Operational modal analysis of an eleven-span concrete bridge subjected to weak ambient excitations

Chen, Ge-Wei; Omenzetter, Piotr; Beskhyroun, Sherif

doi:10.1016/j.engstruct.2017.08.066

Cited by 50 publications

(36 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This idea of averaging corresponds to the PP-CA algorithm, in which this operation is inherent at the procedure start, where the measured signal is split into n d parts; next the spectral functions are computed as averages over the n d signal set (see Eqs. 7,8).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Study on applicability of two modal identification techniques in irrelevant cases

Tomaszewska

Szafrański

2020

Archiv.Civ.Mech.Eng

View full text Add to dashboard Cite

Study on applicability of two modal identification techniques in irrelevant cases is made in this paper. The following techniques are considered: peak picking based on correlation analysis (PP-CA), dedicated for ambient vibrations and eigensystem realization algorithm (ERA), formulated for free-decay vibrations investigation. Irrelevant cases are found when analyzed signals are different than recommended to a given technique. The study is conducted on examples of two real structures: masonry tower and steel railway bridge. Both cases are diverse in age, material, excitation and vibrations energy. The signals measured on the tower are suitable for the PP-CA technique (ambient vibrations), while the signals measured on the bridge are suitable for the ERA (free-decay vibrations). However, both methods have been applied to both systems. Natural frequencies, mode shapes and damping ratios are identified and the effectiveness of the irrelevant technique is assessed in relation to the results obtained by the relevant method in each case.

show abstract

Section: Discussionmentioning

confidence: 99%

“…In the Ref. [7], the PP method is used for modal identification of the multi-span concrete Nelson St. bridge in Auckland (New Zealand). Resonant frequencies are identified using the averaged normalized power spectral density function (ANPSD) calculated for the measured ambient responses of the bridge deck.…”

Section: Introductionmentioning

confidence: 99%

Study on applicability of two modal identification techniques in irrelevant cases

Tomaszewska

Szafrański

2020

Archiv.Civ.Mech.Eng

View full text Add to dashboard Cite

show abstract

“…Applications of OMA methods are described by numerous authors, including Oliveira et al [55] who reported on the continuous monitoring of an onshore wind turbine using the SSI-COV and P-LSCF methods, and Chen at al. [56] who used the SSI-Data and FDD techniques in the OMA of a multi-span concrete bridge. The ESA Vega launcher was investigated using OMA by De Vivo et al [57], and Chomette and Carrou [58] studied the modes of a concert harp.…”

Section: Frequency-domain Methodsmentioning

confidence: 99%

Basis-updating for data compression of displacement maps from dynamic DIC measurements

Chang

Wang

Siebert

et al. 2019

Mechanical Systems and Signal Processing

View full text Add to dashboard Cite

The extraction of useful information and removal of redundant noise from data has become a major research topic in recent years. Data compression is necessary for all kinds of analysis, and the demand for efficient compression techniques has gained much attention. Digital image correlation is a camera-based measuring system, which has been widely applied in strain analysis because of the convenience of measuring displacement fields by simply selecting a region of interest. Currently, there is interest in applying such methods to engineering structures in dynamics. However, one of the major issues related to the integration of camera-based systems with dynamic measurement is the generation of huge amounts of data, typically extending to many thousands of data points, because of the requirements of high sampling rate, spatial resolution, and long duration of recording. In this paper a new algorithm is presented that addresses the need for efficiency in full-field data processing. By making use of the data itself and combining the concept of sparse representation with Gram-Schmidt orthogonalisation, the number of basis function used to represent the data can be reduced and a concise decomposition established. In both simulated and experimental cases, the compression ratios for data size and number of signals used in operational modal analysis are substantially diminished, thereby demonstrating the effectiveness of the proposed algorithm. A reduced number of new basis functions is determined for the representation of data under the condition that the reconstructed displacement map reproduces the raw measured data to within a chosen threshold on the coefficient of correlation.

show abstract

“…The system identification results can be validated by using two methods-by comparing the frequencies of the analytical and experimental modes and by comparing the Mode shapes using the Modal Assurance Criterion (MAC) [34]. MAC is a quantitative measure between two vectors used to compare the experimental and analytical mode shape vectors.…”

Section: Comparison Of Finite Element Model and System Identificationmentioning

confidence: 99%

Ambient Vibration Testing of a Pedestrian Bridge Using Low-Cost Accelerometers for SHM Applications

2019

View full text Add to dashboard Cite

Damage detection and structural health monitoring have always been of great importance to civil engineers and researchers. Vibration-based damage detection has several advantages compared to traditional methods of non-destructive evaluation, such as ground penetrating radar (GPR) or ultrasonic testing, since they give a global response and are feasible for large structures. Damage detection requires a comparison between two systems states, the baseline or “healthy state”, i.e., the initial modal parameters, and the damaged state. In this study, system identification (SI) was carried out on a pedestrian bridge by measuring the dynamic response using six low-cost triaxial accelerometers. These low-cost accelerometers use a micro-electro-mechanical system (MEMS), which is cheaper compared to a piezoelectric sensor. The frequency domain decomposition algorithm, which is an output-only method of modal analysis, was used to obtain the modal properties, i.e., natural frequencies and mode shapes. Three mode shapes and frequencies were found out using system identification and were compared with the finite element model (FEM) of the bridge, developed using the commercial finite element software, Abaqus. A good comparison was found between the FEM and SI results. The frequency difference was nearly 10%, and the modal assurance criterion (MAC) of experimental and analytical mode shapes was greater than 0.80, which proved to be a good comparison despite the small number of accelerometers available and the simplifications and idealizations in FEM.

show abstract

Operational modal analysis of an eleven-span concrete bridge subjected to weak ambient excitations

Cited by 50 publications

References 32 publications

Study on applicability of two modal identification techniques in irrelevant cases

Study on applicability of two modal identification techniques in irrelevant cases

Basis-updating for data compression of displacement maps from dynamic DIC measurements

Ambient Vibration Testing of a Pedestrian Bridge Using Low-Cost Accelerometers for SHM Applications

Contact Info

Product

Resources

About