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通讯作者:

韩艳,E-mail:ce_hanyan@163.com

中图分类号:U441+.3

文献标识码:A

文章编号:1672-6553-2023-21(4)-007-008

DOI:10.6052/1672-6553-2023-038

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参考文献 23
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参考文献 28
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目录contents

    摘要

    阻尼减振是拉索振动控制的主要措施,目前拉索-阻尼器系统的主要分析方法为复模态法.虽然采用复模态法可以精确分析拉索-阻尼器系统的阻尼比和频率等主要特征参数,但采用复模态法求出的拉索复振型由于不包含减振所需要的参数而被研究较少,而系统的振型对研究阻尼器的减振效果又具有非常重要的意义.文中首先采用复模态法求解了拉索-阻尼器系统,基于复振型的物理意义,引入相位函数,提出了一种改进的实数分离变量法,分析了阻尼力在拉索中的传递特征;建立了拉索-阻尼器系统的改进实模态分析方法,采用该方法求解得到的非线性运动方程通解与复模态法一致.基于该新方法计算得到的实模态振型,分析了阻尼器对拉索实际振型以及相位的影响.

    Abstract

    Damper are the main measure for cable vibration control, and complex modal analysis is the main approach of cable-damper system analysis. The complex frequencies derived from complex modal analysis allow an accurate analysis of system’s damping ratio and frequency, which is of major interest of bridge researchers. There is few studies for investigating the complex mode shape of cable since it does not contain the key parameters for vibration suppression. This paper focuses on the analysis of cable’s phase contained in the complex modal shape. Firstly, the complex modal analysis is used to analysis the cable-damper system, and the physical meaning of complex mode shape is explained. Subsequently, based on its physical meanings, the real separating variable method is improved by adding phase function, thus it is possible to explain how the damping force is translated in the cable. In this process, a set of nonlinear equations are obtained and their general solutions are solved, and the results obtained are consistent with those by the complex modal analysis. Finally, the effect of the damper on the cable’s real modal shape and phase is analyzed based on the results obtained.

  • 引言

  • 作为斜拉桥的关键承重构件,大跨度斜拉索极易在环境荷载下诱发大幅振动[1-3],如不加以抑制,则会导致拉索锚固端疲劳甚至破坏.目前拉索控制振动的主要方法有气动措施、结构措施以及阻尼耗能措施[4-6],其中安装阻尼器的耗能减振方法对不同机理和模态的振动均有抑制效果,因此应用较广.阻尼减振技术在拉索上应用至今,目前已有许多阻尼器设计方法,最早的拉索阻尼器设计方式可追溯至Kovacs[7],但该方法只能考虑一阶模态的最优值.Pacheco等[8]采用Galerkin方法分析了张紧弦模型,得到了安装有阻尼器的拉索模态阻尼比,并对阻尼参数无量纲化后得出了拉索各模态通用的阻尼器设计曲线.Pacheco的设计曲线方便易用,但由于Galerkin法不能考虑阻尼器对拉索模态的影响,并且忽略了垂度、拉索抗弯刚度等因素,因此计算结果偏大,有试验证明实测拉索最大阻尼比只达到了理论上限的60% [9].

  • 拉索-阻尼器系统具有较强的非比例阻尼特性,这是由阻尼器安装的不均匀性引起的.复模态理论[10]可以精确分析非比例阻尼系统,Krenk[11]在拉索-阻尼器系统中引入该理论,假设拉索振型为复模态振型,并认为复模态振型在阻尼器安装位置处不连续,以此提出了拉索-阻尼器系统的复模态分析方法,并在后续考虑了拉索垂度影响[12].Main和Jones[13-15]根据复模态方法,重点研究了阻尼器对拉索结构模态频率的影响,发现相比于线性阻尼,非线性阻尼器可以在更大的模态范围内实现最优的阻尼性能.Krenk和Høgsberg[16]采用复模态法分析了阻尼器并联刚度和集中质量的影响,发现集中质量对阻尼器的效果有增强作用,即“负刚度增强效应”.

