Application of EMMD in Modal Parameter Identification of Structures under Ambient Excitation

This paper mainly provides a modal parameter identification method based on combination of extremum field mean mode decomposition (EMMD) and random decrement technique (RDT), which is applied to structures under ambient excitation. In this method, firstly, a number of intrinsic mode functions (IMFs) are decomposed from acceleration response of structure under ambient excitation by using EMMD. Next, the RDT is applied to calculate response of free vibration for each IMF, and then identify the modal parameters from free vibration response. The principle and concrete steps of the method are given in this paper, and the feasibility and validity of this method are demonstrated through a emulation experiment.