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Earthquake Engineering and Engineering Vibration 2021年第4期20卷 1021-1032页

作者： Li Yafeng Li Shouying chen zhengqing Key Laboratory for Wind and Bridge Engineering of Hunan Province College of Civil EngineeringHunan UniversityChangsha 410082China

The optimal design and effectiveness of three control systems,tuned viscous mass damper(TVMD),tuned inerter damper(TID)and tuned mass damper(TMD),on mitigating the seismic responses of base isolated structures,were systematically ***,the seismic responses of the base isolated structure with each control system under white noise excitation were ***,the structural parameter optimizations of the TVMD,TID and TMD were conducted by using three different *** results show that the three control systems were all effective in minimizing the root mean square value of seismic responses,including the base shear of the BIS,the absolute acceleration of structural SDOF,and the relative displacement between the base isolation floor and the ***,considering the superstructure as a structural MDOF,a series of time history analyses were performed to investigate the effectiveness and activation sensitivity of the three control systems under far field and near fault seismic *** results show that the effectiveness of TID and TMD with optimized parameters on mitigating the seismic responses of base isolated structures increased as the mass ratio increases,and the effectiveness of TID was always better than TMD with the same mass *** TVMD with a lower mass ratio was more efficient in reducing the seismic response than the TID and ***,the TVMD,when compared with TMD and TID,had better activation sensitivity and a smaller stroke.

关键词： base isolated structure inerter optimal design seismic response vibration control

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Feasibility study of a large-scale tuned mass damper with eddy current damping mechanism

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 391-401页

作者： Wang Zhihao chen zhengqing Wang Jianhui Wind Engineering Research Center Hunan UniversityChangsha 410082China School of Civil Engineering and Communication North China University of Water Resources and Electric PowerZhengzhou 450011China

Tuned mass dampers （TMDs） have been widely used in recent years to mitigate structural vibration. However, the damping mechanisms employed in the TMDs are mostly based on viscous dampers, which have several well-known disadvantages, such as oil leakage and difficult adjustment of damping ratio for an operating TMD. Alternatively, eddy current damping （ECD） that does not require any contact with the main structure is a potential solution. This paper discusses the design, analysis, manufacture and testing of a large-scale horizontal TMD based on ECD. First, the theoretical model of ECD is formulated, then one large-scale horizontal TMD using ECD is constructed, and finally performance tests of the TMD are conducted. The test results show that the proposed TMD has a very low intrinsic damping ratio, while the damping ratio due to ECD is the dominant damping source, which can be as large as 15% in a proper configuration. In addition, the damping ratios estimated with the theoretical model are roughly consistent with those identified from the test results, and the source of this error is investigated. Moreover, it is demonstrated that the damping ratio in the proposed TMD can be easily adjusted by varying the air gap between permanent magnets and conductive plates. In view of practical applications, possible improvements and feasibility considerations for the proposed TMD are then discussed. It is confirmed that the proposed TMD with ECD is reliable and feasible for use in structural vibration control.

关键词： tuned mass damper eddy current damping permanent magnets conductive plate modal damping ratio

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Time-domain and frequency-domain approaches to identification of bridge flutter derivatives

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Frontiers of Structural and Civil Engineering 2009年第2期3卷 173-179页

作者： zhengqing chen Wind Engineering Research Center Hunan UniversityChangsha 410083China

Flutter derivatives are essential for flutter analysis of long-span bridges,and they are generally identified from the vibration testing data of a sectional model suspended in a wind *** use of the forced vibration testing data of three sectional models,namely,a thin-plate model,a nearly streamlined model,and a bluff-body model,a comparative study was made to identify the flutter derivatives of each model by using a time-domain method and a frequency-domain *** was shown that all the flutter derivatives of the thin-plate model identified with the frequency-domain method and time-domain method,respectively,agree very ***,some of the flutter derivatives of each of the other two models identified with the two methods deviate to some *** precisely,the frequency-domain method usually results in smooth curves of the flutter *** formulation of time-domain method makes the identification results of flutter derivatives relatively sensitive to the signal phase lag between vibration state vector and aerodynamic forces and also prone to be disturbed by noise and nonlinearity.

关键词： long-span bridges wind-induced vibration flutter derivatives forced vibration test time-domain method frequency-domain method

Simultaneous Al2O3 Doping and Sulfation in Hierarchically Porous ZrO2 Solid Acids by an One-pot Synthesis for Enhanced Recycling Catalytic Performances

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Chinese Journal of Chemistry 2011年第3期29卷 483-488页

作者： Wang, Nan chen, Yu Ye, zhengqing chen, Hangrong Shi, Jianlin State Key Lab of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

Alumina doping and sulfation in hierarchically porous zirconia solid acids have been achieved simultaneously via one-pot and bi-surfactant-assisted self-assembly process, using aluminum sulfate as both Al and SO^2- sources. The prepared composite solid acids showed much enhanced acidity and recycling catalytic activity for an esterification reaction compared with sulfated zirconia without alumina doping and Al-doped sulfated zirconia without hierarchically porous structure.