  • 近年来,一些被动负刚度装置以及惯性装置陆续出现[17-18],为了分析这些装置对拉索阻尼器的增强效应,复模态法被广泛采用.Sun等[19]应用复模态理论研究了两根拉索之间连接调谐惯质阻尼器后的振动特性.Wang等[20]基于复模态方法从理论上研究了惯性质量对垂度拉索阻尼器效果的增强效应,并设置了模型试验进行验证.Shi 等[21]用复模态法分析了调谐惯质阻尼器对拉索的减振效果.孙浚杰等[22]采用复模态方法理论研究了惯性质量对拉索线性黏滞阻尼器减振效果的增强效应.刘菁等[23]使用复模态分析,对某实际拉索进行了惯质阻尼器参数设计,并分析了减振效果.程志鹏等[24]基于能量等效线性化方法和复模态法,分析了负刚度非线性黏滞阻尼器对斜拉索减振的增强效应.Xu等[25]采用磁流变阻尼器与可编程的智能控制装置实现了伪被动负刚度,并在斜拉索的理论分析中,使用复模态考察了阻尼系数和负刚度系数对斜拉索振动主动控制效果的影响.

  • 除此以外,若要精确考虑集中刚度、阻尼等因素对拉索模态的影响,也需要用到复模态.Nam Hoang等[26]应用复模态分析了弯曲刚度对拉索阻尼器的影响; Javaid Ahmad等[6]建立了双索之间连接连杆件的双索网络模型,采用复模态理论分析了拉索长度比、连杆的位置、拉索频率比和拉索质量-张力比对双索网络模型的振动特性影响; 杨超等[27]现场观测了超长拉索的高阶模态振动现象,随后根据复模态法研究了适用于拉索多模态振动的阻尼器参数方案.孙利民等[28]采用复模态法分析了垂度拉索在安装双阻尼器后的效果,并在实桥现场试验验证了理论计算精确性.Younespour等[29]采用复模态方法分析了垂度拉索在安装了横向弹性支承后的振型与频率变化,讨论了支撑刚度、支撑位置以及拉索的弯曲刚度等参数的影响.

  • 对于安装了阻尼器的拉索,桥梁研究者更关注拉索的阻尼比以及振动频率,多采用复模态法分析复频率,没有过多深入研究复模态振型,但其对研究阻尼器的减振效果又不容忽视.采用常规复模态法得到的复振型可以表示拉索的振幅与相位,并且其中相位与拉索各点的运动衰减息息相关,但由于是复数分析,其物理含义不直观,所以没有办法研究阻尼器对振型的影响.本文基于复振型与分离变量法提出了改进实模态分析方法,该方法可以清晰地描述拉索-阻尼器系统运动衰减与相位的相关性,也能自洽地解释阻尼器对拉索的振型影响.本文主要结构如下:第一部分为拉索-阻尼器系统的常规分析方法; 第二部分为改进的实模态分析方法与求解; 第三部分为阻尼器对拉索振型与相位影响的实例分析; 最后在第四部分对全文进行了总结.

  • 1 拉索-阻尼器系统的常规分析方法

  • 1.1 实数分离变量法

  • 本文采用均匀张紧弦模型表示拉索,忽略拉索本身的阻尼以及重力影响,如图1所示,引入函数表示集中力,则拉索自由运动微分方程可写为:

  • ρ2u(x,t)t2+cul1,ttδx-l1=T2u(x,t)x2
    (1)
  • 式中ρ为拉索的每延米质量,T为拉索索力,L为拉索长度,l1为阻尼器的安装位置,uxt)表示t时刻x位置处斜拉索的振动位移,c为阻尼器的阻尼黏性系数,δ为狄拉克函数.

