Lamb wave attenuation in a rough plate. I. Analytical and experimental results in an anisotropic plate

2008 ◽  
Vol 104 (7) ◽  
pp. 074908 ◽  
Author(s):  
Catherine Potel ◽  
Damien Leduc ◽  
Bruno Morvan ◽  
Claude Depollier ◽  
Anne-Christine Hladky-Hennion ◽  
...  
Keyword(s):  
Lamb Wave ◽  
Anisotropic Plate ◽  
Wave Attenuation ◽  
Experimental Results ◽  
Rough Plate

Lamb wave attenuation in a rough plate. II. Analytical and numerical results in a fluid plate

2008 ◽  
Vol 104 (7) ◽  
pp. 074909 ◽  
Author(s):  
Catherine Potel ◽  
Damien Leduc ◽  
Bruno Morvan ◽  
Claude Depollier ◽  
Anne-Christine Hladky-Hennion ◽  
...  
Keyword(s):  
Lamb Wave ◽  
Wave Attenuation ◽  
Numerical Results ◽  
Rough Plate

Study of wave attenuation in concrete

1993 ◽  
Vol 8 (9) ◽  
pp. 2344-2353 ◽  
Author(s):  
J-M. Berthelot ◽  
Souda M. Ben ◽  
J.L. Robert
Keyword(s):  
Experimental Study ◽  
Plane Wave ◽  
Wave Attenuation ◽  
Plane Waves ◽  
Propagation Distance ◽  
Experimental Results ◽  
The Other ◽  
Wave Frequency ◽  
Concrete Composition ◽  
Analytical Expression

The experimental study of wave attenuation in concrete has been achieved in the case of the propagation of plane waves in concrete rods. Different mortars and concretes have been investigated. A transmitter transducer coupled to one of the ends of the concrete rod generates the propagation of a plane wave in the rod. The receiver transducer, similar to the previous one, is coupled to the other end of the rod. The experimental results lead to an analytical expression for wave attenuation as function of the concrete composition, the propagation distance, and the wave frequency.

Experimental verification and validation of nonlocal peridynamic approach for simulating guided Lamb wave propagation and damage interaction

2019 ◽  
Vol 18 (5-6) ◽  
pp. 1789-1802 ◽  
Author(s):  
Subir Patra ◽  
Hossain Ahmed ◽  
Mohammadsadegh Saadatzi ◽  
Sourav Banerjee
Keyword(s):  
Wave Propagation ◽  
Structural Health Monitoring ◽  
Nondestructive Evaluation ◽  
Health Monitoring ◽  
Experimental Verification ◽  
Lamb Wave ◽  
Verification And Validation ◽  
Experimental Results ◽  
Lamb Wave Propagation ◽  
Wave Modes

In this article, experimental verification and validation of a peridynamics-based simulation technique, called peri-elastodynamics, are presented while simulating the guided Lamb wave propagation and wave–damage interaction for ultrasonic nondestructive evaluation and structural health monitoring applications. Peri-elastodynamics is a recently developed elastodynamic computation tool where material particles are assumed to interact with the neighboring particles nonlocally, distributed within an influence zone. First, in this article, peri-elastodynamics was used to simulate the Lamb wave modes and their interactions with the damages in a three-dimensional plate-like structure, while the accuracy and the efficacy of the method were verified using the finite element simulation method (FEM). Next, the peri-elastodynamics results were validated with the experimental results, which showed that the newly developed method is more accurate and computationally cheaper than the FEM to be used for computational nondestructive evaluation and structural health monitoring. Specifically, in this work, peri-elastodynamics was used to accurately simulate the in-plane and out-of-plane symmetric and anti-symmetric guided Lamb wave modes in a pristine plate and was extended to investigate the wave–damage interaction with damage (e.g. a crack) in the plate. Experiments were designed keeping all the simulation parameters consistent. The accuracy of the proposed technique is confirmed by performing error analysis on symmetric and anti-symmetric Lamb wave modes compared to the experimental results for pristine and damaged plates.

scholarly journals Integrated Structural Health Assessment Using Piezoelectric Active Sensors

2005 ◽  
Vol 12 (6) ◽  
pp. 389-405 ◽  
Author(s):  
Jeannette R. Wait ◽  
Gyuhae Park ◽  
Charles R. Farrar
Keyword(s):  
Lamb Wave ◽  
Structural Damage ◽  
Structural Integrity ◽  
Damage Identification ◽  
Wave Attenuation ◽  
Health Assessment ◽  
Mechanical Impedance ◽  
Integrated Approach ◽  
Impedance Method ◽  
Sensing Technology

This paper illustrates an integrated approach for identifying structural damage. The method presented utilizes piezoelectric (PZT) materials to actuate/sense the dynamic response of the structures. Two damage identification techniques are integrated in this study, including impedance methods and Lamb wave propagations. The impedance method monitors the variations in structural mechanical impedance, which is coupled with the electrical impedance of the PZT patch. In Lamb wave propagations, one PZT patch acting as an actuator launches an elastic wave through the structure, and responses are measured by an array of PZT sensors. The changes in both wave attenuation and reflection are used to detect and locate the damage. Both the Lamb wave and impedance methods operate in high frequency ranges at which there are measurable changes in structural responses even for incipient damage such as small cracks, debonding, or loose connections. The combination of the local impedance method with the wave propagation based approach allows a better characterization of the system’s structural integrity. The paper concludes with experimental results to demonstrate the feasibility of this integrated active sensing technology.

