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Infl uence of structural parameters on dynamic characteristics and wind-induced buffeting responses of a super-long-span cable-stayed bridge

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Earthquake Engineering and Engineering Vibration 2014年第3期13卷 389-399页

作者： Wang Hao Chen Chunchao Xing Chenxi Li Aiqun Key Laboratory of Concrete & Prestressed Concrete Structures of Ministry of Education Southeast University Dept. of Civil and Environmental Engineering Virginia Tech Blacksburg VA 24061 USA PhD Candidate

A 3D finite element （FE） model for the Sutong cable-stayed bridge （SCB） is established based on ANSYS. The dynamic characteristics of the bridge are analyzed using a subspace iteration method. Based on recorded wind data, the measured spectra expression is presented using the nonlinear least-squares regression method. Turbulent winds at the bridge site are simulated based on the spectral representation method and the FFT technique. The influence of some key structural parameters and measures on the dynamic characteristics of the bridge are investigated. These parameters include dead load intensity, as well as vertical, lateral and torsional stiffness of the steel box girder. In addition, the influence of elastic stiffness of the connection device employed between the towers and the girder on the vibration mode of the steel box girder is investigated. The analysis shows that all of the vertical, lateral and torsional buffeting displacement responses reduce gradually as the dead load intensity increases. The dynamic characteristics and the structural buffeting displacement response of the SCB are only slightly affected by the vertical and torsional stiffness of the steel box girder, and the lateral and torsional buffeting displacement responses reduce gradually as the lateral stiffness increases. These results provide a reference for dynamic analysis and design of super-long-span cable-stayed bridges.

关键词： cable-stayed bridge dynamic characteristics finite element (FE) method wind field simulation buffetingresponse parameter effects elastic connection device

Dynamic performance of cable-stayed bridge tower with multi-stage pendulum mass damper under wind excitations——I:Theory

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Earthquake Engineering and Engineering Vibration 2007年第4期6卷 295-306页

作者：郭安薪徐幼麟李惠 School of Civil Engineering Harbin Institute of Technology Harbin 150090 China Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hung Hom Hong Kong China

In this paper, wind-induced vibration control of a single column tower of a cable-stayed bridge with a multi- stage pendulum mass damper （MSPMD） is investigated. Special attention is given to overcoming space limitations for installing the control device in the tower and the effect of varying natural frequency of the towers during construction. First, the finite element model of the bridge during its construction and the basic equation of motion of the MSPMD are introduced. The equation of motion of the bridge with the MSPMD under along-wind excitation is then established. Finally, a numerical simulation and parametric study are conducted to assess the effectiveness of the control system for reducing the wind-induced vibration of the bridge towers during construction. The numerical simulation results show that the MSPMD is practical and effective for reducing the along-wind response of the single column tower, can be installed in a small area of the tower, and complies with the time-variant characteristics of the bridge during its entire construction stage.

关键词： multi-stage pendulum mass damper cable-stayed bridge single column tower wind-induced vibration

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Seismic experimental study on a concrete pylon from a typical medium span cable-stayed bridge

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Frontiers of Structural and Civil Engineering 2018年第3期12卷 401-411页

作者： Yan XU Shijie ZENG Xinzhi DUAN Dongbing JI State Key Laboratory for Disaster Reduction in Civil Engineering Tongji University Shanghai 200092 China i University Shanghai 200092 China Shanghai Municipal Planning and Design Research Institute Shanghai 200031 China Jiangsu Province Communications Planning and Design Institute Limited Company Nanjing 210014 China

According to the current seismic design codes of bridges in China, cable-stayed bridges have been usually required to remain elastic even subjected to strong earthquakes. However, the possibilities of pylon plastic behavior were revealed in recent earthquake damages. The lack of due diligence in the nonlinear seismic behavior of the pylon has caused a blurry understanding about the seismic performance of such widely built though less strong earthquake experienced structures. In light of this point, a 1/20 scaled concrete pylon model which from a typical medium span cable-stayed bridge was designed and tested on the shaking table longitudinally. The dynamic response and seismic behavior of the pylon were measured, evaluated and compared to reveal its vulnerable parts and nonlinear seismic performance. The results show that most parts of the concrete pylon remain elastic even under very strong excitations, which means a sufficient safety margin for current pylon longitudinal design. The most vulnerable parts of the pylon appeared first at the pylon bottom region, cracks opening and closing at the pylon bottom were observed during the test, and then extended to the lower column and middle column around the lower strut.

关键词： cable-stayed bridge pylon shaking table test seismic behavior

Numerical calculation on solar temperature field of a cable-stayed bridge with U-shaped section on high-speed railway

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Journal of Central South University 2014年第8期21卷 3345-3352页

作者：刘文硕戴公连饶少臣 School of Civil Engineering Central South University China Railway Siyuan Survey and Design Group Co.Ltd.

Based on transient temperature field theory of heat conduction, the solar temperature field calculation model of U-shape sectioned high-speed railway cable-stayed bridge under actions of concrete beams and ballast was established. Using parametric programming language, finite element calculation modules considering climate conditions, bridge site, structure dimension and material thermophysical properties were compiled. Six standard day cycles with the strongest yearly radiation among the bridge sites were selected for sectional solar temperature field calculation and temperature distributions under different temperature-sensitive parameters were compared. The results show that under the influence of sunshine, U-shape section of the beam shows obvious nonlinear distribution characteristics and the maximum cross-section temperature difference is more than 21℃; the ballast significantly reduces sunshine temperature difference of the beam and temperature peak of the bottom margin lags with the increase of ballast thickness; the maximum cross-section vertical temperature gradient appears in summer while large transverse temperature difference appears in winter.

