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Dynamic performance verifcation of the Rędziński Bridge using portable camera‑based vibration monitoring systems

Bocian Mateusz, Nikitas Nikolaos, Kalybek Maksat, Kużawa Mieszko, Hawryszków Paweł, Bień Jan, Onysyk Jerzy, Biliszczuk Jan

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 1

art. no. e40, 2023

EN

The assessment of dynamic performance of large-scale bridges typically relies on the deployment of wired instrumentation systems requiring direct contact with the tested structures. This can obstruct their operation and create unnecessary risks to the involved personnel and equipment. These problems can be readily avoided by using non-contact instrumentation systems. However, the cost of of-the-shelf commercial products often prevents their wide adoption in engineering practice. To this end, the dynamic performance of the biggest one-pylon cable-stayed bridge in Poland is investigated based on data from a consumer-grade digital camera and open access image-processing algorithms. The quality of these data is benchmarked against data obtained from conventional wired accelerometers and a high-end commercial optical motion capture system. Operational modal analysis is conducted to extract modal damping, which has a potential to serve as an indicator of structural health. The dynamic properties of the bridge are evaluated against the results obtained during a proof loading exercise undertaken prior to the bridge opening. It is shown that a vibration monitoring system based on consumer-grade digital camera can indeed provide an economically viable alternative to monitoring the complex time-evolving dynamic behaviour patterns of large-scale bridges.

2

The Effect of the Cavity Damping on Vehicular Evaluation using the Finite Element Method

Ferreira T. S., Magalhães P. A., Moura F. L., Ferreira T. S.

Archives of Acoustics

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2016

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Vol. 41, No. 1

87--97

EN

This work focuses on finding a numerical solution for vehicle acoustic studies and improving the usefulness of the numerical experimental parameters for the development stage of a new automotive project. Specifically, this research addresses the importance of modal cavity damping for vehicle exerts during numerical studies. It then seeks to suggest standardized parameter values of modal cavity damping in vehicular acoustic studies. The standardized value of modal cavity damping is of great importance for the study of vehicular acoustics in the automotive industry because it would allow the industry to begin studies of the acoustic performance of a new vehicle early in the conception phase with a reliable estimation that would be close to the final value measured in the design phase. It is common for the automotive industry to achieve good levels of numerical-experimental correlation in acoustic studies after the prototyping phase because this phase can be studied with feedback from the simulation and experimental modal parameters. Thus, this research suggests values for modal cavity damping, which are divided into two parts due to their behaviour: ξ(x) = −0.0126(x − 100) + 6.15 as a variable function to analyse up to 100 Hz and 6.15% of modal cavity damping constant for studies between 30 Hz and 100 Hz. The sequence of this study shows how we arrived at these values.

3

Vibration based damage detection using Laplace wavelet

Majkut L.

Diagnostyka

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2009

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nr 1(49)

79-82

EN

In work the Laplace wavelet definition is given and it utilization to the damage diagnostics. The Laplace wavelet is a complex, analytic damped exponential wavelet and it is desirable wavelet basis to analyze signals of impulse response. A correlation filtering approach is introduced using the Laplace wavelet to identifying the modal parameters from vibration signals. Considered in work damage were: small crack in steel beam and change (the decrease) the tension force in the prestressed element. Based on simulated (cracked beam) and measured (prestressed beam) signals the natural frequencies and modal damping ratios have been determined.

PL

W pracy podano definicję falki Laplace'a i sposób jej wykorzystania do celów diagnostyki uszkodzeń. Falka Laplace'a jest to pewna analityczna, zespolona i tłumiona funkcja wykładnicza co ułatwia analizę sygnałów odpowiedzi impulsowych. Dla tak zdefiniowanej falki zastosowano filtrowanie korelacyjne co pozwala na wyznaczenie parametrów modalnych analizowanego układu, na podstawie analizy jego odpowiedzi impulsowej. Analizowanymi uszkodzeniami były: "małe" pęknięcie w belce prostoliniowej i zmiana siły sprężającej w elemencie wstępnie sprężonym.

4

Experimental modal analysis of a railway wheelset

Ondrouch J., Chrapkova A.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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1998

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z. 7

273-282

EN

The paper deals with estimation of dynamic properties of railway wheelsets by means of experimental modal analysis. Eigenfrequencies , eigenmodes and modal damping have been obtained from the measured data. On the basis of knowledge of these properties, an assessment of vibration and noise produced by wheelsets during operation have been carried out.

PL

Artykuł poświęcony jest wyznaczaniu właściwości dynamicznych kolejowego zestawu kołowego przy pomocy eksperymentalnej analizy modalnej . Pomiarem zostały określone częstości i postacie własne drgań oraz tłumienie modalne. Na podstawie uzyskanych danych są rozpatrywane wibracje i hałas kolejowego zestawu kołowego podczas pracy.