• 제목/요약/키워드: Effective Width

검색결과 1,186건 처리시간 0.03초

기존 실험데이터를 통한 철근콘크리트 이형벽체의 휨내력식 평가 (Evaluation of Flexural Capacity of Reinforced Concrete Irregular Walls Based on Existing Experimental Data)

  • 문경신;하상수;최창식;이원호;이리형
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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    • pp.845-850
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    • 2001
  • The primary objective of this study is to develop the new equation that can predict the flexural strength of irregular walls by applying the concept of the effective width which is used in current codes. Results obtained from this data analysis are as follows : 1. It is conservative to use PCI provision and ACI code as the effective width for evaluating the flexural capacity of irregular walls 2. The result of this study shows that the Paulay & Priestley's proposition is available for more exactly and safely predicting flexural capacity of irregular walls throughout a reduction factor.

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On the post-buckling behaviour of plates under stress gradient

  • Bedair, Osama K.
    • Structural Engineering and Mechanics
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    • 제4권4호
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    • pp.397-413
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    • 1996
  • In this paper the elastic post-buckling behaviour of plates under non-uniform compressive edge stress is investigated. The compatibility differential equations is first solved analytically and then an approximate solution of the equilibrium equation is obtained using the Galerkin method. Explicit expressions are derived for the load-deflection, ultimate strength and membrane stress distributions. Analytical effective width formulations, based on the characteristics of the stress field of the buckled plate, are proposed for this general loading condition. The predicted load-deflection expression is compared with independent test results. Results are also presented detailing the load-deflection behaviour and stress distribution for various aspect ratios.

기둥단면형상에 따른 무량구조시스템 강성변화에 관한 연구 (A study on stiffness of flat-plate system according to column section shape)

  • 강수민;이지웅;김욱종;이도범
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.314-317
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    • 2006
  • In the present study, design methodologies for effective width of slabs in slab-column connections were evaluated in comparison with the experimental results on the full-scale slab-column connections. The design methodologies are as follows: the methodology proposed by Jacob S. Grossman and the methodology proposed by Choi & Song. The former does not predict the stiffness change of the slab-column connection due to the change in the column section shape and the latter overestimates the stiffness when edge length of the column section in the loading direction is long. Accordingly, the equation to calculate the effective width of slabs should be modified to reflect the effect of the change in the column section shape.

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Gabor 코사인과 사인 변환 (A Gabor Cosine and Sine Transform)

  • 이적식
    • 대한전자공학회논문지SP
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    • 제39권4호
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    • pp.408-417
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    • 2002
  • Gabor 코사인과 사인 함수는 인간시각 필터를 설명하기 위해서 많이 사용된다. 이 함수들로 영상주파수 성분을 국부적으로 표현하는 새로운 방법을 본 논문에서 제안한다. 직류 맥류와 계단입력에 대한 사이드 로브의 강도에 기초하여 기저함수의 변수들을 선택한다. Gabor 코사인과 사인으로 구성되는 결과적인 변환에 대해서 결합유효폭을 계산하고, 한정된 변환 계수만으로 영상을 복원하여 기존의 방법과 비교 검토한다. 제안한 변환이 DGT와 DCT보다 더 좋은 성능 결과를 나타낸다.

개폐식 밸브를 사용한 공기압 서보 시스템의 효율적 밸브 개폐 방법에 관한 연구 (Study on the Effective Operating Method of on-off Valves for a Pneumatic Servo System)

  • 황웅태;최서호;이정오
    • 한국정밀공학회지
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    • 제15권1호
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    • pp.109-116
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    • 1998
  • This paper is concerned with effective operating method of pneumatic on-off valves for improving position control accuracy, valve life-time and position settling time using modified pulse width modulation with dead-zone (MPWMD). The pneumatic system using on-off valves has advantage of simple construction and low cost compared with a system with servo-valves. The performance of the proposed control method is investigated experimentally for the position control of a pneumatic cylinder using on-off valves. Experimental results show that the proposed algorithm for valve operation can be used to obtain fast and accurate position control compared to the conventional PWMD algorithm. It is also shown that the use of the proposed MPWMD algorithm for the position control significantly reduces the number of valve switching and noise.

