This paper presents a procedure of establishing the discrete equations of motion for a structure via wavelet packet method from its measured responses and inputs. Then, the natural frequencies, damping ratios and mode shapes of the structure can be directly determined. The proposed procedure is applied to process the acceleration responses of a five-story steel frame, subjected to 8%, 20%, 40%,...

As a linear system identification method developed in recent years, Random Subspace Algorithm (SSI) can effectively extract modal parameters from environmental incentive structure. However, this algorithm is not suitable for the embedded system due to its long calculation and low efficiency. For this consideration, improved from the data-based classical stochastic subspace algorithm, this artic...

This paper is concerned with the determination of optimal sensor locations for structural modal identification in a strap-braced cold formed steel frame based on an improved genetic algorithm (IGA). Six different optimal sensor placement performance indices have been taken as the fitness functions two based on modal assurance criterion (MAC), two based on maximization of the determinant of a Fi...

This paper presents a recursive method of modal parameters identification based on operational measurements, dedicated for non-stationary systems. Decoupling signal components procedure allowed to reduce the signal model and simplified the process of modal parameters estimation. Adaptive method of filtering simplified the process of wavelet function selection. Presented method utilize Continuou...

Parametric identification of viscous damping models in the context of linear vibration theory is studied. Frequency domain identification methods based on measured frequency response functions (FRFs) are considered. Existing methods are classified into two main groups: matrix methods which use directly the measured FRF matrix, and modal methods which use modal parameters deduced from the FRFs. ...

Linear system identification is an important and useful approach in experimental modal analysis. It allows for the extraction of resonance frequencies, damping ratios and mode shapes of a vibrating structure. In order to reduce the bias on the estimates, the model order is usually chosen quite high. This often results in the appearance of non-physical, or so-called spurious modes. In this paper...