Modal-Parameter Identification From Nonstationary Ambient Vibration Data

2011 ◽  
pp. 157-169
Author(s):  
Dar-Yun Chiang ◽  
Chang-Sheng Lin
Keyword(s):  
Parameter Identification ◽  
Ambient Vibration ◽  
Modal Parameter ◽  
Modal Parameter Identification ◽  
Vibration Data ◽  
Nonstationary Ambient Vibration

Modal Parameter Identification of Hagia Sophia Bell-Tower via Ambient Vibration Test

2009 ◽  
Vol 28 (1) ◽  
pp. 37-47 ◽  
Author(s):  
Alemdar Bayraktar ◽  
Temel Türker ◽  
Barış Sevım ◽  
Ahmet Can Altunişik ◽  
Faruk Yildirim
Keyword(s):  
Parameter Identification ◽  
Ambient Vibration ◽  
Vibration Test ◽  
Modal Parameter ◽  
Ambient Vibration Test ◽  
Modal Parameter Identification ◽  
Bell Tower ◽  
Hagia Sophia

Consistent Multilevel RDT-ERA for Output-Only Ambient Modal Identification of Structures

2017 ◽  
Vol 17 (09) ◽  
pp. 1750106 ◽  
Author(s):  
Zhouquan Feng ◽  
Wenai Shen ◽  
Zhengqing Chen
Keyword(s):  
Parameter Identification ◽  
Modal Identification ◽  
Ambient Vibration ◽  
Weighted Averaging ◽  
Modal Parameters ◽  
Modal Parameter ◽  
Consistency Analysis ◽  
Modal Parameter Identification ◽  
Random Decrement Technique ◽  
Random Decrement

This paper presents an improved method called the consistent multilevel random decrement technique in conjunction with eigensystem realization algorithm (RDT-ERA) for modal parameter identification of linear dynamic systems using the ambient vibration data. The conventional RDT-ERA is briefly revisited first and the problem of triggering level selection in the RDT is thoroughly studied. Due to the use of a single triggering level by the conventional RDT-ERA, an inappropriate triggering level may produce poor random decrement (RD) functions, thereby yielding a poor estimate of modal parameters. In the proposed consistent multilevel RDT-ERA, multiple triggering levels are used and a consistency analysis is proposed to sift out the RD functions that deviate largely from the majority of the RD functions. Then the ERA is applied to the retained RD functions for modal parameter identification. Subsequently, a similar consistency analysis is conducted on the identified modal parameters to sift out the outliers. Finally, the final estimates of the modal parameters are calculated using weighted averaging with the weights set proportional to the number of RD segments extracted from the corresponding triggering levels. The proposed method is featured by the fact that the information from the signal is fully utilized using multiple triggering levels and the outliers are sifted out using consistency analysis, thus making the identified result more accurate and reliable. The effectiveness and accuracy of the method have been demonstrated in the examples using the simulated data and experimental data.

scholarly journals Modal Parameter Identification Based on Hilbert Vibration Decomposition in Vibration Stability of Bridge Structures

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Yingzhi Xia ◽  
Hui Li ◽  
Zhezhe Fan ◽  
Jiyong Xiao
Keyword(s):  
Parameter Identification ◽  
Ambient Vibration ◽  
Frequency Resolution ◽  
Response Analysis ◽  
Modal Parameter ◽  
Model Decomposition ◽  
Modal Parameter Identification ◽  
Ambient Vibration Tests ◽  
Identification Technique ◽  
Output Only

Modal parameters are important parameters for the dynamic response analysis of structures. An output-only modal parameter identification technique based on Hilbert Vibration Decomposition (HVD) is developed herein for structural modal parameter identification to (1) obtain the Free Decay Response (FDR) of a structure through free vibration or ambient vibration tests, (2) decompose the FDR into modal responses using HVD, and (3) calculate the instantaneous frequencies and instantaneous damping ratios of the modal responses to obtain the modal frequencies and modal damping ratios. A series of numerical examples are examined to demonstrate the efficiency and highlight the superiorities of the proposed method relative to the empirical model decomposition-based (EMD-based) method. The robustness of the proposed method to noises is also investigated and proved to be positive effect. The proposed method is proved to be efficient in modal parameter identification for both linear and nonlinear systems, with better frequency resolution, and it can be applied to systems with closely spaced modes and low-energy mode.

Modal parameter identification of a containment using ambient vibration measurements

2010 ◽  
Vol 240 (3) ◽  
pp. 453-460 ◽  
Author(s):  
Sanghyun Choi ◽  
Sooyong Park ◽  
Chang-Hun Hyun ◽  
Moon-Soo Kim ◽  
Kang-Ryong Choi
Keyword(s):  
Parameter Identification ◽  
Ambient Vibration ◽  
Modal Parameter ◽  
Vibration Measurements ◽  
Modal Parameter Identification ◽  
Ambient Vibration Measurements

Study of Modal Parameter Identification from Ambient Vibration on a Deep Radial Gate

2011 ◽  
Vol 105-107 ◽  
pp. 511-517
Author(s):  
Yuan Qi Cai ◽  
Ke Zhang
Keyword(s):  
Parameter Identification ◽  
Modal Analysis ◽  
Damping Ratio ◽  
Modal Identification ◽  
Ambient Vibration ◽  
Modal Parameter ◽  
Modal Parameter Identification ◽  
Flood Discharge ◽  
Prototype Test ◽  
Radial Gate

In the engineering background of the prototype test of a deep radial gate on three gorges dam, two methods are provided for the modal parameter identification of the radial gate, one is applying operation modal analysis (OMA) to a gate which is under flood discharge, the other one is applying experiment modal analysis (EMA) to a inactive gate with some other gates under flood discharge. This paper is based on the feasibility study on the former method. We use the natural excitation technology (NExT) combined with the eigensystem realization algorithm (ERA) to determine the dynamic characteristics of a gate. Displacement data at 7 locations were processed using NExT-ERA to extract the natural frequency and associated damping ratio. The results show the effectiveness of this modal identification methodology and the possibility of implementing it on other hydraulic structure.

Sign in / Sign up

Export Citation Format

Share Document