Development of a commercial tensiometer for triaxial testing of unsaturated soils

Abstract

A new suction probe, the WF-DU tensiometer, has been developed by Wykeham Farrance in collaboration with Durham University. The performance of the new suction probe is assessed in terms of the minimum negative value of pressure that can be measured by the probe before cavitation. A series of tests performed on four different units of the same design of tensiometer is presented and the results are discussed in relation to the procedure adopted for the saturation of the probe prior to the tests. Other aspects of the tensiometer response are interpreted by making reference to similar experiments published in the literature. All tensiometers used in this work are calibrated in the positive range of pressure. The extrapolation of such calibration to the domain of negative pressures is validated by using the tensiometer to measure known values of suction. Copyright ASCE 2006.