A direct comparison between vibrational resonance and pulse transmission data for assessment of seismic attenuation in rock

Geophysics ◽  
1990 ◽  
Vol 55 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Dane P. Blair
Keyword(s):  
Elastic Scattering ◽  
Wave Attenuation ◽  
Seismic Attenuation ◽  
Experimental Results ◽  
P Wave ◽  
Whole Body ◽  
Frequency Range ◽  
Vibrational Resonance ◽  
Fine Grained ◽  
Pulse Transmission

For the same volume of rock, I compare the attenuation obtained by seismic pulse transmission over the frequency range 1–150 kHz with that obtained by vibrational resonance techniques over the frequency range 1–50 kHz. The initial studies were performed on a rectangular block of medium‐grained granite which was large enough to permit the installation of a seismic pulse transmission array over a 1.8 m path length, yet small enough to permit whole‐body resonance. A Q of 82, for the P wave, was derived from the vibrational resonance results, whereas a Q of 15 was derived from the pulse transmission results. In light of models proposed for the viscoelastic, geometric, and elastic scattering attenuation mechanisms, the experimental results suggest that this large discrepancy in Q values is due to elastic scattering by grain clusters (rather than individual grains) within the granite. Scattering is significant in the high‐frequency pulse transmission tests, but is considered insignificant in the lower frequency resonance tests. Furthermore, this scattering is represented approximately by a constant-Q loss mechanism, which makes it difficult to separate unambiguously elastic scattering and viscoelastic losses. Subsequent studies performed on a large block of fine‐grained norite yield a resonance Q of 89 and a pulse Q of approximately 102 and suggest a negligible scattering loss for this material. The experimental results for the norite imply that the constant-Q theory of seismic pulse attenuation provides a reasonable description of wave attenuation in a dry, fine‐grained crystalline rock over the frequency range 1–150 kHz.

Damage Detection Using Cointegration Technique and Wavelet Analysis of the Post-Cointegrated Lamb Waves

2013 ◽  
Vol 569-570 ◽  
pp. 908-915
Author(s):  
Phong B. Dao ◽  
Wieslaw Jerzy Staszewski
Keyword(s):  
Time Series ◽  
Wavelet Analysis ◽  
Damage Detection ◽  
Temperature Effect ◽  
Lamb Wave ◽  
Lamb Waves ◽  
Experimental Results ◽  
Temperature Variations ◽  
Multi Level ◽  
Stationary Behaviour

This paper presents an application of Lamb-wave-based damage detection under varying temperature conditions. The method used is based on the cointegration technique and wavelet analysis that are partially built on the analysis of non-stationary behaviour and multi-resolution decomposition of time series, respectively. Instead of directly using Lamb wave data for damage detection, two approaches are used: (1) analysis of cointegrating residuals obtained from the cointegration process of Lamb wave responses and (2) analysis of stationary characteristics of the multi-level wavelet decomposed cointegrating residuals. These two approaches are tested on undamaged and damaged aluminium plates exposed to temperature variations. The experimental results show that the method can isolate damage-sensitive features from the temperature effect and reliably detect damage.

scholarly journals THE EFFECT OF ARTIFICIAL SEAWEED IN PROMOTING THE BUILD-UP OF BEACHES

1968 ◽  
Vol 1 (11) ◽  
pp. 36 ◽  
Author(s):  
W.A. Price ◽  
K.W. Tomlinson ◽  
J.N. Hunt
Keyword(s):  
Wave Propagation ◽  
Mass Transport ◽  
Gravity Waves ◽  
Hydrodynamic Model ◽  
Wave Attenuation ◽  
Field Trials ◽  
Experimental Results ◽  
Wave Tank ◽  
Bed Material

The paper describes tests carried out m the laboratory and in the field in an attempt to discover whether a field of artificial seaweed placed offshore can promote an onshore transport of bed material and hence a build-up of beach levels. Tests in a wave tank showed that beach levels could be built up in this way - the effect of the seaweed being to increase the net drift of bed water m the direction of wave propagation i.e. towards the shore. The field trials were not as conclusive as was hoped, but nevertheless some build-up of beach levels did take place at a time when erosion of the beach due to many storms might have been anticipated. A simple hydrodynamic model is proposed to represent the effect of artificial seaweed on gravity waves. The model predicts increased wave attenuation and increased shoreward mass-transport consistent with the experimental results.

Characterization of Lamb wave attenuation mechanisms

2013 ◽  
Author(s):  
Daniel Schmidt ◽  
Hossein Sadri ◽  
Artur Szewieczek ◽  
Michael Sinapius ◽  
Peter Wierach ◽  
...  
Keyword(s):  
Lamb Wave ◽  
Wave Attenuation
Sign in / Sign up

Export Citation Format

Share Document