• 제목/요약/키워드: pier-type

검색결과 93건 처리시간 0.022초

응답면 기법을 이용한 잔교식 안벽의 신뢰성 해석 (Reliability Analysis of Pile Type Quaywall Using Response Surface Method)

  • 이상근;김동현
    • 한국해안·해양공학회논문집
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    • 제23권6호
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    • pp.407-413
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    • 2011
  • 응답면 기법을 사용하여 잔교식 안벽의 신뢰성 해석을 수행하였다. 잔교식 안벽은 중력식 안벽과 달리 상부가 강관파일에 의해 지지되는 유연구조물로 한계상태함수가 음함수로 존재한다. 따라서, 한계상태함수를 양함수로 근사하기 위해 응답면 기법을 사용하였다. 응답면 기법을 이용한 LevelII신뢰성해석 방법을 통해 지진하중에 의한 잔교식 안벽의 신뢰도지수를 계산하고, 중요도 추출법을 통해 검증하였다. 수치해석으로는 직항식, 사항식을 각각 해석하였다.

실증시험을 통한 강관주기초의 거동특성 (Behavior of Single Pole Foundation using Experimental Study)

  • 김대홍;오기대
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 추계 학술발표회
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    • pp.598-604
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    • 2010
  • The drilled pier foundation is widely used to support transmission line structures due to its simplicity of construction. When this foundation type is used in conjunction with a single shaft or H-frame structure, it is subjected to a high overturning moment, combined with modest vertical and shear loads. Since the length and diameter of drilled piers are often governed by a maximum permissible deflection, many drilled piers being installed today are very conservatively designed. In this study, Nine prototype field-tests (1/8 scale) have been conducted in order to determine the vertical and lateral resistance of drilled pier foundation for single pole structures. These test results reveal the test piers behaved essentially as rigid bodies in soil (6D) and the center of rotation of the pier were typically 0.6~0.4 of the pier depth below ground surface. Test results also show the relationship between the applied load and the deflection at the top of the pier is highly nonlinear.

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강관주 철탑기초의 수평거동에 관한 실험적 연구 (Experimental Study on the Laterally Loaded Behavior of Single Pole Foundation)

  • 김대홍;김경열
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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    • pp.1087-1094
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    • 2008
  • The drilled pier foundation is widely used to support transmission line structures due to its simplicity of construction. When this foundation type is used in conjunction with a single shaft or H-frame structure, it is subjected to a high overturning moment, combined with modest vertical and shear loads. Since the length and diameter of drilled piers are often governed by a maximum permissible deflection, many drilled piers being installed today are very conservatively designed. In this study, Five prototype field-tests (1/8 scale) have been conducted in order to determine the lateral resistance of drilled pier foundation for single pole structures. These test results reveal the test piers behaved essentially as rigid bodies in soil (6D) and the center of rotation of the pier were typically 0.6~0.4 of the pier depth below ground surface. Test results also show the relationship between the applied load and the deflection at the top of the pier is highly nonlinear.

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매스콘크리트 교각의 수화열에 의한 온도 및 응력 거동에 대한 3차원 유한요소 해석 (A 3-dimensional Finite Element analysis of the Temperature and Stress Development in Mass Concrete Pier due to Heat of Hydration)

  • 주영춘;김은겸;신치범
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 가을 학술발표대회 논문집(III)
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    • pp.928-933
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    • 1998
  • The temperature and stress behaviour of mass concrete pier at early ages was analysed based on the finite element method. The pier investigated is a three-dimensional structure of which the cross-sectional shape varies from a circle to an ellipsoid along the longitudinal axis. In order to obtain the transient temperature and stress distributions in the structure, a three dimensional method was adopted, because the structure of this type cannot be modeled accurately by a two-dimensional method. Temperature analysis was performed by taking into consideration of the cement type and content, boundary and environment conditions including the variations of atmospheric temperature and wind velocity. The results of this study may be useful for the temperature control to restrain thermal cracking and the construction management to design the resonable curing method of mass concrete structure.

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생애주기비용을 이용한 잔교식 안벽의 신뢰도지수 최적화 (Reliability Index Optimization for Pier Type Quay Walls Using Life Cycle Cost)

  • 김동현;윤길림
    • 한국해안·해양공학회논문집
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    • 제23권6호
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    • pp.422-428
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    • 2011
  • 잔교식 안벽의 생애주기비용(Life Cycle Cost, LCC)을 이용하여 신뢰도지수의 최적값을 구하였다. 응답면 기법을 이용한 신뢰성해석을 통해 횡잔교와 돌제식 잔교의 파괴확률을 산정하였다. 파괴확률은 잔교의 파괴 시 복구비용을 산출하는데 활용하였으며 초기공사비와 유지관리비를 모두 고려한 LCC를 최소화시킬 수 있는 신뢰도지수를 찾았다. 지진하중과 접안하중에 대한 다양한 조건에서의 최적 신뢰도지수를 구하였고 이를 통해 신뢰성설계에 사용할 수 있는 목표신뢰도지수를 제안하였다.

