• 제목/요약/키워드: horizontal shear

검색결과 657건 처리시간 0.055초

철근콘크리트 깊은 보에서 수평 전단철근의 전단저항에 관한 실험적 연구 (An Experimental Study on the Shear Resistance of Horizontal Shear Reinforcement in R.C. Deep Beams)

  • 양근혁;이영호;은희창;정헌수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.903-906
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    • 2001
  • The objective of this experimental study was to understand the effect of horizontal shear bar on the shear behavior of R.C. deep beams. Therefore, in the test program, the horizontal shear bar ratio($\rho_{sh}$) and shear span-to-overall depth ratio(a/h) are considered as two main variables. Test results indicate that for deep beams with a/h equal to 1.0, horizontal shear bar is less efficient in restricting the diagonal crack width development and enhancing the ultimate shear strength. So, it can be concluded that shear resistance of horizontal shear bar is related to a/h rather than clear span-to-effective depth ratio($l_{n}$/d) recommended in ACI code.

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Third Harmonic Generation of Shear Horizontal Guided Waves Propagation in Plate-like Structures

  • Li, Weibin;Xu, Chunguang;Cho, Younho
    • 비파괴검사학회지
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    • 제36권2호
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    • pp.149-154
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    • 2016
  • The use of nonlinear ultrasonics wave has been accepted as a promising tool for monitoring material states related to microstructural changes, as it has improved sensitivity compared to conventional non-destructive testing approaches. In this paper, third harmonic generation of shear horizontal guided waves propagating in an isotropic plate is investigated using the perturbation method and modal analysis approach. An experimental procedure is proposed to detect the third harmonics of shear horizontal guided waves by electromagnetic transducers. The strongly nonlinear response of shear horizontal guided waves is measured. The accumulative growth of relative acoustic nonlinear response with an increase of propagation distance is detected in this investigation. The experimental results agree with the theoretical prediction, and thus providing another indication of the feasibility of using higher harmonic generation of electromagnetic shear horizontal guided waves for material characterization.

PC 합성보의 수평접합면 전단력 전달성능 평가 및 설계법 분석 (Evaluation of Design Method and Shear Transfer Capacity on the Horizontal Interface of PC Composite Beams)

  • 문정호;오영훈
    • 콘크리트학회논문집
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    • 제25권1호
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    • pp.81-90
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    • 2013
  • 이 연구에서는 합성보의 수평 접합면에 대한 수평전단력 저항성능을 평가하기 위하여 6개의 접합면 전단성능 실험체를 대상으로 접합면의 표면상태, 전단철근의 보강량과 상세 등의 구조변수에 대한 수평전단강도를 평가하였다. 휨압축파괴를 나타낸 SF-291B를 제외한 모든 실험체는 실험계획에서 의도한 대로 접합면의 수평전단력에 의한 전단파괴를 나타내었다. 설계기준식의 수평전단력 전달 또는 전단마찰 설계법으로 산정한 접합면 전단강도는 실험체의 수평전단 파괴를 초래한 접합면의 수평전단내력을 양호한 수준으로 평가하는 것으로 나타났으며, PCI 설계기준에서 제시한 전단철근의 배근상세와 정착길이는 접합면에서 요구되는 수평전단성능을 확보할 수 있다고 판단된다.

Effect of Glass Fiber-Reinforced Connection on the Horizontal Shear Strength of CLT Walls

  • JUNG, Hongju;SONG, Yojin;HONG, Soonil
    • Journal of the Korean Wood Science and Technology
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    • 제48권5호
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    • pp.685-695
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    • 2020
  • The connection performance between cross-laminated timber (CLT) walls and support has the greatest effect on the horizontal shear strength. In this study, the horizontal shear performance of CLT walls with reinforced connection systems was evaluated. The reinforcements of metal bracket connections in the CLT connection system was made by attaching glass fiber-based reinforcement to the connection zone of a CLT core lamina. Three types of glass fiber-based reinforcement were used: glass fiber sheet (GS), glass fiber cloth (GT) and fiber cloth plastic (GTS). The horizontal shear strength of the fabricated wall specimens was compared and evaluated through monotonic and cyclic tests. The test results showed that the resistance performance of the reinforced CLT walls to a horizontal load based on a monotonic test did not improve significantly. The residual and yield strengths under the cyclic loading test were 38 and 18% higher, respectively, while the ductility ratio was 38% higher than that of the unreinforced CLT wall. The glass fiber-based reinforcement of the CLT connection showed the possibility of improving the horizontal shear strength performance under a cyclic load, and presented the research direction for the application of real-scale CLT walls.

철근콘크리트 깊은 보에서 전단철근비와 전단내력의 관계 (The Relationships Between Shear Reinforcement Ratios and Shear Strength in Reinforced Concrete Deep Beams)

  • 양근혁;박정화;정헌수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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    • pp.256-259
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    • 2004
  • The objective of this experimental study is to understand the effects of horizontal and vertical shear reinforcement on the shear strength of concrete deep beams. Main variables were the horizontal shear reinforcement ratio $(P_{sh})$, vertical shear reinforcement ratio$(P_{sv})$ and shear span-to-overall depth ratio(a/h). Test results revealed that the effectiveness of shear resistance of shear reinforcement was greatly related to the a/h. For the beams with $a/h\geq1.0$, the vertical shear reinforcement was more effective than horizontal shear reinforcement.

