VW Soil Extensometer GEO-XS
The GEO-XS VW Soil Extensometer monitors lateral and longitudinal deformation of soil and different types of embankments and embankment dams.
It comprises a displacement transducer connected to an extension rod and fixed between a pair of anchor beams.
The assembly is housed in and protected by an external telescopic sleeve. To form a ‘Chain Extensometer’, Soil Extensometers are linked together, in series, using the anchor beams as connectors.
The internal sensing element is housed within an outer PVC sleeve which is sealed by O-rings at each end. The sleeve, with telescopic sections with O- ring seals, is extended along the whole length of the rod to the next anchor.
As structural movement occurs, the rod is moved within the housing. The shaft movement changes the tension in the sensor spring which, in turn, changes the tension in the Vibrating Wire.
Different combinations of anchor spacing (Gauge Length) and sensor range can we used to provide an optimum sensing accuracy and range. i.e. for maximum strain resolution, a shorter transducer length will provide the best results. For maximum deformation, use a longer transducer or a shorter gauge length.