车辆荷载作用下简支梁桥动力特性分析及模态参数识别
|
摘要
为研究车辆荷载作用对简支梁桥结构动力性能的影响,对车辆荷载作用下的简支梁桥进行能量分析并采用随机子空间法(SSI)和RDT-STD法对简支梁桥进行模态参数识别研究。分析不同车速激励下的桥梁能量分布情况,对比不同模态参数识别方法的频率、阻尼和振型的识别结果。结果表明:随着车速的增加,简支梁桥的加速度幅值不断增大,能量向高频段偏移,更容易激发结构的高阶模态;随机子空间法(SSI)和RDT-STD法均能有效识别出简支梁桥的竖向频率,SSI法对于简支梁桥频率和阻尼的识别精度高于RDTSTD法,但两种识别方法对阻尼的识别相对误差较大,且存在一定的离散性。
To study the effect of dynamic performance of vehicle load on simply supported beam bridge structure,in the paper,the energy analysis of a simply supported beam bridge under vehicle load was carried out. The modal parameters identification of simply supported beam bridge was carried out with the stochastic subspace identification method( SSI) and the RDT-STD method.The energy distribution of bridge under different driving speeds was analyzed.The frequency,damping and vibration modal recognition results of different modal parameter identification methods were compared.The results showed that,as the vehicle speed increased,the amplitude of the acceleration response of the simply supported beam bridge increased continuously,and the energy shifted to the high frequency band,which made it easier to excite the higher-order mode of the structure. The SSI method and the RDT-STD method could identify the vertical frequency of the simply supported beam bridge effectively. The frequency and damping identification accuracy of SSI method was higher than that of RDT-STD,but the two identification methods had large relative errors in the identification of damping,and there was a certain discreteness.
To study the effect of dynamic performance of vehicle load on simply supported beam bridge structure,in the paper,the energy analysis of a simply supported beam bridge under vehicle load was carried out. The modal parameters identification of simply supported beam bridge was carried out with the stochastic subspace identification method( SSI) and the RDT-STD method.The energy distribution of bridge under different driving speeds was analyzed.The frequency,damping and vibration modal recognition results of different modal parameter identification methods were compared.The results showed that,as the vehicle speed increased,the amplitude of the acceleration response of the simply supported beam bridge increased continuously,and the energy shifted to the high frequency band,which made it easier to excite the higher-order mode of the structure. The SSI method and the RDT-STD method could identify the vertical frequency of the simply supported beam bridge effectively. The frequency and damping identification accuracy of SSI method was higher than that of RDT-STD,but the two identification methods had large relative errors in the identification of damping,and there was a certain discreteness.
引文
[1]胡立华.车辆移动作用下大跨度连续梁桥动力响应分析[D].长沙:中南大学,2014.
[2]谢旭,吴冬雁,王建峰,等.伸缩缝车辆冲击引起的钢箱梁桥振动特性[J].浙江大学学报(工学版),2009,43(10):1923-1930.
[3] CHIANG D Y,LIN C S. Identification of Modal Parameters from Nonstationary Ambient Vibration Data Using the ChannelExpansion Technique[J]. Journal of Mechanical Science and Technology,2011,25(5):1307-1315.
[4] SHI W X,SHAN J Z,LU X L. Modal Identification of Shanghai World Financial Center Both from Free and Ambient Vibration Response[J]. Engineering Structures,2012,36:14-26.
[5] DE VIVO A, BRUTTI C, LEOFANTI J L. Modal Shape Identification of Large Structure Exposed to Wind Excitation by Operational Modal Analysis Technique[J]. Mechanical Systems and Signal Processing,2013,39:195-206.
[6] EMIN A M,AHMET D. Modal Identification of Different RC Frames Using Experimental Measurements[J]. Journal of Testing and Evaluation,2013,41(6):970-976.
[7] TONDREAU G, DERAEMAEKER A. Numerical and Experimental Analysis of Uncertainty on Modal Parameters Estimated with the Stochastic Subspace Method[J]. Journal of Sound and Vibration,2014,333(18):4376-4401.
[8] HEVER M, JOHANNIO M, PETER T. Identification and Monitoring of Modal Parameters in Aircraft Structures Using the Natural Excitation Technique(NExT)Combined with the Eigensystem Realization Algorithm(ERA)[J]. Journal of Aerospace Engineering,2010,23(2):99-104.
[9] HUANG Z,GU M. Envelope Random Decrement Technique for Identification of Nonlinear Damping of Tall Buildings[J]. Journal of Structural Engineering,2016:04016101.
[10] VELAZQUE A,SWARTZ R A. Output-Only Cycle-Stationary Linear-Parameter Time-Varying Stochastic Subspace Identification Method for Rotating Machinery and Spinning Structures[J].Journal of Sound and Vibration,2014,337:45-70.
[11] KIM C W, KAWATANI M, HAO. J. Modal Parameter Identification of Short Span Bridges Under a Moving Vehicle by Means of Multivariate AR Model[J]. Structure and Infrastructure Engineering,2012,8(5):459-472.
[12]秦世强,蒲黔辉,施洲.环境激励下大型桥梁模态参数识别的一种方法[J].振动与冲击,2012(2):95-100.
[2]谢旭,吴冬雁,王建峰,等.伸缩缝车辆冲击引起的钢箱梁桥振动特性[J].浙江大学学报(工学版),2009,43(10):1923-1930.
[3] CHIANG D Y,LIN C S. Identification of Modal Parameters from Nonstationary Ambient Vibration Data Using the ChannelExpansion Technique[J]. Journal of Mechanical Science and Technology,2011,25(5):1307-1315.
[4] SHI W X,SHAN J Z,LU X L. Modal Identification of Shanghai World Financial Center Both from Free and Ambient Vibration Response[J]. Engineering Structures,2012,36:14-26.
[5] DE VIVO A, BRUTTI C, LEOFANTI J L. Modal Shape Identification of Large Structure Exposed to Wind Excitation by Operational Modal Analysis Technique[J]. Mechanical Systems and Signal Processing,2013,39:195-206.
[6] EMIN A M,AHMET D. Modal Identification of Different RC Frames Using Experimental Measurements[J]. Journal of Testing and Evaluation,2013,41(6):970-976.
[7] TONDREAU G, DERAEMAEKER A. Numerical and Experimental Analysis of Uncertainty on Modal Parameters Estimated with the Stochastic Subspace Method[J]. Journal of Sound and Vibration,2014,333(18):4376-4401.
[8] HEVER M, JOHANNIO M, PETER T. Identification and Monitoring of Modal Parameters in Aircraft Structures Using the Natural Excitation Technique(NExT)Combined with the Eigensystem Realization Algorithm(ERA)[J]. Journal of Aerospace Engineering,2010,23(2):99-104.
[9] HUANG Z,GU M. Envelope Random Decrement Technique for Identification of Nonlinear Damping of Tall Buildings[J]. Journal of Structural Engineering,2016:04016101.
[10] VELAZQUE A,SWARTZ R A. Output-Only Cycle-Stationary Linear-Parameter Time-Varying Stochastic Subspace Identification Method for Rotating Machinery and Spinning Structures[J].Journal of Sound and Vibration,2014,337:45-70.
[11] KIM C W, KAWATANI M, HAO. J. Modal Parameter Identification of Short Span Bridges Under a Moving Vehicle by Means of Multivariate AR Model[J]. Structure and Infrastructure Engineering,2012,8(5):459-472.
[12]秦世强,蒲黔辉,施洲.环境激励下大型桥梁模态参数识别的一种方法[J].振动与冲击,2012(2):95-100.