Volume 26, Issue 1 (March 2003)
Interfacial Behavior of Unsaturated Soil with Small-scale Models and Use of Image Processing Techniques
Two small-scale prototypes (physical models) intended to study soil behavior are presented. They allow for 1D and 2D tests on unsaturated soil in a wide range of hydraulic and mechanical boundary conditions. The instrumentation of the testing facilities designed to measure pore water pressures, water fluxes, top displacements, and in-plane displacement fields are detailed. Special attention is devoted to boundary conditions: effects of friction and cohesion at the interface between soil and model on the experimental results and ways to limit their effects are presented. Furthermore, the image processing techniques used to measure in-plane displacements are reviewed. A simple and accurate method based on white light speckle autocorrelation and a marked membrane is proposed.