• 제목/요약/키워드: concrete cable-stayed bridge

검색결과 89건 처리시간 0.024초

Vibration reduction design of the Hangzhou Bay cable-stayed bridges

  • Liu, Weiqing;Xu, Xiuli;Wang, Rengui;Wang, Zijun;Wu, Xiaolan
    • Structural Engineering and Mechanics
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    • 제24권3호
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    • pp.339-354
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    • 2006
  • Hangzhou Bay Bridge spans the Hangzhou Bay and is located at Zhejiang province in the southeast seacoast of China. The total length of the bridge is 36 km. The bridge is composed of bridge approaches made up of multi-span prestressed concrete box girders and two cable-stayed bridges over the north and south navigable spans respectively. The seismic response analysis of the bridge model shows that if the navigable spans are designed as the routine earthquake-resistance system, the displacements and internal forces in pylons, piers and deckes are too large to satisfy the anti-seismic requirement of the structure. Therefore, the seismic reduction design was carried out by using viscous dampers to dissipate the kinetic energy of the structure both longitudinally and transversely. Using the vibration reduction system and aiming at the reasonable optimal goal, the purpose to reduce the seismic responses in south and north navigable spans has been achieved.

Structural health monitoring data reconstruction of a concrete cable-stayed bridge based on wavelet multi-resolution analysis and support vector machine

  • Ye, X.W.;Su, Y.H.;Xi, P.S.;Liu, H.
    • Computers and Concrete
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    • 제20권5호
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    • pp.555-562
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    • 2017
  • The accuracy and integrity of stress data acquired by bridge heath monitoring system is of significant importance for bridge safety assessment. However, the missing and abnormal data are inevitably existed in a realistic monitoring system. This paper presents a data reconstruction approach for bridge heath monitoring based on the wavelet multi-resolution analysis and support vector machine (SVM). The proposed method has been applied for data imputation based on the recorded data by the structural health monitoring (SHM) system instrumented on a prestressed concrete cable-stayed bridge. The effectiveness and accuracy of the proposed wavelet-based SVM prediction method is examined by comparing with the traditional autoregression moving average (ARMA) method and SVM prediction method without wavelet multi-resolution analysis in accordance with the prediction errors. The data reconstruction analysis based on 5-day and 1-day continuous stress history data with obvious preternatural signals is performed to examine the effect of sample size on the accuracy of data reconstruction. The results indicate that the proposed data reconstruction approach based on wavelet multi-resolution analysis and SVM is an effective tool for missing data imputation or preternatural signal replacement, which can serve as a solid foundation for the purpose of accurately evaluating the safety of bridge structures.

FBG 센서를 이용한 사장교 초기재령 특성 모니터링 연구 (Monitoring of Early-age Behavior of concrete cable-stayed girder bridge by FBG sensors)

  • 장일영;박승민;김성겸;양재열;박준영
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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    • pp.105-106
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    • 2010
  • 본 연구에서는 대구 사장교 건설현장에 FBG 온도센서와 변형률 센서를 설치하여 콘크리트 타설 초기의 온도와 변형률을 모니터링을 실시하였으며, 이 연구에서 사용된 모니터링 기법은 매우 유용한 방법으로 실용화 될 수 있을 것으로 기대된다.

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부분 인장형 사장교 주형의 복합 구조 (Hybrid Deck System for Partially Earth Anchored Cable Stayed Bridges)

  • 조재영;노정휘;김정중
    • 복합신소재구조학회 논문집
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    • 제4권4호
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    • pp.30-36
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    • 2013
  • Partially earth anchored (PEA) can improve the structural safety and economic feasibility of multiple span cable stayed bridge (CSB). The PEA-CSB can restrain axial compressive load acting on a tower and reduce the global buckling length of a stiffened girder. For these reasons, structural members subject to axial forces can be effectively utilized and material quantity required for a steel deck can be reduced to save construction cost. In this study, the PEA system was verified for its application on a multiple span CSB. The CSB is a four-tower multi-span bridge which has a main span length of 500 m. As high tensile stress was generated at the top of the bridge decks at the mid-span between two main columns, a hybrid deck system for enhancing the bridge deck sections was proposed. While the composite sections made of concrete and steel were used near to the main columns, steel sections were used at the mid-span between two main columns.

2주탑 콘크리트 사장교의 주요 부재 지진 취약도 분석 (Seismic Fragility Analysis by Key Components of a Two-pylon Concrete Cable-stayed Bridge)

  • 신연우;홍기남;권용민;연영모
    • 한국구조물진단유지관리공학회 논문집
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    • 제24권4호
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    • pp.26-37
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    • 2020
  • 본 연구에서는 2주탑 콘크리트 사장교를 모델링하고 취약부재에 대한 비탄성 시간이력해석 결과들로부터 설계기준과 재료특성을 반영한 취약도 분석을 수행하여 콘크리트 사장교에 적합한 취약도 분석을 제시하고자 한다. 사장교의 지진 취약도 곡선을 작성하기 위해 사장교의 주요 취약부재에 대한 한계상태를 결정하고 비탄성 시간이력해석에 의한 응답값과 비교하여 손상상태를 구분한다. 입력지반운동에 대한 취약부위들의 동적응답이 각 구조부재의 한계상태를 초과할 손상확률을 최대지반가속도(PGA)에 대해 구함으로써 사장교의 지진 취약도 곡선을 작성하였다. 주탑의 취약도 곡선에 의하면 0.5g에서 보통손상상태의 확률이 교축방향의 경우 32%인데 반해 교축직각방향의 경우 7%로 나타나 동일 PGA에서 교축직각방향에 비해 교축방향의 손상확률이 더 높은 것으로 나타났다. 연결부의 지진 취약도 곡선을 보면 심한 손상상태의 손상확률이 다른 부재에 비해 매우 높은 수준을 보였는데 이는 지진에 의한 연결부의 손상이 주탑과 케이블의 손상에 비해 매우 민감하다는 것을 의미한다. 케이블의 지진 취약도 곡선에서는 보통손상상태 등급 이후의 손상확률이 점차 낮아져 완전손상상태에 이를 확률은 2.0g의 큰 지진에서도 30%미만의 확률을 가지는 것으로 나타났다.