000
  • 다양한 하중 조건하의 암석 절리에 대한 수리적 거동을 규명하기 위해서 수리전단 시험이 가능한 주기 전단시험 시스템을 설계, 제작하였다. 실험실에서 인공 절리 시료에 대한 압축,전단 조건하의 수리 시험을 실시하였다. 시험 전의 시료에 대한 3차원 간극 측정을 통해 절리의 간극 분포 특성을 규명하였다. 수직응력에 따른 투수계수 변화는 기존 수리 모델과 잘 일치하였다. 전단 하중하의 수리적 거동은 초기에는 팽창 특성을 따랐으며, 팽창의 증가에 따라 투수계수가 커겼다. 전단이 진행됨에 따라 유동률은 충전물 생성과 간극의 엇갈림으로 인해 다소 일정해졌다. 주기전단 하의 수리 거동 역시 돌출부 손상과 충전물 생성의 영향을 받았다. 또한 압축과 전단 하중하의 수리 간극과 역학 간극의 관계가 조사, 비교되었다.

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전단벽의 덮개재료에 따른 전단저항 성능 (Shear Load Performance Test in Accordance with Sheathing Materials of Shear Wall)

  • 장상식;신일중;김윤희
    • 농업과학연구
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    • 제37권2호
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    • pp.271-276
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    • 2010
  • In this study, the light-frame wood shear walls according to the sheathing materials was carried out to investigate the shear load performance. Most common sheathing materials are the structural OSB and gypsum board used to consist wall of wood-frame house. Seven different type of specimens are composed of several sheathing materials and shear test was taken to evaluate shear performance by KS F 2154. As a result, shear walls(G12.5/G12.5 and G12.5/OSB) show that maximum shear strength and shear rigidity modulus are 7316N/mm${\cdot}$118.25 N/mm and 11129 N/mm${\cdot}$184.66 N/mm respectively. The shear wall using gypsum board 15mm improve maximum shear strength and shear rigidity modulus about 30%. The shear wall using 15mm gypsum board showed intermediate value in one side specimens. Different types of shear walls could be compared with the shear load performance. Also, nailed joint failure aspects are different to sheathing material and installing method.