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Updated: Jun 21, 2026
06:07
Studying Large Amplitude Oscillatory Shear Response of Soft Materials
Published on: April 25, 2019
Nonlinear effects for coda-type elastic waves in stressed granular media
1LAUM, CNRS, Université du Maine, Avenue O. Messiaen, 72085 Le Mans, France. vincent.tournat@univ-lemans.fr
Summary
Acoustic waves can alter the elastic properties of granular materials, even at low amplitudes. Coda signal analysis effectively monitors these changes in unconsolidated granular structures.
Area of Science:
- Physics
- Materials Science
- Acoustics
Background:
- Nonlinear acoustic effects in granular media are crucial for understanding material behavior.
- Scattering and nonlinear elastic phenomena significantly distort acoustic wave signals.
Purpose of the Study:
- To investigate the nonlinear acoustic effects of multiple scattered elastic waves in granular media.
- To demonstrate how low-amplitude acoustic waves can modify the elastic properties of granular matter.
- To highlight the utility of coda signal analysis for monitoring granular material properties.
Main Methods:
- Transmission of short wave packets above the cutoff frequency through a stressed granular medium (glass beads).
- Reception and analysis of distorted signals, accounting for multiple scattering and nonlinear effects.
- Application of coda signal analysis for time-resolved monitoring of elastic response.
Main Results:
- Acoustic waves, even with low deformation amplitudes, were observed to modify the medium's elastic properties.
- Signal distortion was significant due to both nonlinearity and multiple scattering.
- Coda signal analysis proved effective in tracking subtle modifications in the granular structure's elastic response.
Conclusions:
- Acoustic wave interactions in granular media exhibit significant nonlinear and scattering effects.
- Understanding these effects is vital for nondestructive testing of granular materials.
- Coda signal analysis is a powerful tool for real-time characterization of granular media elasticity.
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