关键词： one-pot synthesis doping Al-promoted sulfated zirconia hierarchical porous structure material science self-assembly

Development and Application of a Power Law Constitutive Model for Eddy Current Dampers

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2403-2419页

作者： Longteng Liang Zhouquan Feng Hongyi Zhang zhengqing chen Changzhao Qian School of Civil Engineering and Architecture Xiamen University of TechnologyXiamen361024China Hunan Provincial Key Laboratory ofWind and Bridge Engineering Hunan UniversityChangsha410082China Fujian Provincial Key Laboratory ofWind Disaster and Engineering Xiamen University of TechnologyXiamen361024China State Key Laboratory of Bridge Engineering Safety and Resilience Hunan UniversityChangsha410082China

Eddy current dampers (ECDs) have emerged as highly desirable solutions for vibration control due to theirexceptional damping performance and durability. However, the existing constitutive models present challenges tothe widespread implementation of ECD technology, and there is limited availability of finite element analysis (FEA)software capable of accurately modeling the behavior of ECDs. This study addresses these issues by developing anewconstitutivemodel that is both easily understandable and user-friendly for FEAsoftware. By utilizing numericalresults obtained from electromagnetic FEA, a novel power law constitutive model is proposed to capture thenonlinear behavior of ECDs. The effectiveness of the power law constitutive model is validated throughmechanicalproperty tests and numerical seismic analysis. Furthermore, a detailed description of the application process ofthe power law constitutive model in ANSYS FEA software is provided. To facilitate the preliminary design ofECDs, an analytical derivation of energy dissipation and parameter optimization for ECDs under harmonicmotionis performed. The results demonstrate that the power law constitutive model serves as a viable alternative forconducting dynamic analysis using FEA and optimizing parameters for ECDs.

关键词： Eddy current damper constitutive model finite element analysis vibration control power law constitutive model

Calculation method on shape finding of self-anchored suspension bridge with spatial cables

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Frontiers of Structural and Civil Engineering 2009年第2期3卷 165-172页

作者： Yan HAN zhengqing chen Shidong LUO Shankui YANG School of Civil Engineering and Architecture Changsha University of Science&TechnologyChangsha 410004China Wind Engineering Research Center Hunan UniversityChangsha 410082China China Railway Siyuan Survey and Design Group Co. Ltd.Wuhan 430063China China Railway Eryuan Engineering Group Co. Ltd.Chengdu 610031China

Based on the spatial model,a reliable and accurate calculation method on the shape finding of self anchored suspension bridge with spatial cables was studiedin this *** the principle that the shape of the main cables between hangers is catenary,the iteration method of calculating the shapes of the spatial main cables under the load of hanger forces was *** reasonable position of the saddle was determined according to the shape and the theoretical joint point of the main *** shapes of the main cables at completed cable stage werecalculated based on the unchanging principle of the zero-stress lengths of the main *** using a numerical method combining with the finite element method,one self-anchored suspension bridge with spatial cables was *** zero-stress length of the main cables,the position of the saddle,and the pre-offsetting of the saddle of the self-anchored suspension bridge were *** reasonable shapes of the main cables at bridge completion stage and completed cable stage were *** results show that the shape-finding calculation method is effective and reliable.

关键词： bridge engineering self-anchored suspension bridges special cables shape-finding calculation method

Experimental study of aerodynamic interference effects on aerostatic coefficients of twin deck bridges

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Frontiers of Structural and Civil Engineering 2009年第3期3卷 292-298页

作者： Zhiwen LIU zhengqing chen Gao LIU Xinpeng SHAO Wind Engineering Research Center Hunan UniversityChangsha 410082China China Highway Planning and Design Institute Consutants INC.Beijing 100000China Shandong Provincial Communications Planning and Design Institute Jinan 250000China

The aerodynamic interference effects on aero-static coefficients of twin deck bridges with large span were investigated in detail by means of wind tunnel *** distances between the twin decks and wind attack angles were changed during the wind tunnel test to study the effects on aerodynamic interferences of aerostatic coefficients of twin *** research results have shown that the drag coefficients of the leeward deck are much smaller than that of a single leeward *** drag coefficients of a windward deck decrease slightly com-pared with that of a single *** lift and torque coefficients of windward and leeward decks are also affected slightly by the aerodynamic interference of twin *** the aerodynamic interference effects on lift and torque coefficients of twin decks can be neglected.

