DEFORMATION AND FLUID-FLOW DUE TO A SOURCE IN A PORE-ELASTIC LAYER

The flow of fluid from a point source or sink at some arbitrary height in a layer of deformable porous material is considered. This problem is applicable to filtration through beds of sand and flow in soils. Th e porous material is assumed to be an isotropic, homogeneous, linear e lastic solid. The equations governing the behavior of the medium and f luid are derived for an axisymmetric geometry using linear poro-elasti city theory and are solved using the Hankel transform with the Hankel inversion integral evaluated numerically. The upper surface is stress free and permeable, with the lower surface impermeable to fluid flow. Two different boundary conditions are applied to the lower surface; st ress free and tethered. Results are given for the pressure contours, s urface fluid velocity and the displacement of the solid matrix for a v ariety of source heights and boundary conditions. These results provid e an indication of the amount of swelling of the medium and subsequent deformation of the free surface as a function of the location of the point source and boundary conditions. (C) 1997 by Elsevier Science Inc .