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잔디생육에 대한 유기물, 활성탄소 및 마그네슘의 효과 (Effect of Organic Material, Active Carbon and Magnesium on the Growth of Zoysia koreana)

  • 최병주;심재성;밝훈
    • 아시안잔디학회지
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    • 제8권3호
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    • pp.193-199
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    • 1994
  • Effect pf rape seed oil cake compast (OM) active carbon(C) compound fertilizer (NPK) and magnesium sulfate (Mg) application on Zoysia koreana growth by lysimeter of 50cm soil column filled with a low fertility loam. Effect on growth was in order of OM>OM . NPK interaction> NPK . active carbon and Mg were not effective OM . NPK interaction effect was negative on leaf width and root dry matter yield. OM and OM . NPK interaction were most effective on rhizome growth. Their effect did not change the ratio of growth rates between aerial part and rhizome but change that between aerial part and root. Leaf width was most sensitive to the treatments.

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기둥 지지된 슬래브교의 모멘트 간략산정법에 관한 연구 (Bending Moment Analysis simpiified in Slab Bridges supported by Column Type Piers)

  • 이채규;김영인;김우
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1992년도 가을 학술발표회 논문집
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    • pp.73-78
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    • 1992
  • It would be much effective that single column type pier is used in concrete slab bridges rather than gravity type pier is used. To determine the longitudinal bonging moment in concrete slab bridges supported by single column type piers, the concept of effective width is applied. By elastic plate theory cooperated with finite element method, the distribution of the longitudinal moment of the slab supported by single column type piers is studied. The main variables are span, width, and thickness of the slab and column section size. Then the analytical results obtained are summarized and analysed to evaluate the maximum longitudinal negative moment by simple beam analysis.

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플랫 플레이트 슬래브 해석을 위한 강성감소계수 제안 (Stiffness Reduction Factor for Flat Plate Slabs)

  • 박영미;한상환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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    • pp.337-340
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    • 2006
  • The purpose of this study is to propose the stiffness reduction factor for flat plate slabs under lateral loads. Current design code (e.g., ACI 318-05) requires considering the effects of cracks for calculating slab stiffness under lateral loads. This study collected the test results of 20 interior slab-column connections, from which stiffness reduction in each test was estimated with respect to the ratio of applied moment to cracking moment ($M_a/M_{cr}$). Based on collected data, this study proposed equations for calculating stiffness reduction with respect to $M_a/M_{cr}$. To verify the proposed equations, this study conducted the experimental test of interior slab-column connections under quasi-static cyclic loading. From the test, load-deformation curve is compared to that obtained from effective beam width method with the proposed equation for the stiffness reduction. It is shown that the effective beam width method with the proposed equation for stiffness reduction predicts accurately the test results.

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Compressive performance with variation of yield strength and width-thickness ratio for steel plate-concrete wall structures

  • Choi, Byong-Jeong;Kim, Won-Ki;Kim, Woo-Bum;Kang, Cheol-Kyu
    • Steel and Composite Structures
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    • 제14권5호
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    • pp.473-491
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    • 2013
  • The primary objectives of this paper are to describe the buckling patterns and to determine the squash load of steel plate-concrete (SC) walls. The major variables in this study were the width-thickness (B/t) ratio and yield strength of surface steel plates. Six SC walls were tested, and the results include the maximum strength, buckling pattern of steel plates, strength of headed studs, and behavior of headed studs. Based on the test results, the effects of the B/t ratio on the compressive strength are also discussed. The paper also presents recommended effective length coefficients and discusses the effects of varying the yield strength of the steel plate, and the effects of headed studs on the performance of SC structures based on the test results and analysis.

보존충전제(保存充塡劑)의 항균작용(抗菌作用)에 관(關)한 실험적(實驗的) 연구(硏究) (EXPERIMENTAL STUDY ON THE ANTIBACTERIAL EFFICACY OF A FEW FILLING MATERIALS)

  • 김영해
    • Restorative Dentistry and Endodontics
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    • 제5권1호
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    • pp.25-28
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    • 1979
  • The antibacterial efficacy of a few filling materials were studied in vitro. Zinc oxide eugenol cement. dycal, cavitec, hipol, cervident, clearfill and microfill were tested against Staphylococcus albus and Lactobacillus acidophilus on thioglycolate agar in order to determine whether the materials are effective inhibitors of bacterial growth. 1. Of these materials tested, zinc oxide eugenol cement was the most effective inhibitor of bacterial growth and revealed about 5.5mm in width of inhibition zone against Staphylococus albus and about 5.0mm against Lactobcillus acidophilus. 2. Dycal was moderate inhibitor of the both bact$\={e}$ria showing 2.5mm of the zone in width. 3. Cavitec was the slightest effect against the both bacteria 4. Composite resins tested in this study showed no evidence of inhibiting bacterial growth against the both bacteria.

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