斜拉索索力识别精度的提高方法
|
摘要
针对基于环境激励的斜拉索实测信号由于环境干扰而呈现出非平稳性和非平滑性的问题,提出了利用五点三次平滑法对快速傅里叶变换(FFT)得到的频域数据进行平滑处理,即考虑多因素影响来提高斜拉索索力识别精度。以实际斜拉桥工程中的拉索实测信号为研究对象,应用五点三次平滑法对拉索信号进行平滑消噪处理,考虑采样时间和采样点数对拉索频率识别精度的影响,利用求极值方法确定拉索各阶频率值及其位置,比较了基频法、频差法和峰值法确定拉索索力的计算精度,进行了索力测试的误差分析。结果表明:五点三次平滑法结合极值处理可以很好地识别拉索各阶频率,各因素对拉索频率的识别精度影响也有所不同,为频率法更加准确识别斜拉索索力提供了方便;同时也为开发高精度的索力测试仪器提供了有效依据。
Based on the measured signal of stay cable under ambient excitation,the method with five points and three times was put forward to smoothly process the frequency-domain data obtained from fast Fourier transform(FFT) because of the non-stability and non-smoothness resulting from ambient interference.This method was used to enhance the identification precision for stay cable tension by considering some influencing factors.Using the measured signal of stay cable in practical engineering,the method with five points and three times was used to process smooth denoise.By considering the effect of sampling time and sampling numbers on the identification precision for stay cable tension,the method to calculate extreme method was used to determine the frequency and its location of stay cable at various ranks.The precisions of basic frequency method,frequency difference method and peak value method were compared.The error analysis for cable tension measurement was also carried out.The results show that combining with extreme process,the method with five points and three times can well identify the frequency of stay cable at various ranks;different factors have different influences on the identification precision for stay cable frequency.It is possible to identify the stay cable tension more accurately by basic frequency method,and it also provides the efficient proof for the development of cable tension measurement instrument with high precision.
Based on the measured signal of stay cable under ambient excitation,the method with five points and three times was put forward to smoothly process the frequency-domain data obtained from fast Fourier transform(FFT) because of the non-stability and non-smoothness resulting from ambient interference.This method was used to enhance the identification precision for stay cable tension by considering some influencing factors.Using the measured signal of stay cable in practical engineering,the method with five points and three times was used to process smooth denoise.By considering the effect of sampling time and sampling numbers on the identification precision for stay cable tension,the method to calculate extreme method was used to determine the frequency and its location of stay cable at various ranks.The precisions of basic frequency method,frequency difference method and peak value method were compared.The error analysis for cable tension measurement was also carried out.The results show that combining with extreme process,the method with five points and three times can well identify the frequency of stay cable at various ranks;different factors have different influences on the identification precision for stay cable frequency.It is possible to identify the stay cable tension more accurately by basic frequency method,and it also provides the efficient proof for the development of cable tension measurement instrument with high precision.
引文
[1]魏建东,刘山洪.基于拉索静态线形的索力测定[J].工程力学,2003,20(3):104-107.WEI Jian-dong,LIU Shan-hong.Tension Calculationof Cable by Its Static Profile[J].Engineering Mechan-ics,2003,20(3):104-107.
[2]苏成,徐郁峰,韩大建.频率法测量索力中的参数分析与索抗弯刚度的识别[J].公路交通科技,2005,22(5):75-78.SU Cheng,XU Yu-feng,HAN Da-jian.ParameterAnalysis and Identification of Bending Stiffness ofCables During Tension Measurements by FrequencyMethod[J].Journal of Highway and TransportationResearch and Development,2005,22(5):75-78.
[3]王济,胡晓.MATLAB在振动信号处理中的应用[M].北京:中国水利水电出版社,2006.WANG Ji,HU Xiao.Application of MATLAB in Vi-bration Signal Process[M].Beijing:China WaterPower Press,2006.
[4]许俊.斜拉索索力简化计算中的精度分析[J].同济大学学报,2001,29(5):611-615.XU Jun.Precision Analysis of Calculating TensionForce of Cable[J].Journal of Tongji University,2001,29(5):611-615.
[5]李东生.拱桥吊杆损伤监测与健康诊断[D].哈尔滨:哈尔滨工业大学,2007.LI Dong-sheng.Arch Bridge Suspender Damage Moni-toring and Health Diagnosis[D].Harbin:Harbin In-stitute of Technology,2007.
[6]周绪红,戴鹏,狄谨.钢箱梁斜拉桥成桥索力优化分析[J].建筑科学与工程学报,2007,24(2):19-23.ZHOU Xu-hong,DAI Peng,DI Jin.OptimizationAnalysis of Cable Tensions of Dead Load State forCable-stayed Bridge with Steel Box Girder[J].Journalof Architecture and Civil Engineering,2007,24(2):19-23.
