DEVICE FOR TENSION FORCE ESTIMATION IN CABLE USING PIEZOELECTRIC ELEMENT AND TENSION FORCE ESTIMATION METHOD THEREOF

摘要

The present invention relates to an apparatus for estimating a cable tension change, which is to monitor a tension change of a cable installed at a bridge and the like, and a field measuring method of cable tension, and more particularly, to a technology for estimating a tension change of a cable through a diaphragm having a preset natural frequency. The apparatus for estimating a cable tension change of the present invention comprises: a piezoelectric element; a diaphragm connected to the piezoelectric element, and having a set natural frequency; and a pair of fixtures provided at both ends of the diaphragm, and fixed to a cable. The piezoelectric element measures a change in the natural frequency of the diaphragm generated when the cable tension is changed. In addition, according to the present invention, the field measuring method of cable tension which estimates cable tension using a piezoelectric element, comprises: a fixing step of fixing a diaphragm connected to a piezoelectric element to a cable; and a calculation step of calculating a tension change of the cable by measuring an impedance response (Z′) corresponding a changed natural frequency (f′) of the diaphragm in accordance with the tension change of the cable. Accordingly, the apparatus of the present invention does not require measurement of the vibration characteristics of the cable varied in accordance with the specifications or tensions that do not require separate equipment such as an exciter, is easily installed, and can reliably monitor tension changes.