  • 图1 张紧弦-阻尼器模型

  • Fig.1 Taut cable with external viscous damper

  • 除去阻尼器安装点和两端点以外,拉索不再受外力,因此可将拉索按两端点和阻尼安装点分为两段,这两段拉索必定满足无外加激励下弦振动方程:

  • ρ2u(x,t)t2-T2u(x,t)x2=0
    (2)
  • 对方程(2)的解作分离变量法假设uxt)=YxFt),并且考虑实际物理意义,认为Yx),Ft)都为实数,代入方程(2)得到:

  • ρd2F(t)dt2+KF(t)=0
    (3)
  • 式中K=-Td2Yxdx2/Yx,式(3)可视为无阻尼振子的自由运动方程,其求得的时间函数必然不会随时间衰减,这与实际事实相违背,因此传统的实数分离变量法不再适用于拉索-阻尼器系统求解.问题也由此提出:拉索-阻尼器系统的位移应当如何假设与求解?并且引申出以下问题:拉索上安装的阻尼器怎样影响其他无外力作用的点自由衰减?即阻尼器产生的阻尼力如何在拉索中传递.

  • 1.2 复模态法

  • 有关拉索-阻尼器系统的精确求解,Krenk早在文献[11]给出了解答,后续许多拉索系统研究都是基于此方法.下面应用复模态法对拉索-阻尼器系统进行分析,由上一部分可知,拉索运动无法分离成实数空间函数与实数时间函数乘积的形式,既然如此,不妨假设它们均为复数,即:

  • u~(x,t)=Y~(x)eiω~t
    (4)
  • 式中ω~=|ω~|1-ξ2+ξi为复频率,Y~x为复振型,ξ为系统阻尼比.将式(4)代入式(2)得到:

  • d2Y~(x)dx2+β~2Y~(x)=0
    (5)
  • 式中β~=ρ/Tω~为复波数,方程通解为:

  • Y~(x)=A~1sinβ~x+A~2cosβ~x
    (6)
  • A~1A~2为待定系数,需要根据边界条件确定,阻尼器安装点由于阻尼力的存在,拉索复振型导数并不连续,因此需要分为两段,如图2所示,右下标为1代表左边索段,为2代表右边索段.假索的振动幅度较小,则索轴线与水平轴的夹角为u/x,因此得到这两段索的边界条件与阻尼器安装点的平衡条件:

  • u1(0,t)=0u2(0,t)=0u1l1,t=u2l2,tTu1l1,tx+u2l2,tx+cul1,tt=0
    (7)
  • 复振型求得:

  • Y~(x)=Y~0sinβ~x1sinβ~l10x1<l1Y~0sinβ~x2sinβ~l20x2<l2
    (8)
  • 图2 拉索分段与安装点受力平衡

  • Fig.2 Balance of forces at mounting points

  • 式中Y~0为阻尼器安装点的位移复幅值,需要根据拉索自由振动的初始状态求解,再将式(8)代入,安装点的平衡条件得到:

  • cotβ~l1L+cotβ~l2L+icTm=0
    (9)
  • 超越方程(9)称为波数方程,根据方程(9)可以求解出复波数β~,从而实现复模态方法的闭合分析.桥梁研究者主要关心拉索的阻尼比以及振动频率,因此只需要求解方程(9)就可以分析出阻尼器对拉索的阻尼比和频率影响.但由于复数的物理意义并不明确,对于阻尼器产生的阻尼力如何在拉索中传递这一点,只分析波数方程无法给出清晰的解释.

  • 2 改进实模态求解方法

  • 2.1 基于改进实数分离变量法的系统建模

  • 由上一部分内容可知,复模态解u~xt能够满足方程(2)及其边界条件,那么其实部与虚部也会满足要求,我们对式(4)作稍许变化:

