Geosense VWS-2000 Surface Mount Strain Gauges

Geosense VWS-2000 series vibrating wire surface mount strain gauges are designed for the long term monitoring of steel or concrete structures. Gauges may be attached to steel structures by arc welding or, using alternative end blocks, bonded or grouted into concrete.

The strain gauge operates on the principle that a tensioned wire, when plucked, vibrates at its resonant frequency. The square of this frequency is proportional to the strain in the wire.

The gauge consists of two end blocks with a tensioned steel wire between them. The end blocks can be attached to steel or concrete by arc welding, bonding or with groutable anchors.

Around the wire is a magnetic coil which, when pulsed by a vibrating readout or data logger interface, plucks the wire and measures the resultant resonant frequency of vibration.

As the steel or concrete surface undergoes strain, the end blocks will move relative to each other. The tension in the wire between the blocks will change accordingly, thus altering the resonant frequency of the wire.

VWS-2000 vibrating wire strain gauges may be read by the VW-2106 or any vibrating wire readout device and may be readily data logged using the Campbell Scientific CR-series, Cautus Geo’s Cautus Logger CL1 or any other data loggers with vibrating wire interface modules.

VWS-2000 gauges are suitable for long term continuous excitation, thus allowing for continuous low frequency dynamic readings, which is applicable to the display of loads in weighing systems for trucks or investigations into bridge loads.

Vibrating wire strain gauges output a frequency signal and are therefore insensitive to resistance changes in connecting cables caused by contact resistance or leakage to ground.

Cable may be readily and simply extended on site without special precautions. Gauges may be read up to 1000 meters away from their installed location without change in calibration.