BEM ANALYSIS OF LAMB WAVE SCATTERING BY LAYERED PLATE DEBONDING

Since stringers are often applied in engineering constructions to improve thin-walled structures’ strength, methods for damage detection at the joints between the stringer and the thin-walled structure are necessary. A 2D mathematical model was employed to simulate Lamb wave excitation and sensing via rectangular piezoelectric-wafer active transducers mounted on the surface of an elastic plate with rectangular surface-bonded obstacles (stiffeners) with interface defects. The results of a 2D simulation using the finite element method and the semi-analytical hybrid approach were validated experimentally using laser Doppler vibrometry for fully bonded and semi-debonded rectangular obstacles. A numerical analysis of fundamental Lamb wave scattering via rectangular stiffeners in different bonding states is presented. Two kinds of interfacial defects between the stiffener and the plate are considered: the partial degradation of the adhesive at the interface and an open crack. Damage indices calculated using the data obtained from a sensor are analyzed numerically. The choice of an input impulse function applied at the piezoelectric actuator is discussed from the perspective of the development of guided-wave-based structural health monitoring techniques for damage detection.

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Finite element simulation of Lamb wave scattering at delamination damage in composite laminates

The Journal of the Acoustical Society of America ◽

10.1121/1.4709227 ◽

2012 ◽

Vol 131 (4) ◽

pp. 3500-3500

Author(s):

Haiyan Zhang

Keyword(s):

Finite Element ◽

Finite Element Simulation ◽

Lamb Wave ◽

Composite Laminates ◽

Wave Scattering ◽

Element Simulation ◽

Delamination Damage

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Boundary element analysis of Lamb wave scattering by a through-thickness crack in a plate

10.1063/5.0034051 ◽

2020 ◽

Author(s):

Jun Li ◽

Zahra Sharif Khodaei ◽

M. H. Aliabadi

Keyword(s):

Boundary Element ◽

Lamb Wave ◽

Wave Scattering ◽

Element Analysis ◽

Boundary Element Analysis

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Prediction and Measurement of Lamb Wave from Debondings at Structural Features in Composite Laminates

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.558.139 ◽

2013 ◽

Vol 558 ◽

pp. 139-148 ◽

Cited By ~ 2

Author(s):

Ching Tai Ng ◽

Martin Veidt

Keyword(s):

Lamb Wave ◽

Composite Laminates ◽

Wave Scattering ◽

Three Dimensional ◽

Scattered Wave ◽

Structural Features ◽

Complex Structures ◽

Detection Techniques ◽

Fe Simulations ◽

Good Agreement

The interaction of the fundamental anti-symmetric Lamb wave (A0) with debondings at structural features is investigated using experimental data and finite element (FE) simulations. In this study explicit three-dimensional (3D) FE simulations are employed, which allows the study of the scattered wave along different propagation directions. Good agreement between the FE predictions and the measurements are obtained that demonstrates that the 3D FE scattering model is able to accurately predict the Lamb wave scattering characteristics at debondings. The study show that the characteristics of Lamb wave reflected from the debondings at the structure feature is much more complicated than that from defects in flat composite laminates. Parameter studies show that the backward and forward scattering coefficient of Lamb wave is a function of debonding size to wavelength ratio and debonding location. This shows the potential of employing Lamb wave to identify the size and monitor the growth of the debondings. The findings of the study provide improved physical insights into the scattering phenomena, which are important to further advance damage detection techniques for complex structures made by composite laminates.

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On Accuracy of Analytical Modeling of Lamb Wave Scattering at Delaminations in Multilayered Isotropic Plates

International Journal of Structural Stability and Dynamics ◽

10.1142/s0219455415400106 ◽

2015 ◽

Vol 15 (08) ◽

pp. 1540010 ◽

Cited By ~ 19

Author(s):

C. T. Ng

Keyword(s):

Analytical Solutions ◽

Lamb Wave ◽

Wave Scattering ◽

Plate Theory ◽

Analytical Models ◽

Mindlin Plate ◽

Bending Rigidity ◽

Scattering Problems ◽

Explicit Finite Element ◽

Isotropic Plates

The study investigates the accuracy of analytical solutions to the fundamental anti-symmetric Lamb wave scattering at delamination in multilayered isotropic plates. The analytical models are based on the wave function expansion method and Born approximation within the framework of Mindlin plate theory. The study validates the accuracy of modeling the delamination as an inhomogeneity with reduced bending rigidity in predicting Lamb wave scattering induced by geometry change at the delaminated region. A good agreement is observed between the analytical solutions and results of experimentally verified 3D explicit finite element (FE) simulations. The findings support the inhomogeneity assumption in Lamb wave scattering problems and show the feasibility of employing it in delamination characterization.

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