[7]梁鹏,徐岳,刘永健.斜拉索分析统一理论及其应用[J].建筑科学与工程学报,2006,23(1):68-77.LIAN Peng,XU Yue,LIU Yong-jian.Unified Analy-sis Theory of Cable Stay and Its Applications[J].Journal of Architecture and Civil Engineering,2006,23(1):68-77.
[8]乔陶鹏,严普强,邓焱,等.斜拉索索力估算中振动信号处理方法的改进[J].清华大学学报:自然科学版,2003,43(5):644-647.QIAO Tao-peng,YAN Pu-qiang,DENG Yan,et al.Data Processing of Vibration Signals for Cable Ten-sion Estimation[J].Journal of Tsinghua University:Science and Technology,2003,43(5):644-647.
[9]魏建东.索力测定常用公式精度分析[J].公路交通科技,2004,21(2):53-56.WEI Jian-dong.Precision Analysis of ConventionalFormulas Calculating Cable Tension[J].Journal ofHighway and Transportation Research and Develop-ment,2004,21(2):53-56.
[10]程磊,瞿伟廉.基于Hilbert-Huang变换理论的非平稳数据处理[J].建筑科学与工程学报,2007,24(1):26-30.CHENG Lei,QU Wei-lian.Non-stationary Data Pro-cessing Based on Hilbert-Huang Transform Theory[J].Journal of Architecture and Civil Engineering,2007,24(1):26-30.
[11]陈刚,任伟新.基于环境振动的斜拉索基频识别[J].地震工程与工程振动,2003,23(3):100-106.CHEN Gang,REN Wei-xin.Ambient Vibration BasedIdentification of Fundamental Frequencies of StayCables[J].Earthquake Engineering and EngineeringVibration,2003,23(3):100-106.
[2]苏成,徐郁峰,韩大建.频率法测量索力中的参数分析与索抗弯刚度的识别[J].公路交通科技,2005,22(5):75-78.SU Cheng,XU Yu-feng,HAN Da-jian.ParameterAnalysis and Identification of Bending Stiffness ofCables During Tension Measurements by FrequencyMethod[J].Journal of Highway and TransportationResearch and Development,2005,22(5):75-78.
[3]王济,胡晓.MATLAB在振动信号处理中的应用[M].北京:中国水利水电出版社,2006.WANG Ji,HU Xiao.Application of MATLAB in Vi-bration Signal Process[M].Beijing:China WaterPower Press,2006.
[4]许俊.斜拉索索力简化计算中的精度分析[J].同济大学学报,2001,29(5):611-615.XU Jun.Precision Analysis of Calculating TensionForce of Cable[J].Journal of Tongji University,2001,29(5):611-615.
[5]李东生.拱桥吊杆损伤监测与健康诊断[D].哈尔滨:哈尔滨工业大学,2007.LI Dong-sheng.Arch Bridge Suspender Damage Moni-toring and Health Diagnosis[D].Harbin:Harbin In-stitute of Technology,2007.
[6]周绪红,戴鹏,狄谨.钢箱梁斜拉桥成桥索力优化分析[J].建筑科学与工程学报,2007,24(2):19-23.ZHOU Xu-hong,DAI Peng,DI Jin.OptimizationAnalysis of Cable Tensions of Dead Load State forCable-stayed Bridge with Steel Box Girder[J].Journalof Architecture and Civil Engineering,2007,24(2):19-23.
[7]梁鹏,徐岳,刘永健.斜拉索分析统一理论及其应用[J].建筑科学与工程学报,2006,23(1):68-77.LIAN Peng,XU Yue,LIU Yong-jian.Unified Analy-sis Theory of Cable Stay and Its Applications[J].Journal of Architecture and Civil Engineering,2006,23(1):68-77.
[8]乔陶鹏,严普强,邓焱,等.斜拉索索力估算中振动信号处理方法的改进[J].清华大学学报:自然科学版,2003,43(5):644-647.QIAO Tao-peng,YAN Pu-qiang,DENG Yan,et al.Data Processing of Vibration Signals for Cable Ten-sion Estimation[J].Journal of Tsinghua University:Science and Technology,2003,43(5):644-647.
[9]魏建东.索力测定常用公式精度分析[J].公路交通科技,2004,21(2):53-56.WEI Jian-dong.Precision Analysis of ConventionalFormulas Calculating Cable Tension[J].Journal ofHighway and Transportation Research and Develop-ment,2004,21(2):53-56.
[10]程磊,瞿伟廉.基于Hilbert-Huang变换理论的非平稳数据处理[J].建筑科学与工程学报,2007,24(1):26-30.CHENG Lei,QU Wei-lian.Non-stationary Data Pro-cessing Based on Hilbert-Huang Transform Theory[J].Journal of Architecture and Civil Engineering,2007,24(1):26-30.
[11]陈刚,任伟新.基于环境振动的斜拉索基频识别[J].地震工程与工程振动,2003,23(3):100-106.CHEN Gang,REN Wei-xin.Ambient Vibration BasedIdentification of Fundamental Frequencies of StayCables[J].Earthquake Engineering and EngineeringVibration,2003,23(3):100-106.