  • u~(x,t)=Y~(x)eiω~t=|Y~(x)|eiarg(x)ieiω~t=|Y~(x)|e-ξ|ω~|tei[ωt+arg(x)]
    (10)
  • 式中|·|为取模运算,arg(x)为复振型Y~x的辐角,ω=|ω~|1-ξ2为自由振动频率.应用欧拉公式,可以发现式(10)的实部或者虚部就是随着时间变化振幅指数衰减的谐波,除了各点的运动幅值不同外,各点的运动相位也不同.模为拉索实际振幅,辐角为拉索各点的运动相位[30].由复振型的物理意义,我们对实数分离变量法进行改进,在时间函数内添加一个空间相关的相位函数φx):

  • u(x,t)=Y(x)F(t+φ(x))
    (11)
  • 此时式(11)也一定能够适用于拉索-阻尼器系统求解,令τ=t+φx),注意:

  • 2u(x,t)t2=Y(x)d2F(τ)dτ2
    (12a)
  • 2ux2=d2Y(x)dx2F(τ)+2dY(x)dxdF(τ)dτdφ(x)dx+Y(x)d2F(τ)dτ2dφ(x)dx2+dF(τ)dτd2φ(x)dx2
    (12b)
  • 代入方程(2)并整理得到:

  • M-d2F(τ)dτ2+C-dF(τ)dτ+K-F(τ)=0
    (13a)
  • M-=ρ-Tdφ(x)dx2C-=-T2dY(x)dxdφ(x)dx/Y(x)+d2φ(x)dx2K-=-Td2Y(x)dx2/Y
    (13b)
  • 由方程(13)可以发现,对于系统上无外力段的任意一点x,都可视为有阻尼振子,为振子的广义位移,当然其前提条件是dφx)/dx≠0,即φx)≠常数,若令dφx)/dx=0,则方程(13)退化为式(3).

  • 图3 拉索微元及等效模型

  • Fig.3 Differential unit of cable and its equivalent model

  • 提取某x0处拉索微元如图3所示,对于拉索上任一不受外力的微元,其上索力横向不平衡量与惯性力相等,如果微元两端无相位差(dφx)/dx=0),索力横向不平衡量只提供刚度回复力,可等效为无阻尼振子(图3(b)); 如果存在相位差(dφx)/dx≠0),索力横向不平衡量不仅提供刚度恢复力,还提供阻尼力与惯性力,等效模型如图3(c).由此可见相位差dφx)/dx在阻尼器阻尼力传递中扮演着重要的角色,并且会对微元的惯性力和刚度回复力产生影响,间接导致微元振动幅值的变化,从而影响拉索振型.

  • 2.2 基于改进实数分离变量法的实模态求解方法

  • 根据复模态法,拉索-阻尼器系统的自由振动为:各点阻尼比、频率一致、相位差不同的周期衰减谐波,因此将方程(13)中的Fτ)设为:

  • F(τg)=e-ζτsin(ωτ)
    (14)
  • 为了后续书写方便,用对数减幅ζ表示衰减,ω仍然为自由振动圆频率.将其代入式(13)并考虑三角函数的系数为0,得到如下方程组:

  • Y''+ζ2+ω2β2Y=φ'22φ'Y'=-φ''+2ζφ'2-1β2Y
    (15)
  • 式中′,″分别表示对x求一阶导数和二阶导数,β=T/ρ.令Yx=yxeζφx,可使方程变为:

  • y''+ω2-ζ2β2y=ω2φ'2y
    (16a)
  • 2φ'y'+φ''+2ζβ2y=0
    (16b)
  • 式中yx)即为实际的振幅,式(16)是一组非线性的常微分方程,若要求其通解,需要做一些变化,令φ'=fxgx,那么φ''=f'xgx-g'xgxφ',观察式(16b),发现若:

  • f'(x)g(x)=-2ζβ2
    (17a)
  • 式(16b)则变为:

  • g'(x)g(x)=2y'y
    (17b)
  • 因此可得到:gx=y2xfx=-2ζβ2y2xdx,令Γx=y2xdx,可以推出φ′(x)以及yx)与Γx)关系:

