Hydraulic Characterization of Porous Materials Using a Rainfall Simulator to Model Flows in Natural and Artificial Non-Saturated Materials

Abstract

Cumulative runoff curves are created by applying constant rainfall of known intensity using a rain simulator. These curves allow us to determine, with good accuracy, the initial loss, the initial time of runoff, and the constant loss. The approach is to model infiltration in an unsaturated medium using a draining reservoir paradigm. Simulated rainfall is applied to a typical soil considered to be composed of two superimposed layers of different permeabilities. This approach enables us to represent the drainage porosity as a function of the constant loss and the initial runoff time, which are measured during the rain simulation. Thus it is possible to calculate the infiltrated volumes, the initial runoff times, and the runoff volumes which are induced by rains of different intensities.Four case studies are used to illustrate the application of our approach.