A Combined Approach to Estimate Modal Parameters for Updating the Finite Element Model of a High-Rise Building

Abstract

Accurate estimation of modal parameters is crucial for various aspects of tall buildings, including structural design, vibration control, and state assessment. This paper first presents a combined approach for the structural modal parameter estimation by combining the empirical wavelet transform (EWT), smoothed discrete energy separation algorithm-1 (SDESA-1), and half-cycle energy operator (HCEO), referred to as EWT-SH. A numerical study on a five-story frame structure is conducted using the Newmark-β method to validate its effectiveness and accuracy. The results demonstrate that relative errors in estimating the natural frequency and damping ratio using the EWT-SH method are significantly smaller compared to traditional methods. Furthermore, the EWT-SH method is applied to estimate the modal parameters of a real super-tall building, i.e., the SEG Plaza building in Shenzhen, using acceleration responses. Identified results confirm the applicability and accuracy of the EWT-SH method in real-world scenarios and indicate that the frequencies and damping ratios of the SEG Plaza building noticeably decrease after 20 years of service, which could partially explain the SEG building vibration event on May 18, 2021. Since the identified frequencies are quite different from those of the original finite element (FE) model of the tall building, the dual-loop particle swarm optimization (PSO) is specifically developed to update the FE model of SEG Plaza building.