Acoustic scattering by buried objects in a rigid porous material

Land mines buried a few inches below the surface of the ground can be found by acoustic excitation of the porous ground surface and measuring the particle velocity at the surface. There are various theoretical models describing the ground: from a rigid porous frame model to a compete layered poroelastic description. The goal of this paper is to use the approach of Berry et al. to calculate the acoustic field at points on the ground surface in the vicinity of an object buried in a rigid, porous soil. The excitation is point sound source placed in the air above the ground, which is modeled a rigid, porous frame. A boundary element method is used for numerical integration to calculate the scattered acoustic field due to the presence of the object. This study represents the first step towards developing a complete model of acoustic scattering from near-surface objects embedded in a layered poroelastic material. The predicted disturbance associated with the buried object is much smaller than observed in field measurements.