Continuous coaxial cable sensors for monitoring of RC structures with electrical time domain reflectometry

Genda Chen*, Huimin Mu, David Pommerenke, James L. Drewniak

*Corresponding author for this work

Research output: Contribution to journalConference articlepeer-review


This study was aimed at developing and validating a new type of coaxial cable sensors that can be used to detect cracks or measure strains in reinforced concrete (RC) structures. The new sensors were designed based on the change in outer conductor configuration under strain effects in contrast to the geometry-based design in conventional coaxial cable sensors. Both numerical simulations and calibration tests with strain gauges of a specific design of the proposed cables were conducted to study the cables' sensitivity. Four designs of the proposed type of sensors were then respectively mounted near the surface of six 3-foot-long RC beams. They were tested in bending to further validate the cables' sensitivity in concrete members. The calibration test results generally agree with the numerical simulations. They showed that the proposed sensors are over 10∼50 times more sensitive than conventional cable sensors. The test results of the beams not only validate the sensitivity of the new sensors but also indicate a good correlation with the measured crack width.

Original languageEnglish
Pages (from-to)410-421
Number of pages12
JournalProceedings of SPIE - The International Society for Optical Engineering
Publication statusPublished - 26 Nov 2003
Externally publishedYes
EventSmart Structures and Materials 2003: Smart Systems and Nondestructive Evaluation for Civil Infrastructures - San Diego, CA, United States
Duration: 3 Mar 20036 Mar 2003


  • Coaxial cables
  • Continuous sensors
  • Crack sensors
  • Electrical time domain reflectometry
  • Reflection coefficient
  • Strain sensors

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

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