Promising results have been shown in recent studies using commercial coaxial ETDR sensing cables for health monitoring application of concrete beam structures subject to bending load. Although distributed strain monitoring and crack damage detection capabilities of the sensors were demonstrated, the low signal-to-noise ratio of the sensors smears the details of the strain measurement that the ETDR signal waveform can convey. A high-sensitivity coaxial sensor prototype specifically designed for distributed strain sensing application has been recently developed in-house. It has been shown that the prototype sensor has a much superior sensitivity in terms of ETDR signal response to applied loads than commercial coaxial cable counterpart. In this paper, the effectiveness of using an embedded high-sensitivity coaxial sensor prototype to monitor transverse shear response of a concrete cylinder is investigated. Both single and double plane transverse shear tests were conducted. The test results show that the embedded high-sensitivity ETDR prototype sensor is capable of detecting the on-set as well as monitoring the growth of shear-induced crack damages in concrete cylinder specimens.

Date Published: 20 April 2000
PDF: 10 pages
Proc. SPIE 3988, Smart Structures and Materials 2000: Smart Systems for Bridges, Structures, and Highways, (20 April 2000); doi: 10.1117/12.383153

Published in SPIE Proceedings Vol. 3988:
Smart Structures and Materials 2000: Smart Systems for Bridges, Structures, and Highways
S.-C. Liu, Editor(s)