The Vibrating Wire Soil Extensometer monitors lateral and longitudinal deformation of soil and different types of embankments and embankment dams.
The instrument consists of a vibrating wire displacement sensor encased in a sealed body. The body contains a telescopic outer PVC pipe fitted with two flanges and an inner stainless steel rod. One end of the rod is attached to the flange, while its other end is connected to a displacement sensor attached to the other flange.
As deformation occurs, the telescopic pipe moves with the soil causing the rod to operate the displacement sensor. Displacement is measured by portable readout unit or a data logger. The initial reading of the instrument is used as a datum. Subsequent readings are compared to the datum to calculate the magnitude, rate, and acceleration of movement.
The standard length of the instrument is 1m, and it can be extended to accommodate project requirements. The flexible design allows implementation of different configurations with various stroke and gauge lengths. The instrument can be chained together in series to monitor the incremental deformation across the structure to be monitored.
- Gauge length: 1 m
- Extension kits: 0.5, 1, 2 & 3m
- Sensor range: 25, 50, 75, 100, 150 mm
- Accuracy: ±0.10% FS
- Resolution: 0.025% FS
- Non-linearity: <0.5% FS
- Operating temperature: -20 to +80°C
- Instrument body: 28 mm
- Flange diameter: 280 mm
