Interfels' vibrating wire piezometers are designed for accurate measurement of pore water pressures in fully or partially saturated soil and rock.  This is particularly useful in estimating slope stability, safe placement rate of fill or excavation, design and build for lateral or uplift pressures or buoyancy, monitoring the performance of earth-fill dams and embankments, seepage and verify models of flow, monitor surface water run-off,  water levels at contaminated sites etc.

The borehole version is a general-purpose piezometer is equipped with a sintered stainless steel filter.

The embankment version is equipped with high or low - air entry ceramic filters.

The push-In version (sintered stainless steel filter) threads onto M28x1.5mm drill pipe or CPT rods.

With over 30 years experience in Vibrating Wire technology, the Interfles' sensors are robust, have excellent long term stability and can be used with long cable lengths without any signal degradation.

The piezometers comprise a porous filter tip element integral with a diaphragm type vibrating wire pressure transducer. A cable connects the transducer to a read-out, terminal unit or data-logger. The piezometers work on the vibrating wire principle whereby a tensioned wire is attached to a diaphragm, water or pore fluid pressure acts on one side of the diaphragm changing the tension in the wire. A direct relationship exists between the pressure on the diaphragm and the tension in the wire. Plucking or sweeping via an electromagnetic coil excites the wire and the resulting resonant frequency of vibration is picked up by the same coil.  The data is then recorded and converted to engineering units using a read-out unit or a logger.