关键词： twin decks aerodynamic interference effects aerostatic coefficients wind tunnel test

Development and application of metallic dampers in bridge engineering: a review

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Journal of Traffic and Transportation Engineering(English Edition) 2024年

作者： Wenxi Wang Sheng chen Bei chen Guokun Liu Xugang Hua zhengqing chen National Key Laboratory of Bridge Safety and Resilience， Hunan University Key Laboratory for Bridge and Wind Engineering of Hunan Province， College of Civil Engineering， Hunan University Shock and Vibration Technology Research Center， College of Civil Engineering， Hunan University School of Architectural Engineering， Hunan Institute of Engineering

Bridges may suffer from large-amplitude vibrations due to strong winds， earthquakes， human-induced loads， and vehicle-induced dynamic loads. Metallic dampers employed the energy dissipation from the hysteretic behavior of metal materials are among the most effective methods to mitigate bridge vibrations. This paper reviews the development and application of metallic-yielding dampers for the vibration control of bridges. Various theoretical models for metallic damper analyses are reviewed. Different yielding mechanisms and manufacturing materials of metallic dampers are discussed. Finally， the recent progress and application of bridge engineering are summarized. It can be concluded that each section of the torsion-type metallic damper exhibits a uniform stress state and undergoes plastic deformation simultaneously. Therefore， the damper has a strong energy dissipation capacity. Additionally， self-centering metallic dampers can automatically recover to their initial position after suffering an earthquake. Combined metallic dampers can take advantage of different types of dampers， thereby enhancing damping performance. Finally， these dampers will significantly enhance the seismic performance and overall safety of bridge structures. Future research will likely focus on hybrid systems that combine metallic dampers with other energy consumption mechanisms to further improve adaptability and energy dissipation， advancing the resilience and safety of bridge structures.

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泉州中芸洲海景花园建筑群体的干扰效应研究

建筑结构学报 2008年第2期29卷 19-24页

作者：李寿英陈政清湖南大学风工程试验研究中心湖南长沙410082

制作了缩尺比为1∶200的泉州中芸洲海景花园9栋高层建筑的刚性模型,在其外表面布置足够的测点进行了同步测压风洞试验。试验得到了该9栋高层建筑表面的平均风压系数和脉动风压系数。利用风洞试验得到的风荷载数据,研究了该9栋建筑的风... 详细信息

制作了缩尺比为1∶200的泉州中芸洲海景花园9栋高层建筑的刚性模型,在其外表面布置足够的测点进行了同步测压风洞试验。试验得到了该9栋高层建筑表面的平均风压系数和脉动风压系数。利用风洞试验得到的风荷载数据,研究了该9栋建筑的风致响应,包括位移和加速度响应。结果表明:左右或下游建筑的影响可能会增大上游建筑的背风面"吸力";泉州中芸洲海景花园9栋高层建筑相互干扰效应主要表现为"遮挡"效应,其顶部加速度响应均小于规范限值,能满足人体舒适度的相关要求。

关键词：高层建筑风致干扰风压系数位移加速度

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Wavelet-Based Nonstationary Wind Speed Model in Dongting Lake Cable-Stayed Bridge

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Engineering（科研） 2010年第11期2卷 895-903页

作者： Xuhui He Jun Fang Andrew Scanlon zhengqing chen School of Civil Engineering Central South University Department of Civil and Environmental Engineering The Pennsylvania State University

The wind-rain induced vibration phenomena in the Dongting Lake Bridge (DLB) can be observed every year, and the field measurements of wind speed data of the bridge are usually nonstationary. Nonstationary wind speed can be decomposed into a deterministic time-varying mean wind speed and a zero-mean stationary fluctuating wind speed component. By using wavelet transform (WT), the time-varying mean wind speed is extracted and a nonstationary wind speed model is proposed in this paper. The wind characteristics of turbulence intensity, integral scale and probability distribution of the bridge are calculated from the typical wind samples recorded by the two anemometers installed on the DLB using the proposed nonstationary wind speed model based on WT. The calculated results are compared with those calculated by the empirical mode decomposition (EMD) and traditional approaches. The compared results indicate that the wavelet-based nonstationary wind speed model is more reasonable and appropriate than the EMD-based nonstationary and traditional stationary models for characterizing wind speed in analysis of wind-rain-induced vibration of cables.

关键词： Time-Varying Mean Wind Speed Nonstationary Wind Speed Model Cable-Stayed Bridge Wavelet Transform (WT) Wind Characteristic Wind-Rain-Induced Vibration