Damage assessment on frame structure with bolted joints based on experimental modal analysis

Nowadays, damping is still the important dynamic characteristic that is the least understood and the most difficult to quantify. The advantage of the proposed damping matrix identification method is that several low order complex modes achieved by Experimental Modal Analysis (EMA) are capable of calculation precision. In order to identify the damping matrix, this paper also proposes a general damping matrix decompositon technique, which can be used in the situation that different parts of the structure have different damping. Then a five-story frame structure is applied to demonstrate the proposed method ,and the results obtained show the suitability of this approach for damping matrix identification in frame structures.

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Effect of Bass Bar Tension on Modal Parameters of a Violin's Top Plate

Archives of Acoustics ◽

10.2478/aoa-2014-0015 ◽

2015 ◽

Vol 39 (1) ◽

pp. 145-149 ◽

Cited By ~ 3

Author(s):

Ewa B. Skrodzka ◽

Bogumił B.J. Linde ◽

Antoni Krupa

Keyword(s):

Modal Analysis ◽

Experimental Modal Analysis ◽

Mode Shapes ◽

Modal Parameters ◽

Normal Value ◽

Modal Damping

Abstract Experimental modal analysis of a violin with three different tensions of a bass bar has been performed. The bass bar tension is the only intentionally introduced modification of the instrument. The aim of the study was to find differences and similarities between top plate modal parameters determined by a bass bar perfectly fitting the shape of the top plate, the bass bar with a tension usually applied by luthiers (normal), and the tension higher than the normal value. In the modal analysis four signature modes are taken into account. Bass bar tension does not change the sequence of mode shapes. Changes in modal damping are insignificant. An increase in bass bar tension causes an increase in modal frequencies A0 and B(1+) and does not change the frequencies of modes CBR and B(1-).

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Damage evaluation of sandwich material on side plate hull using experimental modal analysis

Materials Today Proceedings ◽

10.1016/j.matpr.2021.04.293 ◽

2021 ◽

Author(s):

R.C. Ariesta ◽

A. Zubaydi ◽

A. Ismail ◽

T. Tuswan

Keyword(s):

Modal Analysis ◽

Experimental Modal Analysis ◽

Damage Evaluation ◽

Side Plate

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On the use of experimental modal analysis for system identification of a railway pantograph

International Journal of Rail Transportation ◽

10.1080/23248378.2020.1786743 ◽

2020 ◽

pp. 1-12

Author(s):

Petter Nåvik ◽

Stefano Derosa ◽

Anders Rønnquist

Keyword(s):

System Identification ◽

Modal Analysis ◽

Experimental Modal Analysis

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The Use of Modan 3D in Experimental Modal Analysis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.486.36 ◽

2013 ◽

Vol 486 ◽

pp. 36-41 ◽

Cited By ~ 3

Author(s):

Róbert Huňady ◽

František Trebuňa ◽

Martin Hagara ◽

Martin Schrötter

Keyword(s):

Modal Analysis ◽

Vibration Analysis ◽

High Speed ◽

Mechanical Vibration ◽

Steel Sample ◽

Experimental Modal Analysis ◽

Image Correlation ◽

Optical Methods ◽

Mode Shapes ◽

Vibration Modes

Experimental modal analysis is a relatively young part of dynamics, which deals with the vibration modes identification of machines or their parts. Its development has started since the beginning of the eighties, when the computers hardware equipment has improved and the fast Fourier transform (FFT) could be used for the results determination. Nowadays it provides an uncountable set of vibration analysis possibilities starting with conventional contact transducers of acceleration and ending with modern noncontact optical methods. In this contribution we mention the use of high-speed digital image correlation by experimental determination of mode shapes and modal frequencies. The aim of our work is to create a program application called Modan 3D enabling the performing of experimental modal analysis and operational modal analysis. In this paper the experimental modal analysis of a thin steel sample performed with Q-450 Dantec Dynamics is described. In Modan 3D the experiment data were processed and the vibration modes were determined. The reached results were verified by PULSE modulus specialized for mechanical vibration analysis.

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