Steel Reinforcement Corrosion Detection with Coaxial Cable Sensors

Abstract

Corrosion processes in the steel reinforced structures can result in structural deficiency and with time create a threat to human lives. Millions of dollars are lost each year because of corrosion. According to the U. S. Federal Highway Administration (FHWA) the average annual cost of corrosion in the infrastructure sector by the end of 2002 was estimated to be $22.6 billion. Timely remediation/retrofit and effective maintenance can extend the structure's live span for much less expense. Thus the considerable effort should be done to deploy corrosion monitoring techniques to have realistic information on the location and the severity of damage. Nowadays commercially available techniques for corrosion monitoring require costly equipment and certain interpretational skills. In addition, none of them is designed for the real time quality assessment. In this study the crack sensor developed at Missouri University of Science and Technology is proposed as a distributed sensor for real time corrosion monitoring. Implementation of this technology may ease the pressure on the bridge owners restrained with the federal budget by allowing the timely remediation with the minimal financial and labor expenses. The sensor is instrumented in such a way that the location of any discontinuity developed along its length can be easily detected. When the sensor is placed in immediate vicinity to the steel reinforcement it is subjected to the same chemical process as the steel reinforcement. And corrosion pitting is expected to develop on the sensor exactly at the same location as in the rebar. Thus it is expected to be an effective tool for active corrosion zones detection within reinforced concrete (RC) members. A series of laboratory tests were conducted to validate the effectiveness of the proposed methodology. Nine sensors were manufactured and placed in the artificially created corrosive environment and observed over the time. To induce accelerated corrosion 3% and 5% NaCL solutions were used. Based on the test results, the proposed/corrosion distributed sensor is capable of delivering fairly accurate information on the location of a discontinuity along the sensor caused by corrosion pitting. Forensic study was also conducted to validate the concept. In order to test the sensors in real live condition, 27 sensors were prepared to be placed into RC beams. The beams will be subjected to corrosive environment. After that the sensors will be monitored over the time for signs of corrosion.

Meeting Name

Sensors and Smart Structures Technologies for Civil, Mechanical, and Aerospace Systems (2011: Mar. 7-10, San Diego, CA)

Department(s)

Electrical and Computer Engineering

Second Department

Civil, Architectural and Environmental Engineering

Keywords and Phrases

Accelerated Corrosion; Annual Cost; Chemical Process; Coaxial Cable Sensors; Corrosion Monitoring; Corrosion Pitting; Corrosion Process; Corrosion Sensor; Corrosion Zone; Corrosive Environment; Crack Sensors; Distributed Sensor; Effective Tool; Federal Budget; Federal Highway Administration; Human Lives; Infrastructure Sector; Labor Expense; Laboratory Test; Missouris; NaCl Solution; RC Beams; Real Time Corrosion Monitoring; Real-Time Quality; Science And Technology; Steel Reinforcements; Test Results; Land Fill; Waste Disposal

International Standard Book Number (ISBN)

978-0819485434

International Standard Serial Number (ISSN)

0277-786X

Document Type

Article - Conference proceedings

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2011 SPIE, All rights reserved.

Publication Date

01 Mar 2011

Link to Full Text

Share

 
COinS