Multi-taper method based substructure identification for shear structures

Abstract

Quickly and accurately identifying structural status after natural disasters plays crucial roles in disaster rescue. Previously, the authors developed a substructure identification method for shear structures, which uses the frequency responses of short structural acceleration responses to estimate structural parameters inductively. However, the numerical studies found that the method could only provide moderately accurate results. In this paper, a thorough uncertainty analysis is performed to reveal the key factors that influence its identification accuracy. Based on these results, a new substructure method is proposed herein, which utilizes the cross power spectrum densities of structural responses, estimated by the multi-taper method, to formulate substructure identification problems. The error analysis is also conducted for the multi-taper method based method, explaining why this method can significantly improve identification accuracy, compared with the frequency response based method. Moreover, although the multi-taper method based method is originally derived based on stationary structural responses, a further analysis shows that it can be extended to non-stationary responses, greatly broadening the method’s application range. Finally, the simulation study of a 20-story shear structure and the shake table tests on a three-story bench-scaled structure are conducted, which verified that the proposed multi-taper method based method indeed significantly improves the substructure identification accuracy.

Receptance coupling substructure analysis based FRF modeling for multi-segment shell with nonlinear joint interface

“…Yu et al proposed a method to obtain the stiffness and mass matrix of variable cross-section parts, and obtained the FRF at the tool tip by combining RCSA (Yu et al, 2020). In addition to the application of RCSA in machine tool field, many scholars have extended this method to other engineering fields (Zhang et al, 2020; Chen et al, 2011; Wang et al, 2015). For example, Liu et al used RCSA to establish the dynamics model of the flywheel-bearing-shell coupling system, and obtained the output characteristics of the flywheel at different rotational speeds (Liu et al, 2019).…”

Online parameter estimation and adaptive control with limited information in structures

“…Also, other identification methods, such as the extended Kalman filter (EKF) method, have been conducted to identify the characteristics of the MR damper (Su et al, 2018), identify structural parameters with unknown inputs (Liu et al, 2016), and combine the EKF-WGI and WAI algorithms (Xu and He, 2015). Researchers also suggested a decentralized identification with KF and Newton-SOR (Ni et al, 2018), an identification using modal information and KF-limited measurement (Li et al, 2019), and multi-taper method–based substructure identification (Zhang et al, 2020).…”