Selective wave transmission in strongly nonlinear disordered granular chains

Area of Science:

• Physics
• Materials Science
• Geophysics

Background:

• Granular materials exhibit complex wave propagation behaviors.
• Understanding disorder effects is crucial for geophysical applications.

Purpose of the Study:

• To numerically investigate wave propagation in disordered granular chains.
• To model selective transmission and attenuation in random granular media.

Main Methods:

• Numerical simulations of 1000-granule chains with normally distributed radii.
• Analysis of responses to striker impact and band-limited white-noise excitation.
• Characterization of momentum propagation and transfer functions.

Main Results:

• A critical disorder level (σc ≈ 0.1) separates weak and strong regimes for striker impacts.
• Universal power-law decay (∝k⁻⁰.⁸³) observed for momentum at long distances.
• Disorder induces broadband mechanical noise suppression and reveals narrow transmission passbands.

Conclusions:

• Disordered granular chains serve as minimal models for wave phenomena in granular media.
• Findings align with experimental observations in soils, relevant for geophysical studies.
• The study provides insights into near-surface characterization and buried-object detection.