Porosity dependence of sound speed

Author :Theodore F. Argo IV, Matthew D. Guild, and Preston S. Wilson, Matthias Schröter,Charles Radin, and Harry L. Swinney
Publication :J. Acoustical Society of America
Volume :129
Pages :EL101-EL106
Year :2011

Sound propagation in water-saturated granular sediments is known to depend on the sediment porosity, but few data in the literature address both the fre- quency and porosity dependency. To begin to address this deficiency, a flu- idized bed technique was used to control the porosity of an artificial sediment composed of glass spheres of 265 ?m-diameter. Time-of-flight measurements and the Fourier phase technique were utilized to determine the sound speed for frequencies from 300 kHz to 800 kHz, and porosities from 0.37 to 0.43. A Biot-based model qualitatively describes the porosity dependence.