A Theory for Predicting Velocities of Soil Particles and Seepage Flow During Upward Seepage Failure

Abstract

This paper presents a theory describing the velocities of soil particles and seepage flow after seepage failures, which have not been understood until now. The theory focuses its target on one-dimensional seepage failures caused by upward seepage flows, whereby the equations of motion of the soil particles and the seepage water are analyzed. Assuming their incompressibility and considering uniform flows, the equations yield the system of ordinary differential equations for their velocities. Herein, the equations are analytically and numerically solved and the approximation of the solutions is discussed with previous experimental results. The results have revealed that the velocities of the soil particles and the seepage water accelerate in proportion to the gravitational acceleration and the increase rate of the pressure gradient and that the difference of the two velocities after the failure is kept slightly greater than the seepage flow velocity at the critical hydraulic gradient.