  • φ'(x)=-2ζβ2Γ(x)Γ'(x)Γ'(x)=y2Γ''(x)=2yy'Γ'''(x)=2yy''+2y'2
    (18)
  • 再将式(16a)变化为关于Γx)的非线性常微分方程:

  • 2Γ'Γ'''-Γ''2+4ω2-ζ2β2Γ'2-16ω2ζ2β4Γ2=0
    (19)
  • 方程(19)不难求出特解,只需要令Γx)=esx,可得特征方程:

  • s2-2ζβ2s2+2ωβ2=0
    (20)
  • Γx)的四个特解,即:

  • Γ1(x)=e2ξxβ,Γ2(x)=e-2ζxβ,Γ3(x)=ei2ωxβ,Γ4(x)=e-i2ωxβ
    (21)
  • 一般来说,非线性方程通解无法表示为特解的组合叠加,但这四个特解存在一种特殊的组合使其能够表达方程(19)的通解,将其变化为三角函数和双曲函数并整理得到如下通解:

  • Γ(x)=Aβ2ωcos2ωxβ+Bβ2ωsin2ωxβ+Dβ2ζsinh2ζxβ
    (22)
  • 式中sinh以及下文的cosh、tanh分别为双曲正弦、双曲余弦和双曲正切函数; ABD为待确定实常数,并且必须满足A2+B2=D2,具体的取值需要根据边界条件和某一点初始振幅确定.实振型函数yx)与相位差dφxdxΓx)表示:

  • y(x)=Γ'(x),dφ(x)dx=-2ζβ2Γ(x)Γ'(x)
    (23)
  • dφxdxΓx)的原函数得到相位函数φx):

  • φ(x)=1ωarctantanωxβ+12arctanABtanhζxβ+nπω+C
    (24)
  • 式中C为待定常数,需要根据某一点初始相位确定,n=0,1,2,···保证函数连续.拉索各点的位移因此表示为:

  • u(x,t)=y(x)e-ζtsin(ωt+ωφ(x))
    (25)
  • 式(25)中有ABCD四个待定参数,两段不受外力的拉索都可用此结果表示,因此有8个待定系数以及两个假设的系统参数ζω,一共10个未知量,在已知边界条件(26a)、平衡条件(26b)、阻尼器安装点初始状态(26c)和系数关系(26d)的情况下,可得到如下10个方程:

  • y1(0)=0,y2(0)=0y1l1=y2L-l1ωφ1l1=ωφ2L-l1
    (26a)
  • dy1l1dx+dy2L-l1dx=cζTy1l1dφ1l1dx+dφ2L-l1dx+cT=0
    (26b)
  • y1l1=y0,ωφ1l1=φ0
    (26c)
  • A12+B12=D12,A22+B22=D22
    (26d)
  • 式中下标为1表示阻尼器左边段拉索,下标为2表示阻尼器右边段拉索,Y0为阻尼器安装点的初始幅值,φ0为阻尼器安装点的初始相位.通过式(26)中包含的10个方程,最终可以得出8个待定系数的解析值,以及两个超越方程:

  • sin2ωx1βLcosh2ζx2βL+sin2ωx2βLcosh2ζx1βL=sin2ωβ
    (27a)
  • sinh2ωx1βLcos2ζx2βL+sinh2ωx2βLcos2ζx1βL+sinh2ζβcosh2ζβ-cos2ωβ=cTρ
    (27b)
  • 系统参数ζω的确定则需要根据该超越方程组求解,这两个超越方程其实就是复波数方程(9)的实部与虚部,与Main在文献[13]中求得的结果一致,方程(27a)表达了ζωβ之间的关系,Main在文中称之为“相位方程”,方程(27b)则表现了阻尼器对系统的影响.

  • 3 实例分析

  • 由式(26b)可知,拉索的振幅函数与相位函数在阻尼器安装点处不可导,整根拉索被分为了两段,并且两段的边界相似,均为一端固定一端阻尼约束.因此为了方便分析,作如图4所示的理想模型考虑,选取阻尼器安装点的左半边索段L′,并在索段右边提供一个不变的索力使结构受力平衡,索力方向始终与索右端截面垂直.

