• Title/Summary/Keyword: Cable-stayed concrete bridge

Search Result 89, Processing Time 0.026 seconds

Vibration reduction design of the Hangzhou Bay cable-stayed bridges

  • Liu, Weiqing;Xu, Xiuli;Wang, Rengui;Wang, Zijun;Wu, Xiaolan
    • Structural Engineering and Mechanics
    • /
    • v.24 no.3
    • /
    • pp.339-354
    • /
    • 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
    • /
    • v.20 no.5
    • /
    • pp.555-562
    • /
    • 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.

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

  • Jang, Il-Young;Park, Seung-Min;Kim, Seong-Kyum;Yang, Jae-Yeol;Park, Joon-Young
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2010.05a
    • /
    • pp.105-106
    • /
    • 2010
  • FBG temperature sensor and strain sensor has been used to monitoring shrinkage and temperature of concrete cable-stayed girder bridge site in its casting early age, The monitoring method using this study is expected to used a practical method.

  • PDF

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

  • Cho, Jae-Young;Noh, Junghwi;Kim, Jung Joong
    • Journal of the Korean Society for Advanced Composite Structures
    • /
    • v.4 no.4
    • /
    • pp.30-36
    • /
    • 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.

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

  • Shin, Yeon-Woo;Hong, Ki-Nam;Kwon, Yong-Min;Yeon, Yeong-Mo
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.24 no.4
    • /
    • pp.26-37
    • /
    • 2020
  • This study intends to present a fragility analysis method suitable for concrete cable-stayed bridges by performing an analysis reflecting design criteria and material characteristics from the results of inelastic time-history analysis. In order to obtain the fragility curve of the cable-stayed bridge, the limit state of the main component of the cable-stayed bridge is determined, and the damage state is classified by comparing it with the response value based on inelastic time history analysis. The seismic fragility curve of the cable-stayed bridge was made by obtaining the probability of damage to PGA that the dynamic response of the vulnerable parts to input ground motion would exceed the limit state of each structural member. According to the pylon's fragility curve, the probability of moderate damage at 0.5g is 32% for the longitudinal direction, while 7% for the transversal direction, indicating that the probability of damage in the longitudinal direction is higher in the same PGA than in the transversal direction. The seismic fragility curve of the connections showed a very high probability of damage, meaning that damage to the connections caused by earthquakes is very sensitive compared to damage to the pylon and cables. The cable's seismic fragility curve also showed that the probability of complete damage state after moderate damage state gradually decreased, resulting in less than 30% probability of complete damage at 2.0g.