关键词： high-speed railway cable-stayed bridge U-shaped section solar temperature field thermal analysis

Numerical and Experimental Study of Free Vibration Characteristics of a cable-stayed bridge

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Journal of China University of Geosciences 2006年第2期17卷 185-188页

作者：资建民王元汉朱宏平 School of Civil Engineering and Mechanics Huazhong University of Science and Technology

The main aim of this study is to understand the dynamic behavior of a cable-stayed bridge, using both numerical and experimental analysis. A three-dimensional finite element model for the bridge was developed for the free vibration analysis and the ambient vibration properties of the bridge were determined through field testing. The experimental and numerical results of natural frequencies and the associated mode shapes were compared, and the high accuracy between them shows that the 3D model is capable of approximately representing the dynamic behavior of the bridge and the use of ambient vibration survives in future testing of the bridge. These dynamic characteristics can be used as the basis for updating the finite element model and also for global damage detection.

关键词： cable-stayed bridge ambient vibration test dynamic behavior.

Influence of Girder Vibration on cable Damper's Performance of A cable-stayed bridge

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Journal of Harbin Institute of Technology(New Series) 2014年第1期21卷 109-114页

作者： Dong Liang Yong Chen Dept. of Civil Engineering Hebei University of Technology Civil Engineering Technology Research Center of Hebei Province Dept. of Civil Engineering Zhejiang University

The model combined by cable,girder and damper is founded to study the influence of girder vibration on cable damper 's performance of a cable-stayed bridge. The complex mode method and nondimensionalization are used to analyze the relationship between the girder's parameters and the performance of cable-related damper. The results indicate that the performance of cable-related damper will decrease greatly when the girder frequencies are near the frequencies of cable. The smaller absolute displacement of damper's piston caused by the very small vibration phase shift of girder and cable is the physical cause of the negative impact mentioned above.

关键词： cable-stayed bridge vibration mitigation of cable girder vibration modal damping complex mode method cause analysis

Theoretical and experimental study on shear lag effect of partially cable-stayed bridge

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第8期6卷 875-877页

作者：吴高峰徐鸿 Mechanical and Electrical Engineering College Beijing University of Chemical Technology Beijing 100029 China

In order to resolve the traffic congestion problem, many cable-stayed bridges are designed with a large width to span ratio. This results in significant shear lag effect to cause nonuniform stress distribution along the flanges of the beam of bridge. This paper reports study on the shear lag effect of the Lanzhou Xiaoxihu Yellow River bridge. A 3D finite element model of the bridge was developed and finite element analysis (FEA) was done to obtain the theoretical results. To evaluate the theoretical results, a scaled model was made to conduct static test in laboratory. The experiment results accorded with the results obtained by FEA. It is proved that FEA is an effective method to predict shear lag effect of bridges of this type.

关键词： cable-stayed bridge FEA Experimental Shear lag effect

Application of Gliding Scaffold System In cable-stayed bridge Construction

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Journal of China University of Mining and Technology 2005年第2期15卷 152-156页

作者： YUBao-chu ZHANGZhe ChangFu-ping Instituteofbridgeengineering DalianUniversityofTechnologyDalianLiaohing116023China

Gonghe bridge is a double level cable-stayed concrete bridge with a single-cable-plane of single cable tower. Its span is 114+120 m and a whole length of 236 m. The gliding scaffold equipment is used for the first time in the long span cable-stayed bridge construction to reduce the construction time limit. In the process of construction, to make sure a safe connection among concrete objects with different ages, the single-supporting and single-suspension system is adopted before the concrete pouring. While the double-supporting and single-suspension system is applied after con- crete pouring. These construction systems with gliding scaffold equipment are first introduced in long span ca- ble-stayed bridge and presented in detail[1]. The practice shows that these gliding scaffold systems have many advan- tages over the traditional ones.

关键词： cable-stayed bridge gliding scaffolding equipment construction monitor and control

Dynamic analysis and modal test of long-span cable-stayed bridge based on ambient excitation

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Journal of Central South University of Technology 2007年第1期14卷 135-139页

作者：陈常松颜东煌 School of bridge and Structure Engineering Changsha University of Science and Technology

To study the stiffness distribution of girder and the method to identify modal parameters of cable-stayed bridge, a simplified dynamical finite element method model named three beams model was established for the girder with double ribs. Based on the simplified model four stiffness formulae were deduced according to Hamilton principle. These formulae reflect well the contribution of the flexural, shearing, free torsion and restricted torsion deformation, respectively. An identification method about modal parameters was put forward by combining method of peak value and power spectral density according to modal test under ambient excitation. The dynamic finite element method analysis and modal test were carried out in a long-span concrete cable-stayed bridge. The results show that the errors of frequencies between theoretical analysis and test results are less than 10% mostly, and the most important modal parameters for cable-stayed bridge are determined to be the longitudinal floating mode, the first vertical flexural mode and the first torsional mode, which demonstrate that the method of stiffness distribution for three beams model is accurate and method to identify modal parameters is effective under ambient excitation modal test.

关键词： bridge engineering cable-stayed bridge dynamic finite element method ambient excitation modal test