An experimental platform for measuring soil water characteristic curve under transient flow conditions

Abstract

Soil Water Characteristic Curve (SWCC) is the core of unsaturated soil mechanics. The accuracy of modeling unsaturated soil seepage and consolidation behavior are highly governed by SWCC. The conventional testing methods only measured two state variables under the equilibrium condition. Those investigations were usually conducted on a Representative Elementary Volume (REV) scale less than the full length of suction/moisture profile of sandy soil. To further investigate both point-wise and the global SWCC measurement under transient flow condition, a dynamic SWCC testing platform is set up in The University of Queensland. This experimental platform integrates Spatial Time Domain Reflectometry (Spatial TDR) technique, tensiometers and outflow logging by electrical bench scales, so that the consistent logging of moisture profile, suction profile and in/outflow can be achieved. In this study, the experimental platform is briefly presented with some preliminary outcomes and the potential problems of setup are discussed.