振动与冲击
振動與遲擊
진동여충격
JOURNAL OF VIBRATION AND SHOCK
2015年
18期
195-199
,共5页
Hilbert-Huang 变换%总体经验模态分解%瞬时频率%损伤识别
Hilbert-Huang 變換%總體經驗模態分解%瞬時頻率%損傷識彆
Hilbert-Huang 변환%총체경험모태분해%순시빈솔%손상식별
hilbert-huang transform%ensemble empirical mode decomposition%instantaneous frequency%damage detection
针对Hilbert-Huang变换(HHT)在信号处理中存在的模态混叠的问题,引入总体经验模态分解(EEMD)对HHT 方法进行改进,并将改进的 HHT 方法应用于工程结构损伤识别中。建立一个三自由度剪切型结构模型,结构刚度退化模型采用双线性刚度退化模型,计算结构在地震作用下的响应,对结构加速度响应进行改进的 HHT 分析,提出了利用损伤前后结构响应一阶固有模态函数(IMF)特征能量比识别结构损伤位置的方法。结果表明:通过结构响应瞬时频率的变化可以判断结构是否损伤和出现损伤的时间,根据损伤前后各层一阶 IMF 能量比的变化可以识别损伤的位置。将改进的 HHT 应用到对实际工程的强震记录分析中,通过提取一阶瞬时频率和一阶 IMF 特征能量比较好地识别了结构在强震作用下的损伤。
針對Hilbert-Huang變換(HHT)在信號處理中存在的模態混疊的問題,引入總體經驗模態分解(EEMD)對HHT 方法進行改進,併將改進的 HHT 方法應用于工程結構損傷識彆中。建立一箇三自由度剪切型結構模型,結構剛度退化模型採用雙線性剛度退化模型,計算結構在地震作用下的響應,對結構加速度響應進行改進的 HHT 分析,提齣瞭利用損傷前後結構響應一階固有模態函數(IMF)特徵能量比識彆結構損傷位置的方法。結果錶明:通過結構響應瞬時頻率的變化可以判斷結構是否損傷和齣現損傷的時間,根據損傷前後各層一階 IMF 能量比的變化可以識彆損傷的位置。將改進的 HHT 應用到對實際工程的彊震記錄分析中,通過提取一階瞬時頻率和一階 IMF 特徵能量比較好地識彆瞭結構在彊震作用下的損傷。
침대Hilbert-Huang변환(HHT)재신호처리중존재적모태혼첩적문제,인입총체경험모태분해(EEMD)대HHT 방법진행개진,병장개진적 HHT 방법응용우공정결구손상식별중。건립일개삼자유도전절형결구모형,결구강도퇴화모형채용쌍선성강도퇴화모형,계산결구재지진작용하적향응,대결구가속도향응진행개진적 HHT 분석,제출료이용손상전후결구향응일계고유모태함수(IMF)특정능량비식별결구손상위치적방법。결과표명:통과결구향응순시빈솔적변화가이판단결구시부손상화출현손상적시간,근거손상전후각층일계 IMF 능량비적변화가이식별손상적위치。장개진적 HHT 응용도대실제공정적강진기록분석중,통과제취일계순시빈솔화일계 IMF 특정능량비교호지식별료결구재강진작용하적손상。
Aiming at the problem of mode mixing in signal analysis by using Hilbert-Huang transform(HHT),an improved HHT method based on ensemble empirical mode decomposition (EEMD)was introduced and applied in the identification of structural damages.A three degrees of freedom bilinear stiffness degradation model of shear type structure was established.Structural responses under earthquake were calculated and analyzed by the improved HHT.A method to detect the location of damage based on intrinsic mode function (IMF)energy was proposed.It is shown that whether or not a structure is damaged and when the damage occurs can be decided by an instantaneous frequency change of structural acceleration and the location of damage is detected by the variation of corresponding IMF energy at the first modal frequency of structural response before and after damage.The damage of an actual engineering under earthquake can be well identified by extracting the first modal instantaneous frequency and the first modal IMF energy.