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1. INTRODUCTION
1.1 Theory of Operation
The Geokon Vibrating Wire Strandmeter is designed to measure change in deformation in wire
strands such as those that are commonly used in tiebacks and earth anchors.
The instrument consists of a vibrating wire sensing element in series with a heat treated, stress
relieved spring which is connected to the wire at one end and a connecting rod at the other. The
unit is fully sealed and operates at pressures of up to 250 psi. As the connecting rod is pulled out
from the gage body, the spring is elongated causing an increase in tension, which is sensed by
the vibrating wire element. The tension in the wire is directly proportional to the extension;
hence, the change in deformation can be determined very accurately by measuring the strain
change with the vibrating wire readout box.
Figure 1 - Model 4410 Vibrating Wire Strandmeter