A combined method of Wigner-Ville distribution with a theoretical model for acoustic emission source location in a dispersive media

Kim, Jin-Seop; Choi, Young‐Chul; Choi, Jongwon; Cho, Gye-Chun

doi:10.1007/s12205-013-0418-6

Cited by 10 publications

(5 citation statements)

References 21 publications

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“…It has unique properties, such as high energy accumulation and high resolution in time and frequency, and provides superior component concentration for signal processing . In addition, with this distribution, one can extract useful information, such as group delay and instantaneous frequency from the signal . WVD is defined as follows:

{WVD}_{z} ((),, t, f) = F_{τ \to f} ({}, K_{z} ((),, t, τ)),

in which F is the Fourier transform and

K_{z} ((),, t, τ) = z ((), t + \frac{true}{τ}) z^{*} ((), t - \frac{true}{τ})

is the signal kernel.…”

Section: Square Time–frequency Distributionsmentioning

confidence: 99%

New damage index based on least squares distance for damage diagnosis in steel girder of bridge's deck

Ahmadi

Anvari

2018

Struct Control Health Monit

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An increase in the number of incidents involving steel bridges in recent years has made it necessary to analyze their safety. So far, researchers have proposed several methods to determine the dynamic behavior of steel bridges, distinguish changes in their behavior, extract dynamic specification, and detect damage in them. In this study, an applied algorithm and a new damage index based on the time-frequency matrix and least squares distance have been proposed and used to determine the damage and detect its location. The performance of the suggested index to identify the damage in the numerical model of two steel beams with 31 damage scenarios was investigated. In addition, the LS-Index was assessed for damage diagnosis in the analytical model of the College Bridge. The finite element model of the College Bridge was created based on extensive in situ measurements and laboratory tests, and 10 different damage scenarios were considered. The results showed the ability of the proposed index to identify damage in the girder of the bridge. The obtained results suggested that the index can also report the damage simultaneously. The performance of the proposed method was also investigated using noise-polluted signals with three different signal-to-noise ratios. Based on the calculations, the index had a good performance. To diagnose damage, there is no need to measure the input loading. Besides, it is not necessary to create a numerical model. Owing to the applicability, accuracy, and high ability, the damage index can be used to detect damage in the steel girders of bridge decks.

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{WVD}_{z} ((),, t, f) = F_{τ \to f} ({}, K_{z} ((),, t, τ)),

in which F is the Fourier transform and

K_{z} ((),, t, τ) = z ((), t + \frac{true}{τ}) z^{*} ((), t - \frac{true}{τ})

is the signal kernel.…”

Section: Square Time–frequency Distributionsmentioning

confidence: 99%

New damage index based on least squares distance for damage diagnosis in steel girder of bridge's deck

Ahmadi

Anvari

2018

Struct Control Health Monit

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“…For the measurement of viscosity, most people use viscometer, and the measured value is fixed, which has certain limitations. In addition, acoustic emission technology is mainly used for failure process and damage assessment of specimens under compression conditions [31,32]. e parameters of acoustic emission waveform, such as energy, impact times, counting, amplitude, and frequency, are useful for identifying crack characteristics of concrete and masonry materials [33].…”

Section: Introductionmentioning

confidence: 99%

Fracture Characteristics of Polyurethane Grouting Materials Based on Acoustic Emission Monitoring

Ren

Shen

Liu

et al. 2021

Shock and Vibration

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In this study, 16 groups of tests were designed by the orthogonal test method, and a PU grouting material was prepared, which can be used for the construction of sealing wall in mined-out area of coal mine. The basic properties of the material were measured. Firstly, the viscosity of four groups of samples with different polyether polyol contents was measured by a dynamic rheometer. Secondly, the uniaxial compressive strength of pure slurry samples and sand-containing samples was measured by a universal testing machine. Finally, the failure process of sand-containing samples was monitored by acoustic emission equipment. Through the above research and analysis, a PU grouting material with excellent performance has been obtained. That is, when the ratio of polyether triol:polyether tetraol:catalyst:surfactant:chain extender:plasticizer is 11 : 9 : 0.5 : 1.0 : 1.2 : 6.0, PU grouting material has higher injectability and ideal compressive strength, which has been proved in grouting experiments.

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“…In Rao and Subramanyam (2008) the AE signals were analyzed using the wavelet transform. A combined method of Winger-Ville distribution signal processing method with a theoretical velocity dispersion model for AE source location in dispersive media was reported by Kim et al (2013). In Yu et al (2006), a study on the failure detection of composite materials using AE was reported wherein the AE signals were analyzed using Fast Fourier Transform (FFT).…”

Section: Introductionmentioning

confidence: 99%

Grid dispersion and filtering in broadband acoustic emission (AE) source modeling

Raorane¹,

Paćko²

2021

Nauka – Technika – Technologia. Tom 2

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The spatial grid of numerical models of acoustic emission (AE) sources acts as a spatial filter for elastic wave signals. The filtering effects are particularly prominent for short-time, broadband signals -typical for AE. In this paper, we investigate the filtering influence of spatial discretization (meshing) on broadband AE source modeling. The AE source -generating AEs propagating as elastic waves -was modeled using cohesive zone approach, and the numerical simulations were performed in commercial FEM software COMSOL Multiphysics. Results were processed using Fast Fourier Transform, filtered, and subsequently analyzed in terms of the filtering effects of spatial discretization on AE source modeling. In this paper, it is shown that spatial grids in numerical models effectively work like low-pass filters with the cut-off frequency corresponding to the numerical Brillouin zone. The latter induces short wavelength limitation, and the frequency components near (below) the zone edge are amplified in magnitude. It was found that the amplified frequencies represent numerical errors. Also, it was inferred that the filtering effect of spatial discretization can mask the AE source characteristics and affect the quality of the results.

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A combined method of Wigner-Ville distribution with a theoretical model for acoustic emission source location in a dispersive media

Cited by 10 publications

References 21 publications

New damage index based on least squares distance for damage diagnosis in steel girder of bridge's deck

New damage index based on least squares distance for damage diagnosis in steel girder of bridge's deck

Fracture Characteristics of Polyurethane Grouting Materials Based on Acoustic Emission Monitoring

Grid dispersion and filtering in broadband acoustic emission (AE) source modeling

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