On-line Structural Damage Localization and Quantification Using Wireless Sensors

On-line Structural Damage Localization and Quantification Using Wireless Sensors

In this paper, a wireless sensing system was designed to realize on-line damage localization and quantification of a structure using the frequency response function change method(FRFCM). Data interrogation algorithms were embedded in the computational core of the wireless sensing units to extract necessary structural features, i.e. the frequency spectrum segments around eigenfrequencies, automatically from measured structural response for the FRFCM. Instead of the raw time history of the structural response, the extracted compact structural features were transmitted to the host computer. As a result, with less data transmitted between the wireless sensors and host computer, the energy consumed by the wireless transmission was reduced. To validate the performance of the proposed wireless sensing system, a six-storey steel building with replaceable bracings in each story was instrumented with the wireless sensors for on-line damage detection during shaking table tests. The accuracy of the wireless sensing system employed was verified by comparison of data recorded using a traditional wired monitoring system. The results demonstrate that by taking advantage of collocated computing resources in wireless sensors, the proposed wireless sensing system can locate and quantify damage with acceptable accuracy and high energy efficiency.