• 제목/요약/키워드: eurocode

검색결과 357건 처리시간 0.025초

이종강도 부재간 연결면 조건에 따른 전단강도 평가 (Evaluation of Shear Strength of Concrete Layers with Different Strength considering Interfacial Indentation)

  • 강재윤;박종섭;정우태;금문성
    • 한국산학기술학회논문지
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    • 제17권8호
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    • pp.449-455
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    • 2016
  • 본 연구에서는 Eurocode에서 제시하는 콘크리트 부재간 계면조건을 고려한 전단강도 설계식을 압축강도가 서로 다른 부재 연결부에 대해서도 적용할 수 있는지를 검토하기 위하여 전단실험을 수행하고 설계 평가식과 비교하였다. Eurocode에서 제시하는 전단강도 평가식의 변수를 고려하여 콘크리트 압축강도, 전단철근 보강비, 요철계면을 변수로 하는 부재를 제작하였고, 콘크리트층 간의 강도 차이와 요철계면의 유무에 따른 전단강도에 주안점을 두고 전단실험을 수행하였다. 실험을 통해 계측한 실제 전단강도를 Eurocode의 전단강도 평가식을 이용한 계산값과 비교하여 실제 전단강도 수준과 평가식과의 차이를 평가하였으며, 이종강도를 갖는 콘크리트 층에서 압축강도가 증가함에 따라 전단강도도 증가하며, 계면요철을 둔 연결부 전단강도는 설계기준의 평가식으로 계산한 값에 비해 20~50%까지 차이를 보이는 것으로 나타났다. 철근보강비가 작은 경우에는 계면요철에 의한 전단저항력이 전단강도에 주로 기여하며, 이 경우에는 계면에서의 급격한 파괴가 일어나는 현상과 전단강도 편차가 크게 나타남에 따라 평가식과 큰 차이를 보였다. 특히, 이종강도를 갖는 콘크리트 층의 전단강도는 압축강도 차이가 클수록 강도 평가식과 큰 차이를 보이는 것으로 판단된다.

Seismic repair of reinforced concrete beam-column subassemblages of modern structures by epoxy injection technique

  • Tsonos, Alexander G.
    • Structural Engineering and Mechanics
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    • 제14권5호
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    • pp.543-563
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    • 2002
  • The use of the epoxy pressure injection technique to rehabilitate reinforced concrete beam-column joints damaged by strong earthquakes is investigated experimentally and analytically. Two one-half-scale exterior beam-column joint specimens were exposed to reverse cyclic loading similar to that generated from strong earthquake ground motion, resulting in damage. Both specimens were typical of new structures and incorporated full seismic details in current building codes. Thus the first specimen was designed according to Eurocode 2 and Eurocode 8 and the second specimen was designed according to ACI-318 (1995) and ACI-ASCE Committee 352 (1985). The specimens were then repaired with an epoxy pressure injection technique. The repaired specimens were subjected to the same displacement history as that imposed on the original specimens. The results indicate that the epoxy pressure injection technique was effective in restoring the strength, stiffness and energy dissipation capacity of specimens representing a modem design.

The EC3 approach to the design of columns, beams and beam-columns

  • Nethercot, D.A.;Gardner, L.
    • Steel and Composite Structures
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    • 제5권2_3호
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    • pp.127-140
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    • 2005
  • Procedures given in Eurocode 3 Part 1.1 (EN 1993-1-1) for design of the main types of structural member under given systems of loading are presented and described. Whereas some of these e.g. the procedure for axially loaded columns, are little changed from the early concept that appeared more than 25 years ago in the European Recommendations and have subsequently been adopted in many other steel codes of the world, others such as the interaction formulae for beam-columns are new, with aspects of the provisions still under development. For each type of member the basis of the procedure is described and some comparative comments made.

A comparative study of along and cross-wind responses of a tall chimney with and without flexibility of soil

  • Gorski, Piotr;Chmielewski, Tadeusz
    • Wind and Structures
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    • 제11권2호
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    • pp.121-135
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    • 2008
  • The paper is concerned with a comparative study of both the along and cross-wind responses of a tall industrial chimney with and without flexibility of soil. The along-wind response has been estimated by means of approaches presented in three Standards: the Polish, the ISO and the Eurocode and by random vibration approach which is outlined below. The cross-wind response has been estimated by means of the three models developed by Vickery and Basu, Ruscheweyh and Flaga and methods presented in Standards: the Polish, the ISO and the Eurocode (Approach 1 and 2). Computer programmes were developed to obtain estimates of responses of a six-flue, 250 m-tall chimney. The analytical results computed according to the methods presented in different standards and random vibration approaches have been compared. Some unexpected conclusions have been observed.

화재시 온도증가로 인한 RC 슬래브의 강도 특성 (Strength Properties of RC Slabs under Elevated Temperatures from Fire)

  • 임초롱;정철헌;김유석
    • 한국안전학회지
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    • 제25권4호
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    • pp.48-60
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    • 2010
  • The fire resistance performance of 2 RC slabs after exposure to the ISO-834 fire standard without loading has been experimentally investigated. A Comparison is made of the fire resistance performance between RC slabs without PP(polypropylene) fibers and RC slabs with PP fibers. From the fire test results, the presence of PP fibers in RC slabs can reduce spalling and enhance their fire resistance. Until now, the determination of fire resistance of reinforced concrete(RC) slabs has essentially been based on tabulated data. According to ACI 216 code and EUROCODE 2, the design of concrete structures is essentially based on tabulated data for appropriate concrete cover and various fire durations. From the comparison between fire test results and codes, current fire design provisions of codes such as the ACI 216 and the EUROCODE 2 are unconservative for estimating mechanical properties of RC slabs at elevated temperatures.