  • 图4 拉索-阻尼器半边模型

  • Fig.4 Half-sided model of the cable-damper system

  • 取拉索左端固定点位置的相位φ(0)=0,根据边界条件求出振幅与相位函数表达式,并对振幅函数最大值归一,得到正则振幅函数y-x-与正则相位函数φ-x-:

  • y-(x-)=Ncosh2ζ'x--cos2ω'x-φ-(x-)=ωφ(x-)π=arctantanω'-x-tanhζ'-xπ+2n+12
    (28)
  • 式中x-=x/l'N[·]为最大值归一算子,n=0,1,2,···用于保证φ-x-连续,无量纲阻尼ζ′与无量纲频率ω′根据方程(27)取值如下:

  • 小阻尼情况(c2):

  • ω'=ωβ=kπ2(k=1,3,5,)ζ'=ζβ=arccoshc2+TρTρ-c2
    (29a)
  • 大阻尼情况(c2):

  • ω'=ωβ=kπ2(k=2,4,6,)ζ'=ζβ=arccoshc2+Tρc2-Tρ
    (29b)
  • 其中ω′只能取π/2的整数倍,并且奇数倍只能在小阻尼(c2)的情况下选取,此时拉索为对称模态; 偶数倍则为大阻尼(c2)的情况下选取,拉索为反对称模态.

  • 由式(28)可知y-x-φ-x-只与ζ′、ω′有关,这里我们只关心阻尼器为拉索附加阻尼对拉索振幅与相位的影响,假设可以通过调节Tρc使ζ′任意变化,图5、图6分别作出了ζ′=0和ζ′=0.1时y-x-φ-x-dφ-x-/dx-的函数图像; ζ′=0表示阻尼器对拉索不产生影响,ζ′=0.1表示阻尼器赋予拉索阻尼并使拉索运动衰减.

  • 图5 无附加阻尼时拉索振幅、相位曲线

  • Fig.5 Amplitude and phase curve of the cable without additional damping

  • 由图5、图6可以看出,阻尼器为拉索结构附加的阻尼会影响拉索运动的振型与相位.在阻尼器附加阻尼为0的情况下,拉索微元两端的相位差dφx)/dx都为0,但是在驻点处相位突变了π,因此运动方向突变为反向,相位差在驻点处为无穷大,这与经典的拉索模态分析结果一致.但在阻尼器附加阻尼不为0的情况下,拉索不再存在不动的驻点,相位也不是发生突变,而是有一个连续的变化过程,拉索总体表现为行波与驻波的叠加.

  • 图6 附加阻尼时拉索振幅、相位曲线

  • Fig.6 Amplitude and phase curve of the cable with additional damping

  • 4 总结

  • 本文对拉索-阻尼器系统进行了研究,首先采用复模态法也即复数分离变量法求解了该系统; 随后依据复振型的物理意义对实数分离变量法进行了改进,得出了阻尼器通过相位差传递阻尼力的结论,并得到了一组有关拉索-阻尼器系统实际振幅和相位函数的非线性方程组; 最后求解了该方程组,补充了复模态法对应的实模态求解方法,并简要分析了阻尼器对拉索振型与相位的影响.通过以上分析,本文得出了如下结论:

  • (1)复振型的模为拉索实际振幅,辐角为拉索各点的运动相位.

  • (2)在拉索阻尼器系统中,拉索通过相位差传递阻尼器产生的阻尼力,并且相位差还会对拉索的振型造成影响.

  • (3)对于无阻尼拉索,其2阶以上的振型存在驻点,相位在驻点处突变了π,相位差在该点为无穷大.

  • (4)而安装了集中阻尼器的拉索,阻尼器为拉索结构附加了非对称阻尼,导致拉索不存在静止的驻点,相位在原驻点处也不发生突变,而是有一个连续的变化过程,表现出了行波与驻波叠加的特性.

