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Simplified design of nonlinear damper parameters and seismic responses for long-span cable-stayed bridges with nonlinear viscous dampers

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1103-1116页

作者： Huihui LI Lifeng LI Rui HU Meng YE College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering Shenzhen UniversityShenzhen 518060China College of Civil Engineering Hunan UniversityChangsha 410082China

Viscous dampers are widely used as passive energy dissipation devices for long-span cable-stayed bridges for mitigation of seismic load-induced ***,complicated finite element(FE)modeling,together with repetitive and computationally intensive nonlinear time-history analyses(NTHAs)are generally required in conventional design *** streamline the preliminary design process,this paper developed a simplified longitudinal double degree of freedom model(DDFM)for single and symmetric twin-tower cable-stayed *** on the proposed simplified longitudinal DDFM,the analytical equations for the relevant mass-and stiffness-related parameters and longitudinal natural frequencies of the structure were derived by using analytical and energy *** of the relationship between the nonlinear viscous damper parameters and the equivalent damping ratio was achieved through the equivalent linearization ***,the analytical equations of longitudinal seismic responses for long-span cable-stayed bridges with nonlinear viscous dampers were *** on the developed simplified DDFM and suggested analytical equations,this paper proposed a simplified calculation framework to achieve a simplified design method of nonlinear viscous damper ***,the effectiveness and applicability of the developed simplified longitudinal DDFM and the proposed calculation framework were further validated through numerical analysis of a practical cable-stayed ***,the results indicated the following.1)For the obtained fundamental period and longitudinal stiffness,the differences between results of the simplified longitudinal DDFM and numerical analysis were only 2.05%and 1.5%,respectively.2)Relative calculation errors of the longitudinal girder-end displacement and bending moment of the bottom tower section of the bridge obtained from the simplified longitudinal DDFM were limited to less than 25%.3)The equivalent damping ratio of nonline

关键词： cable-stayed bridges viscous dampers simplified analytical model equivalent damping ratio seismic mitigation

Modeling of cable vibration effects of cable-stayed bridges

维普期刊数据库评论

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维普期刊数据库

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Earthquake Engineering and Engineering Vibration 2002年第1期1卷 74-85页

作者： S.H.Cheng David T.Lau Department of Civil and Environmental Engineering Carleton UniversityOttawaOntarioCanadaPost-doctoral fellow Department of Civil and Environmental Engineering Carleton UniversityOttawaOntarioCanada Professor

The analysis of dynamic responses of cable-stayed bridges subjected to wind and earthquake loads generally considers only the motions of the bridge deck and *** influence of the stay cable vibration on the responses of the bridge is either ignored or considered by approximate *** transverse vibration of the stay cables,which can be significant in some cases,are usually neglected in previous *** the present study,a new three-node cable element has been developed to model the transverse motions of the *** interactions between the cable behavior and the other parts of the bridge superstructure are considered by the concept of dynamic *** nonlinear effect of the cable caused by its self-weight is included in the *** examples are presented to demonstrate the accuracy and efficiency of the proposed model. The impact of cable vibration behavior on the dynamic characteristics of cable-stayed bridges is discussed.

关键词： cable-stayed bridges cable vibration dynamics finite elements long-span structures

Research development of digital maintenance and management system for long-span cable-stayed bridges

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Journal of Harbin Institute of Technology(New Series) 2009年第1期16卷 96-100页

作者：任远黄侨孙永明 Institute of Bridge Engineering Harbin Institute of Technology Institute of Bridge Engineering Southeast University

Digital cable-stayed bridge maintenance and management system （DCBMS） was developed for the need of maintenance and management of long-span cable-stayed bridges. In this paper, the major functions and theoretical application of eight modules were systematically stated with the background of Harbin Songhua River cable-stayed bridge, which include data management module, inspection and measurement module, assessment module, finite dement analysis module, disease diagnosis and prediction module, maintenance module, query module and help module. By analyzing and calculating the data from manual inspection database, basic database and health monitoring subsystem, DCBMS can accomplish the functions like life prediction, disease diagnosis, comprehensive assessment, maintenance and management of bridges. Therefore, the maintenance and management of long-span cable-stayed bridges can be made digital, professional and scientific. By running this system, a real-time and specific technical guidance can be provided for the maintainers and managers of long- span cable-stayed bridges.

关键词： cable-stayed bridges system development maintenance and management comprehensive assessment disease diagnosis

cable-stayed bridges: 40 Years of Experience Worldwide

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Digital simulation of 3D turbulence wind field of Sutong Bridge based on measured wind spectra

2012年

作者： George F. Elmasry

来源：畅想之星图书光盘版（南... 评论

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畅想之星图书光盘版（南通市图书馆镜像）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第2期13卷 91-104页

作者： Hao WANG Zhou-hong ZONG Ai-qun LI Teng TONG Jie NIU Wen-ping DENG Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education Southeast UniversityNanjing 210096China Key Laboratory of Environmental Impact and Structural Safety in Engineering China University of Mining&TechnologyXuzhou 221116China

Time domain analysis is an essential implement to study the buffeting behavior of long-span bridges for it can consider the non-linear effect which is significant in long-span bridges. The prerequisite of time domain analysis is the accurate description of 3D turbulence winds. In this paper, some hypotheses for simplifying the 3D turbulence simulation of long-span cable-stayed bridges are conducted, considering the structural characteristics. The turbulence wind which is a 3D multivariate stochastic vector process is converted into four independent 1D univariate stochastic processes. Based on recorded wind data from structural health monitoring system (SHMS) of the Sutong Bridge, China, the measured spectra expressions are then presented using the nonlinear least-squares fitting method. Turbulence winds at the Sutong Bridge site are simulated based on the spectral representation method and the Fast Fourier transform (FFT) technique, and the relevant results derived from target spectra including measured spectra and recommended spectra are compared. The reliability and accuracy of the presented turbulence simulation method are validated through comparisons between simulated and target spectra (measured and recommended spectra). The obtained turbulence si-mulations can not only serve further analysis of the buffeting behavior of the Sutong Bridge, but references for structural anti-wind design in adjacent regions.