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Effect of shear wall location in rigid frame on earthquake response of roof structure

  • Ishikawa, Koichiro;Kawasaki, Yoshizo;Tagawa, Kengo
    • Structural Engineering and Mechanics
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    • 제11권6호
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    • pp.605-616
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    • 2001
  • The purpose of this study is to investigate the effect of the shear wall location in rigid frames on the dynamic behavior of a roof structure due to vertical and horizontal earthquake motions. The study deals with a gabled long span beam supported by two story rigid frames with shear walls. The earthquake response analysis is carried out to study the responses of the roof: vibration mode, natural period, bending moment and horizontal shear force of the bearings. The study results in the following conclusions: First, a large horizontal stiffness difference between the side frames is caused by the shear wall location, which results in a large vertical vibration of the roof and a large shear force at the side bearings. Second, in this case, the seismic design method for ordinary buildings is not useful in determining the distribution of the static equivalent loads for the seismic design of this kind of long span structures.

대형판조립식 구조 수직.수평접합부의 전단강도에 미치는 보강방법의 영향-수직접합부 및 슬래브-슬래브 수평접합부를 중심으로- (Effects of Reinforcing Method Influnced to the Shear Strength of Vertical and Horizontal Joints in Precast Concrete Large Panel Structures -Focused on the Vertical Joints and Slab-Slab Type Horizontal Joints-)

  • 정란;박현수;조승호
    • 콘크리트학회지
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    • 제8권4호
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    • pp.171-179
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    • 1996
  • PC판넬 조립식 구조의 수직.수평접합부의 유용한 접합형태에 따라 접합부 전단내력을 상승시킬 수 있는 접합부 설계의 기본 형태를 제시하는데 연구의 목적이 있다. 시험체는 수직접합부의 경우 전단키의 개수 및 보강철물의 종류에 변수를 주고 수평접합부의 경우에는 전단키의 갯수 및 가력방향에 변수를 주어 총 22개의 시험체를 제작하여 실험하였다. 결론적으로 수직접합부의 경우, 수평보강철물이 있는 시험체는 기존의 다른 실험결과와 마찬가지로 수평보강철물이 없는 시험체에 비하여 연성이 크게 나타났다. EH한 와이어로프와 원형철근 두 종류의 보강철물을 사용하여 실험한 결과 와이어 로프를 사용한 시험체는 원형철근을 사용한 시험체와 최대내력 및 전단강성 등 전체적인 구조거동이 거의 비슷하게 나타났다.

접착식 콘크리트 덧씌우기 포장의 부착거동 연구 (A Study on the Bond-Behavior of Bonded Concrete Overlays)

  • 김영규;이승우;한승환
    • 한국도로학회논문집
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    • 제14권5호
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    • pp.31-45
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    • 2012
  • PURPOSES: In Korea, rapid maintenance of distressed concrete pavement is required to prevent traffic jam of the highway. Asphalt concrete overlay has been used as a general maintenance method of construction for aged concrete pavement. AC overlay on existing concrete pavements experience various early distresses such as reflection crack, pothole and rutting, due to different physical characteristics between asphalt overlay and existing concrete pavement. Bonded concrete overlay(BCO) is a good alternative since it has advantages that can reduce various distresses during the service life since overlay material has similar properties with existing concrete pavements. Recently, BCO which uses the ultra rapid harding cement has been applied for maintenance of highway. BCO has advantage of structural performance since it does monolithic behave with existing pavement. Therefore, it is important to have a suitable bond strength criteria for securing performance of BCO. Bond strength criteria should be larger than normal tensile stress and horizontal shear stress occurred by traffic and environmental loading at bond interface. Normal tensile stress and horizontal shear stress need to estimated for the establishment of practical bond strength criteria. METHODS: This study aimed to estimate the bond stresses at the interface of BCO using the three dimensional finite element analysis. RESULTS: As a result of this study, major failure mode and maximum bond stress are evaluated through the analysis of normal tensile stress and horizontal shear stress for various traffic and environmental load conditions. CONCLUSIONS: It was known that normal tensile stresses are dominated by environmental loading, and, horizontal shear stresses are dominated by traffic loading. In addition, bond failure occurred by both of normal tensile stresses and horizontal shear stresses; however, normal tensile stresses are predominated over horizontal shear stresses.

대형판 프리캐스트 콘크리트 구조 수평접합부의 전단내력에 대한 실험적 연구 (An Experimental Study on the Shear Resistance of Horizontal Joints in Precast Concrete Large Panel Structures)

  • 정창용;현원창;엄철환;어양석;김상식
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1992년도 가을 학술발표회 논문집
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    • pp.208-213
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    • 1992
  • This research is related to the experimental verification of the shear resistance of horizontal joint in precast concrete large panel structures. a total of 9 spicemens was tested to assess their shear resistance. In the tests lateral forces have been applied to the specimen to cause shear failure while keeping the axial compression consistantly. The shear resistances of the specimens have been evaluated by investigating the deformations and failure modes of the specimens. From the test results, it is observed that the shear resistance of the horizontal joints of P.C panel structures are closely connected with shear friction mechanism.

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철근콘크리트 깊은보에서 전단보강근량 및 배치가 전단거동에 미치는 효과 (The Shear Effects of the Web Reinforcement Area and Arrangement in R.C. Deep Beams)

  • 윤정민;김미경;연규원;박찬수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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    • pp.885-890
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    • 2000
  • 12 RC deep beams with a/d = 1.17 are reported. This paper is to study the effect of vertical and horizontal web reinforcement and web reinforcement arrangement on inclined cracking shear, ultimate shear strength, midspan deflection, and inclined crack width. Test results indicated that web reinforcement produces and arrangement seems to moderately affect inclined cracking shear, ultimate shear strength and crack width. However, addition of horizontal web reinforcement(pv = 0.0085) little or no influence on inclined cracking shear, ultimate shear strength and crack width. The member which vertical and horizontal web reinforcement concentrate on the center web considerably increases in load-carrying capacity.