桥梁建设
橋樑建設
교량건설
BRIDGE CONSTRUCTION
2015年
2期
26-31
,共6页
桥梁工程%吊拉组合桥%时频域%模态参数%模型试验%阻尼比%自振频率%模态识别
橋樑工程%弔拉組閤橋%時頻域%模態參數%模型試驗%阻尼比%自振頻率%模態識彆
교량공정%조랍조합교%시빈역%모태삼수%모형시험%조니비%자진빈솔%모태식별
bridge engineering%combined cable-stayed and suspension bridge%time-frequen-cy domain%modal parameter%model test%damping ratio%natural vibration frequency%modal i-dentification
为在时频域内识别桥梁结构的模态参数，针对HHT （Hilbert‐Huang Transform）方法识别桥梁结构模态参数中存在的端点效应、模态混叠以及频率识别与阻尼识别相互耦合现象，应用带通滤波和扩展随机减量法对HHT方法进行改进，建立了一种基于现代信号时频域分析的桥梁结构模态参数识别方法，然后基于MATLAB平台，编制了桥梁结构模态参数时频域识别程序，并以某吊拉组合桥梁全桥模型试验为例，利用实测数据对所提方法进行验证。结果表明，该方法能正确识别出模型桥梁的前11阶竖向自振频率、前6阶阻尼比以及前3阶模态振型；阻尼比的识别结果为0．2％～2％；识别结果与有限元模型修正后的计算结果相差不大。所提方法能正确、有效地在时频域内识别桥梁结构的频率、阻尼及模态等参数。
為在時頻域內識彆橋樑結構的模態參數，針對HHT （Hilbert‐Huang Transform）方法識彆橋樑結構模態參數中存在的耑點效應、模態混疊以及頻率識彆與阻尼識彆相互耦閤現象，應用帶通濾波和擴展隨機減量法對HHT方法進行改進，建立瞭一種基于現代信號時頻域分析的橋樑結構模態參數識彆方法，然後基于MATLAB平檯，編製瞭橋樑結構模態參數時頻域識彆程序，併以某弔拉組閤橋樑全橋模型試驗為例，利用實測數據對所提方法進行驗證。結果錶明，該方法能正確識彆齣模型橋樑的前11階豎嚮自振頻率、前6階阻尼比以及前3階模態振型；阻尼比的識彆結果為0．2％～2％；識彆結果與有限元模型脩正後的計算結果相差不大。所提方法能正確、有效地在時頻域內識彆橋樑結構的頻率、阻尼及模態等參數。
위재시빈역내식별교량결구적모태삼수，침대HHT （Hilbert‐Huang Transform）방법식별교량결구모태삼수중존재적단점효응、모태혼첩이급빈솔식별여조니식별상호우합현상，응용대통려파화확전수궤감량법대HHT방법진행개진，건립료일충기우현대신호시빈역분석적교량결구모태삼수식별방법，연후기우MATLAB평태，편제료교량결구모태삼수시빈역식별정서，병이모조랍조합교량전교모형시험위례，이용실측수거대소제방법진행험증。결과표명，해방법능정학식별출모형교량적전11계수향자진빈솔、전6계조니비이급전3계모태진형；조니비적식별결과위0．2％～2％；식별결과여유한원모형수정후적계산결과상차불대。소제방법능정학、유효지재시빈역내식별교량결구적빈솔、조니급모태등삼수。
To identify the modal parameters of bridge structure in the time‐frequency domain , the existing HHT (Hilbert‐Huang Transform) method was improved by the band‐pass filtering and extended random decrement methods ,considering that the problems of the end effect ,modal mixture and the coupling identification of frequency and damping would occur as the HHT method was used to identify the modal parameters .A kind of the new method for the modal parameter i‐dentification of bridge structure was established based on the contemporary signal time‐frequency domain analysis and on the MATLAB platform ,the program of the modal parameter identification of bridge structure in the time‐frequency domain was complied .By way of example of the whole bridge model test of a combined cable‐stayed and suspension bridge ,the new method w as checked and verified by the measured data .T he results of the verification show that the method can be used to correctly identify the first 11 orders of the vertical natural vibration frequencies ,first 6 orders of the damping ratios and first 3 orders of the modal vibration shapes of the model bridge .T he identi‐fication results of the damping ratios are 0 .2% ~2% and do not differ much from the calculation results updated by the finite element model .T he method can correctly and effectively identify the parameters of the frequencies ,damping and modal vibration shapes of bridge structure in the time‐frequency domain .
