Extraction of real modes and physical matrices from modal testing
A technique to extract real modes from the identified complex modes is presented in this paper, which enables the normalized real mode shapes, modal masses, and full or reduced mass and stiffness matrices to be obtained. The theoretical derivation of the method is provided in detail. An 11-DOF vibration system is used to validate the algorithm, and to analyze the effects of the number of modes utilized and measurement DOFs on the extraction results. Finally, the method is used to extract real modes from both experimental modal analysis and operational modal analysis.
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- Extraction of real modes and physical matrices from modal testing
Earthquake Engineering and Engineering Vibration
Volume 10, Issue 2 , pp 219-227
- Cover Date
- Print ISSN
- Online ISSN
- Institute of Engineering Mechanics, China Earthquake Administration
- Additional Links
- modal analysis
- complex mode
- real mode
- normalized mode shape
- modal mass
- Author Affiliations
- 1. MOE Key Lab of Structural Mechanics and Control for Aircraft, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China
- 3. Institute of Vibration Engineering, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing, 210016, China
- 2. Department of Civil Engineering, University of Greenwich, Greenwich, UK