CHEN Wei-yun, XIA Tang-dai, CHEN Wei, ZHAI Chao-jiao. Propagation of Plane P-Waves at the Interface Between an Elastic Solid and an Unsaturated Poroelastic Medium[J]. Applied Mathematics and Mechanics, 2012, 33(7): 781-795. doi: 10.3879/j.issn.1000-0887.2012.07.001
 Citation: CHEN Wei-yun, XIA Tang-dai, CHEN Wei, ZHAI Chao-jiao. Propagation of Plane P-Waves at the Interface Between an Elastic Solid and an Unsaturated Poroelastic Medium[J]. Applied Mathematics and Mechanics, 2012, 33(7): 781-795.

# Propagation of Plane P-Waves at the Interface Between an Elastic Solid and an Unsaturated Poroelastic Medium

##### doi: 10.3879/j.issn.1000-0887.2012.07.001
• Rev Recd Date: 2012-04-11
• Publish Date: 2012-07-15
• A linear viscoporoelastic model was developed to describe the problem of reflection and transmission of an obliquely incident plane Pwave at an interface between an elastic solid and an unsaturated poroelastic medium in which the solid matrix was filled with two weakly coupled fluids (liquid and gas). The expressions for the amplitude reflection coefficients and amplitude transmission coefficients were derived using the potential method. The present derivation was subsequently applied to study the energy conversions among the incident, reflected and transmitted wave modes. It was found that the reflection coefficients and transmission coefficients in the forms of amplitude ratios and energy ratios are functions of incident angle, liquid saturation, frequency of incident wave and elastic constants of the upper and lower media. The numerical computations are performed graphically, and the effects of the incident angle, frequency and liquid saturation on the amplitude and energy reflection and transmission coefficients are respectively discussed. It was verified that during transmission process there was no energy dissipation at the interface.
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