Related Experiment Video
Updated: Aug 15, 2026
11:51
Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
Pressure wave propagation in a shaken granular bed
Stephen R Hostler1, Christopher E Brennen
1California Institute of Technology, Pasadena, California 91125, USA. hostler@case.edu
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 26, 2005
Summary
External vibration disrupts force chains in granular materials, altering how pressure waves propagate. This study investigates these effects in a shaken granular bed, revealing impacts on wave characteristics.
Area of Science:
- Physics
- Materials Science
- Geophysics
Background:
- Pressure waves in granular materials transmit via force chains.
- Force chains are fragile and susceptible to disruption by perturbations, including waves and external vibration.
- Disruption of force chains significantly alters wave propagation characteristics.
Purpose of the Study:
- To investigate the effects of external vibration on wave propagation in a shaken granular bed.
- To understand how vibration-induced force chain disruption influences pressure wave transmission.
Main Methods:
- Experimental setup involving a shaken granular bed.
- Generation and measurement of pressure waves.
- Application of controlled external vibration.
Main Results:
- Vibration significantly alters the characteristics of pressure wave propagation.
- Disruption of force chains by vibration leads to changes in wave speed and attenuation.
- The degree of disruption is dependent on vibration parameters.
Conclusions:
- External vibration is a critical factor influencing wave propagation in granular media.
- Understanding these effects is crucial for applications involving granular materials under dynamic conditions.
- Force chain dynamics play a key role in modulating wave behavior in response to external stimuli.
Related Concept Videos
01:04Travelling Waves
A wave is a disturbance that propagates from its source, repeating itself periodically, and is typically associated with simple harmonic motion. Mechanical waves are governed by Newton's laws and require a medium to travel. A medium is a substance in which a mechanical wave propagates, and the medium produces an elastic restoring force when it is deformed.
Water waves, sound waves, and seismic waves are some examples of mechanical waves. For water waves, the wave propagation medium is water;...
Water waves, sound waves, and seismic waves are some examples of mechanical waves. For water waves, the wave propagation medium is water;...
01:17Sound as Pressure Waves
Sound waves, which are longitudinal waves, can be modeled as the displacement amplitude varying as a function of the spatial and temporal coordinates. As a column of the medium is displaced, its successive columns are also displaced. As the successive displacements differ relatively, a pressure difference with the surrounding pressure is created. The gauge pressure varies across the medium.
The pressure fluctuation depends on the difference in displacements between the successive points in the...
The pressure fluctuation depends on the difference in displacements between the successive points in the...
01:07Propagation of Waves
When a wave propagates from one medium to another, part of it may get reflected in the first medium, and part of it may get transmitted to the second medium. In such a case, the interface of the two mediums can be considered as a boundary that is neither fixed nor free.
Consider a scenario where a wave propagates from a string of low linear mass density to a string of high linear mass density. In such a case, the reflected wave is out of phase with respect to the incident wave, however the...
Consider a scenario where a wave propagates from a string of low linear mass density to a string of high linear mass density. In such a case, the reflected wave is out of phase with respect to the incident wave, however the...
01:16Shock Waves
While deriving the Doppler formula for the observed frequency of a sound wave, it is assumed that the speed of sound in the medium is greater than the source's speed through it. When this condition is breached, a shock wave occurs.
When the source's speed approaches the speed of sound, constructive interference between successive wavefronts emitted by the source occurs immediately behind it. Initially, scientists believed that this constructive interference would result in such high pressures...
When the source's speed approaches the speed of sound, constructive interference between successive wavefronts emitted by the source occurs immediately behind it. Initially, scientists believed that this constructive interference would result in such high pressures...
01:17Standing Waves
Sometimes waves do not seem to move; rather, they just vibrate in place. Unmoving waves can be seen on the surface of a glass of milk kept in a refrigerator, which is one example of standing waves. Vibrations from the refrigerator motor create waves on the milk that oscillate up and down but do not seem to move across the surface. These waves are formed or created by the superposition of two or more identical moving waves in opposite directions. The waves move through each other, with their...
01:10Wave Parameters
The simplest mechanical waves are associated with simple harmonic motion and repeat themselves for several cycles. These simple harmonic waves can be modeled using a combination of sine and cosine functions. Consider a simplified surface water wave that moves across the water's surface. Unlike complex ocean waves, in surface water waves, water moves vertically, oscillating up and down, whereas the disturbance of the wave moves horizontally through the medium. If a seagull is floating on the...