Assessement of soil-water interaction characteristics using wave-based techniques

Abstract

Soils are particulate and multi-phase materials(i.e., air, fluid, solid), therefore, their properies capture the interation among distinct phases. The negative pore-water pressure in menisci at particle contacts increases the interparticle forces, changes the small-strain stiffness, and alters all forms of conduction and diffusion processes in unsaturated particulate materials. It has been difficult in evaluation such effects in common geotechnical engineering practices. A drying cell is newly developed to assess the characteristics of unsaturated particulate materials with the aid of elastic and electrmagnetic waves. Bender elements(i.e., bimorphs) are installed into two metal caps of the drying cell, which act as electrodes. This configuration allows acquiring elastic and electromagnetic properties simultaneously. Continuous drying tests are performed on laboratory specimens made of three different soils. Overall, experimental test results suggest that soil-water interaction can be effectively assessed using the developed cell with the aid of elastic and electromagnetic waves.