Seismic performances of steel reinforced concrete bridge piers

  • Deng, Jiangdong;Liu, Airong;Yu, Qicai;Peng, Guoxing
    • Steel and Composite Structures
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    • 제21권3호
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    • pp.661-677
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    • 2016
  • The quasi static test of the steel reinforced concrete (SRC) bridge piers and rigid frame arch bridge structure with SRC piers was conducted in the laboratory, and the seismic performance of SRC piers was compared with that of reinforced concrete (RC) bridge piers. In the test, the failure process, the failure mechanism, hysteretic curves, skeleton curves, ductility coefficient, stiffness degradation curves and the energy dissipation curves were analyzed. According to the $M-{\Phi}$ relationship of fiber section, the three-wire type theoretical skeleton curve of the lateral force and the pier top displacement was proposed, and the theoretical skeleton curves are well consistent with the experimental curves. Based on the theoretical model, the effects of the concrete strength, axial compression ratio, slenderness ratio, reinforcement ratio, and the stiffness ratio of arch to pier on the skeleton curve were analyzed.

지진 시 지반개량에 따른 잔교식 안벽의 동적 거동 (Dynamic Behavior of Pier-Type Quay Walls Due to Ground Improvement During Earthquakes)

  • 윤현수;윤성규;강기천
    • 한국지반신소재학회논문집
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    • 제23권2호
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    • pp.29-42
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    • 2024
  • 2017년 포항지진으로 인해 액상화 현상에 의한 안벽구조물에 피해가 발생하였다. 액상화는 지진 시 과잉간극수압 증가로 인해 유효응력이 소실되어 발생하게 된다. 이에 따른 잔교식 안벽의 피해 발생 부분을 규명하며 액상화로 인한 피해를 분석하였다. 또한 개량지반의 경우 연암층과 강성차이로 인해 하부 Sand 층의 액상화 현상으로 인해 피해가 발생하여, 비액상화 지반으로 가정하고 추가적인 수치해석을 수행하였다. 과잉간극수압비의 증가에 영향을 주는 요인으로는 지반의 상대밀도 및 입력 지진가속도의 크기 등 여러 가지 원인이 있다. 따라서 본 연구는 입력가속도의 크기를 증가시켜 Case 1~3에 대해 수치해석을 수행하였고, 개량지반의 경우 하부 Sand층의 액상화 현상으로 인한 피해가 발생하여 비액상화지반으로 가정하여 분석을 수행하였다. 결과적으로, 개량지반은 하부 액상화지반이 있을 경우 추가적인 보강이 필요하며, 잔교식 안벽 말뚝의 수평변위가 약 2배 감소하는 현상이 나타났다.

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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Seismic behavior of thin-walled CFST pier-to-base connections with tube confined RC encasement

  • Xuanding Wang;Yue Liao;Jiepeng Liu;Ligui Yang;Xuhong Zhou
    • Steel and Composite Structures
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    • 제50권2호
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    • pp.217-235
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    • 2024
  • Concrete-filled steel tubes (CFSTs) nowadays are widely used as the main parts of momentous structures, and its connection has gained increasing attention as the complexity in configuration and load transfer mechanism. This paper proposes a novel CFST pier-to-footing incorporating tube-confined RC encasement. Such an innovative approach offers several benefits, including expedited on-site assembly, effective confinement, and collision resistance and corrosion resistance. The seismic behavior of such CFST pier-to-footing connection was studied by testing eight specimens under quasi-static cyclic lateral load. In the experimental research, the influences on the seismic behavior and the order of plastic hinge formation were discussed in detail by changing the footing height, axial compression ratio, number and length of anchored bars, and type of confining tube. All the specimens showed sufficient ductility and energy dissipation, without significant strength degradation. There is no obvious failure in the confined footing, while local buckling can be found in the critical section of the pier. It suggests that the footing provides satisfactory strength protection for the connection.

노후 잔교식 부두의 동적구조 안전성 평가에 관한 연구 (Evaluation of Dynamic Structural Safety of Aged Finger Pier)

  • 이성우;이상호;지기환
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1993년도 봄 학술발표회논문집
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    • pp.45-52
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    • 1993
  • Evaluation of structural stability of aged wharf structure of pier type is of great importance for both safety and rehabilitation, Series of field dynamic experiments were performed for berthing impact and the results were used to calibrate analysis model. Through dynamic analysis for design, berthing impact safety of old wharf structure were evaluated. In this paper the procedure and results of experiments and analysis are presented.

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