  • 本文从拉索相位的角度分析了阻尼器对拉索产生的影响,该方法能够解释阻尼力的传递并描述阻尼器对振型的影响,可以为拉索的阻尼器设计提供参考.

  • 参考文献

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  • 参考文献

    • [1] NI Y Q,WANG X Y,CHEN Z Q,et al.Field observations of rain-wind-induced cable vibration in cable-stayed Dongting Lake Bridge [J].Journal of Wind Engineering and Industrial Aerodynamics.2007,95:303-328.

    • [2] JING H Q,HUANG F Y,HE X H,et al.Wake-induced vibrations of tandem flexible cable models in a wind tunnel [J].Ocean Engineering,2021,233.

    • [3] LIU Z W,LI S Q,WANG L H,et al.Experimental investigation on high-mode vortex-induced vibration of a flexible stay cable in smooth flow [J].Journal of Bridge Engineering.2022,27(8):04022068.

    • [4] CHEN Z Q,WANG X Y,KO J M,et al.MR damping system for mitigating wind-rain induced vibration on Dongting Lake cable-stayed bridge [J].Wind and Structures,2004,7:293-304.

    • [5] KLEISSL K.Cable aerodynamic control:wind tunnel studies[D].Copenhagen:Technical University of Denmark,2013.

    • [6] AHMAD J,CHENG S H.Effect of cross-link stiffness on the in-plane free vibration behaviour of a two-cable network [J].Engineering Structures,2013,52:570-580.

    • [7] KOVACS I.Zur Frage der Seilschwingungen und der seildämpfung [J].Bautechnik,1982,59(10):325-332.

    • [8] PACHECO B M,FUJINO Y,SULEKH A.Estimation curve for modal damping in stay cable with viscous damper [J].Journal of Structural Engineering,1993,119(6):1961-1979.

    • [9] ZHOU H,SUN L,XING F.Damping of full-scale stay cable with viscous damper:experiment and analysis [J].Advances in Structural Engineering,2014;17(2):265-274.

    • [10] FOSS K A.Coordinates which uncouple the equation of damped linear dynamic system [J].Journal of Applied Mechanics-ASME,1958,25,(1):361-364.

    • [11] KRENK S.Vibration of a taut cable with an external damper [J].Journal of Applies Mechanics,2000,67(4):772-776

    • [12] KRENK S,NIELSEN S.Vibration of a shallow cable with a viscous damper [C].Proceeding of the Royal Society of London Series A:Mathematical Physical and Engineering Sciences,2002,458:339-357.

    • [13] MAIN J A,JONES N P.Free vibrations of taut cable with attached damper Ⅰ:linear viscous damper [J].Journal of Engineering Mechanics,2002,128(10):1062-1071.

    • [14] MAIN J A,JONES N P.Free vibration of taut cable with attaches damper Ⅱ:nonlinear damper [J].Journal of Engineering Mechanics,2002,128(10):1072-1081.

    • [15] MAIN J A,JONES N P.Evaluation of viscous dampers for stay cable vibration mitigation [J].Journal of Bridge Engineering,2001,6(6):385-388.

    • [16] KRENK S,HØGSBERG J R.Damping of cables by a transverse force [J].Journal of Engineering Mechanics,2005,131(4):340-348.

    • [17] SMITH M C.Synthesis of mechanical networks:the inerter [J].IEEE Transactions on Automatic Control,2002,47(10):1648-1662.

    • [18] SHI X,ZHU S.Magnetic negative stiffness dampers [J].Smart Materials and Structures,2015,24(7):072002.

    • [19] SUN L M,HONG D X,CHEN L.Cables interconnected with tuned inerter damper for vibration mitigation [J].Engineering Structures,2017,151:57-67.

    • [20] WANG Z H,GAO H,XU Y W,et al,Impact of cable sag on the efficiency of an inertial mass damper in controlling stay cable vibrations [J].Smart Struct and System,2019,24(1):83-94.

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