Wireless Sensing in Complex Electromagnetic Media: Construction Materials and Structural Monitoring

Date

2015-10-01

Author

Ozbey, Burak
DEMİR, Hilmi Volkan
Kurç, Özgür
ERTÜRK, VAKUR BEHÇET
ALTINTAŞ, AYHAN

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

In this paper, wireless sensing in the presence of complex electromagnetic media created by combinations of reinforcing bars and concrete is investigated. The wireless displacement sensing system, primarily designed for use in structural health monitoring (SHM), is composed of a comb-like nested split-ring resonator (NSRR) probe and a transceiver antenna. Although each complex medium scenario is predicted to have a detrimental effect on sensing in principle, it is demonstrated that the proposed sensor geometry is able to operate fairly well in all scenarios except one. In these scenarios that mimic real-life SHM, it is shown that this sensor exhibits a high displacement resolution of 1 mu m, a good sensitivity of 7 MHz/mm in average, and a high dynamic range extending over 20 mm. For the most disruptive scenario of placing concrete immediately behind NSRR, a solution based on employing a separator behind the probe is proposed to overcome the handicaps introduced by the medium. In order to obtain a one-to-one mapping from the measured frequency shift to the displacement, a numerical fit is proposed and used. The effects of several complex medium scenarios on this fit are discussed. These results indicate that the proposed sensing scheme works well in real-life SHM applications.

Subject Keywords

Wireless passive sensor, Displacement sensor, Strain sensor, Nested split ring resonator (NSRR)

URI

https://hdl.handle.net/11511/33279

Collections

Department of Civil Engineering, Article