역량스펙트럼 및 에너지분석을 이용한 RC교각의 내진성능평가에 관한 연구 (Seismic Performance Evaluation of RC Bridge Piers using Capacity Spectrum and Energy Analysis)

  • 정영수;박종협
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2001년도 춘계학술대회 논문집
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    • pp.361-367
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    • 2001
  • This research aims at evaluating the seismic performance of the R/C bridge piers, which were seismically designed in accordance with the seismic provision of limited ductile behavior of Eurocode 8. Pseudo dynamic test for six(6) circular RC bridge piers has been carried out so at to investigate their seismic performance subjected to experted artificial earthquake motions. The objective of this experimental study is to investigate the hysteretic behavior of reinforced concrete bridge piers. Important test parameters are confinement steel ratio, input ground motion, etc. The seismic behavior of circular concrete piers under artificial ground motions has been evaluated through displacement ductility, energy analysis, capacity spectrum. It can be concluded that RC bridge piers designed in the seismic code of limited ductile behavior of Eurocode 8 have been determined to show good seismic performance even under expected artificial earthquakes in moderate seismicity region.

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온도상승에 따른 압축을 받는 냉간성형 C-형강 기둥의 국부 및 전체 좌굴 (Local & Overall Buckling of Cold-Formed Channel Column under Compression at Elevated Temperatures)

  • 백태순;강문명
    • 한국공간정보시스템학회:학술대회논문집
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    • 한국공간정보시스템학회 2004년도 춘계 학술발표회 논문집 제1권1호(통권1호)
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    • pp.63-72
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    • 2004
  • This paper is developed a computer program to analysis the elastic local and overall buckling stress based on Eurocode 3 Part 1.3 for the flange and web, and Euler equations for columns of cold-formed channel under compression at elevated temperatures. The high temperature stress-strain relationships of steel used this paper are determined according to Eurocode 3 Part 1.2. Critical temperatures and the elastic local buckling stresses of the cold-formed channel columns under compression at elevated temperatures are analysed by the computer program developed in this study. Analysis examples are given to show the applicability of the computer program developed in this study.

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Dynamic analysis of steel frames with semi-rigid connections

  • Zohra, Djouaher Fatma;Nacer, Ihaddoudene Touati Abd
    • Structural Engineering and Mechanics
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    • 제65권3호
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    • pp.327-334
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    • 2018
  • In the steel structures design, beam-to-column connections are usually considered either rigid or pinned, while their actual behavior lies between these two ideal cases. This consideration has a major influence on the results of the local and the global behavior of steel structures. This influence is noticed in the case of a static analysis, and has an important effect in the case of a dynamic analysis. In fact, pinned and rigid nodes can be considered as two specific cases of a semi-rigid behavior. To study the efficiency of the classification adopted in Eurocode 3, a numerical simulation of semi-rigid nodes has been carried out using the software ANSYS. In the aim to validate this simulation, the numerical results are compared to those of an analytical approach. After that, the validated numerical simulation has been used, to evaluate the efficiency of the classification adopted by the Eurocode 3, regarding semi-rigid connections. Finally, a new method is proposed to define a more accurate evaluation about semi-rigid connections.

콘크리트 플로 테이블 테스트를 활용한 압송성 검토 방법 (Review Methods of Pumping Effciency using the Concrete flow Table Test)

  • 권해원;공민호;김봉섭;유종진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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    • pp.9-10
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    • 2016
  • This study is purposed to review the confirm method of pumping efficiency using the concrete flow table test in Korea environment. This test method is registered as the "EN 12350-5, Testing fresh concrete. Flow table test" in Eurocode. When applying this test in the Korea construction environment, we reviewed that reasonably apply on the Korean construction Environment. As a result, test results analysis showed that the reality looks a big difference. Its cause is believed to be due to the shape of coarse & fine aggregate. But it will be better predict method, through the correlation analysis of construction data and the standard(Placing Concrete by pumping Methods(ACI Manual of concrete Practice 304.2R-96)).

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Critical review of the EC8 design provisions for buildings with eccentric braces

  • Bosco, Melina;Marino, Edoardo M.;Rossi, Pier Paolo
    • Earthquakes and Structures
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    • 제8권6호
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    • pp.1407-1433
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    • 2015
  • The objections raised by researchers to the design provisions reported in Eurocode 8 make the efficient seismic performance of the eccentrically braced structures designed according to this code unlikely. Given the rationality and the number of the objections, this paper aims to summarize the criticism of researchers and report the opinion of the Authors. The objections raised to the design procedure of eccentrically braced structures regard aspects common to the design of steel structures and aspects specifically related to the design of eccentrically braced structures. The significance of these objections is also shown by means of exemplary cases.