Abstract:Aiming at suppressing mode mixing in the traditional empirical mode decomposition (EMD) method, a combined method called as FM-CEEMD based on the complementary ensemble empirical mode decomposition (CEEMD) and signal frequency modulation (FM) methods was proposed considering the generating mechanism of mode mixing.The effectiveness of the combined decomposition method was verified by using simulation signals.The modified mode decomposition method was then applied to the Hilbert-Huang Transform (HHT), replacing the traditional EMD method, in order to obtain an improved HHT structural dynamic parameter identification method for suppressing mode mixing.The identified results both from the simulation experiment and an actual arch dam show the improved HHT method can not only avoid the loss of modal information to improve the parameter identification accuracy, but also be suitable to the researches on the structural modal identification of real hydraulic projects.
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