关键词： Turbulence simulation Spectral representation method Fast Fourier transform (FFT) cable-stayed bridges Struc-tural health monitoring system (SHMS) Power spectral density

STIFFNESS CHARACTERISTICS AND GEOMETRIC CONFIGURATIONS OF cable-SUPPORTED bridges

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STIFFNESS CHARACTERISTICS AND GEOMETRIC CONFIGURATIONS OF CA...

Cross spectral energy method for damage assessment of the cable-stayed bridge under operational conditions

第一届交通运输工程国际学术会议

作者： YANG Decan Department of Road & Bridge Engineering Wuhan University of Technology Wuhan China 430063

The structural stiffness is the ability of a structure to resist the deformation. It is an integrated index and is restrained by many factors. Realising the different effects of these factors on structural stiffness can make the structural forms more reasonable and more optimum. The concept of structural geometric configuration stiffness was proposed in this paper. The structural general stiffness was considered being composed of physical stiffness, section stiffness and geometric configuration stiffness. The stiffness characteristics during the evolution of cable-supported bridges can be discussed by the concept of geometric configuration stiffness. The cable-stayed bridges have stronger stiffness than suspension bridges because of the stronger geometric configuration stiffness. The evolution of the structural forms, especially structural forms of bridges is in fact the changing process of the geometric configuration stiffness.

关键词： cable-supported bridges suspension bridges cable-stayed bridges stiffness characteristic, geometric configuration

来源： cnki会议评论

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cnki会议

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High Technology Letters 2008年第3期14卷 309-315页

作者：杨和振 Li Huajun School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200030 P.R. China College of Engineering Ocean University of China Qingdao 266071 P. R. China

The new cross spectral energy method(CSEM)is proposed for maintaining cable-stayed bridge safe-ty by the measurable output-only vibration *** assessment of real structures is limited by aseries of problems such as unknown ambient excitation forces,errors introduced by system identification,incomplete dynamic measurements,*** the methodology based on cross spectral energy of eachsubstructure member is derived to meet these *** novel damage index does not require anymodal or parameter identification *** can be calculated directly from vibration test *** or-der to evaluate the efficiency of the presented methodology,a three dimensional(3D)actual cable-stayedbridge model with one or more damaged positions under operational conditions was *** order totestify the reliability of damage detection method,the response data was polluted by the random *** proved that the proposed method can successfully localize all damage cases even in noisy *** help of examples,the CSEM can potentially be applied as a nondestructive evaluation technique(NDT)for on-line health monitoring of cable-stayed bridges with minimum disruption of its operations.

关键词： damage assessment structural health monitoring finite element method vibration cable-stayed bridges

Data-driven methods for predicting the representative temperature of bridge cable based on limited measured data

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Journal of Central South University 2024年第9期31卷 3168-3186页

作者： WANG Fen DAI Gong-lian HE Chang-lin GE Hao RAO Hui-ming School of Civil Engineering University of South ChinaHengyang 421001China School of Civil Engineering Central South UniversityChangsha 410074China Southeast Coastal Railway Fujian Co. Ltd.Fuzhou 350013China

cable-stayed bridges have been widely used in high-speed railway *** accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and maintenance of cable-stayed ***,the representative temperatures of stayed cables are not specified in the existing design *** address this issue,this study investigates the distribution of the cable temperature and determinates its representative ***,an experimental investigation,spanning over a period of one year,was carried out near the bridge site to obtain the temperature *** to the statistical analysis of the measured data,it reveals that the temperature distribution is generally uniform along the cable cross-section without significant temperature ***,based on the limited data,the Monte Carlo,the gradient boosted regression trees(GBRT),and univariate linear regression(ULR)methods are employed to predict the cable’s representative temperature throughout the service *** methods effectively overcome the limitations of insufficient monitoring data and accurately predict the representative temperature of the ***,each method has its own advantages and limitations in terms of applicability and accuracy.A comprehensive evaluation of the performance of these methods is conducted,and practical recommendations are provided for their *** proposed methods and representative temperatures provide a good basis for the operation and maintenance of in-service long-span cable-stayed bridges.

关键词： cable-stayed bridges representative temperature gradient boosted regression trees(GBRT)method field test limited measured data

DAMAGE ANALYSIS AND LOCATION OF RUNYANG BRIDGE USING MULTI-LAYER PERCEPTRON

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Transactions of Nanjing University of Aeronautics and Astronautics 2008年第1期25卷 67-73页

作者：杨杰李爱群李兆霞南京航空航天大学航空宇航学院东南大学土木工程学院

A damage location method using multi-layer perceptron （MLP） is developed to diagnose the cable damage of a real long span cable-stayed bridge. Firstly, the damage patterns are defined based on dynamical calculation. The analysis of damage pattern reveals that the damage patterns caused by different damage locations have inherent distinctness, while the damage extent only linearly amplifies the damage pattern curves. And 4th, 6th and 7th order frequencies are canceled from the patterns because of their insensitiveness to cable damage. Then a MLP network is designed by trail-error method to describe the 7-D mapping space of damage pattern. Identification results prove that the properly organized MLP can grasp the damage pattern and identify the damage location.

关键词： cable-stayed bridges neural networks damage detection pattern recognition