In this paper the authors analyze theoretically the wave motion which propagates through a porous media with semiinfinite length, under the assumption that the motion is a shallow surface wave. The relation between frictional loss and average glass ball diameter is obtained as next equation from laboratory test. [numerical formula] where α=H_O^2h/L^2x α=0.008133(h/d^2)+0.2501 β=0.002562(h/d)+0.2861