Building the UPPA High Capacity Tensiometer

Joao Mendes (1) , Domenico Gallipoli (1) , Fabian Boeck , Georg Von Unold , Alessandro Tarantino (2)

1 SIAME - Laboratoire des Sciences de l'Ingénieur Appliquées à la Mécanique et au génie Electrique
2 University of Strathclyde [Glasgow]

High capacity tensiometers (HCTs) are sensors capable of directly measuring tensile pore water pressure (suction) in soils. HCTs are typically composed of a casing that encapsulates a high air entry value ceramic filter, a water reservoir and a pressure sensing element. Since the creation of the first HCT by Ridley and Burland in 1993 at Imperial College London, HCTs have been almost exclusively built and used in academic research. The limited use in industrial applications can be explained by a lack of unsaturated soil mechanics knowledge among engineering practitioners but also by the technical difficulties associated to the direct measurement of tensile water pressures beyond the cavitation limit of -100kPa. In this paper, we present the recent design and manufacture of a new HCT at the Université de Pau et des Pays de l'Adour (UPPA) in France. Different prototypes were tried by changing the main components of the device including the type of ceramic filter, pressure transducer and geometry of the external casing. In particular, two ceramic filters of distinct porosity, three pressure transducers with distinct materials/geometries and four casing designs were tested.

Domains: Physics [physics]

Joao Mendes, Domenico Gallipoli, Fabian Boeck, Georg Von Unold, Alessandro Tarantino. Building the UPPA High Capacity Tensiometer. 3rd European Conference on Unsaturated Soils \textendash ``E-UNSAT 2016'', Sep 2016, Paris, France, France. pp.10001, ⟨10.1051/e3sconf/20160910001⟩. ⟨hal-02154016⟩