ABSTRACT
From 1994, a triaxial device (USP) has been developed at the University of Napoli Federico II in order to test soils under unsaturated conditions (Rampino et al. 1999). In the original version of this cell, a modified version of a Bishop & Wesley (1975) apparatus and the axis-translation technique (Hilf 1956) were used, with pore-air and pore-water pressures controlled at the top and bottom of the sample, respectively. The USP device has been used during several testing campaigns to date, for example Aversa & Nicotera (1999), Bilotta et al. (2005), Vassallo et al. (2007), Casini et al. (2007), Cattoni et al. (2007) and Papa et al. (2008). A new design of the apparatus is proposed in this paper including modifications introduced to reduce testing time. Also discussed are the experimental procedures adopted during the tests and some preliminary results obtained on a moist compacted pyroclastic silty sand.
2 TRIAXIAL APPARATUSES
