Corrosion of embedded reinforcement is the leading form of deterioration affecting the integrity of reinforced and prestressed concrete bridges around the world. If undetected, corrosion can reduce the service life of a bridge and lead to expensive repairs. The research team at the University of Texas at Austin has developed a new class of passive wireless corrosion sensor. The sensor platform provides an economical and nondestructive means of detecting the initiation of corrosion within concrete.
The sensor is powered in a wireless manner through inductive coupling to an external reader that can be handheld or mounted on a vehicle. It is envisioned that the low-cost sensor will be embedded in concrete during construction and interrogated intermittently over the service life of the bridge. The sensor output is expected to enhance the quality of information that is routinely collected during federally mandated bridge inspections.
The prototype sensor consists of a resonant circuit that is inductively coupled to a sacrificial transducer. Corrosion of the sacrificial element alters the measured sensor response and these changes are used to detect corrosion of the embedded reinforcement. Long-term exposure tests were used to evaluate the reliability of the passive sensors.
Sensors were embedded in reinforced concrete specimens and successfully detected the onset of corrosion in the adjacent reinforcement. Unlike the traditional corrosion evaluation methods, such as half-cell potentials, the sensor output is not sensitive to variations in temperature and moisture content of the concrete.
Sharon L. Wood is the Dean of the Cockrell School of Engineering and holds the Cockrell Family Chair in Engineering #14 at the University of Texas at Austin, where she has been a member of the faculty for more than 20 years.
Wood’s research interests focus on the design and behavior of concrete structures. Early in her career, she studied the earthquake response of buildings, while more recent work is related to evaluation of reinforced and prestressed concrete bridges and development of passive sensors to detect the onset of corrosion in concrete structures. She is a member of the National Academy of Engineering. She is the immediate past president of the American Concrete Institute and is a member of its Structural Concrete Building Code Committee.
Wood received her BS in civil engineering from the University of Virginia, and her MS and PhD from the University of Illinois.
About Elizabeth D. Rockwell
A fourth generation Houstonian, Mrs. Rockwell was an Executive Director, Private Client Division of CIBC Oppenheimer Corp. She was widely recognized as an expert in retirement, estate, investment, and tax planning. She was an early proponent of the Keogh and IRA plans, for which she has been nationally recognized.
In 1991, she qualified to be a member of the Million Dollar Round Table as well as the Texas Leaders Round Table. Since 1990 she had authored a monthly column for the Houston Chronicle.
Mrs. Rockwell served as President of the UH College of Business Administration Foundation Board, as a member of the Dean’s Advisory Board, and was an Executive Professor for the college. She also served as a member of the advisory board of the Health Law and Policy Institute and as a Trustee of the University of Houston System’s Foundation, as well as a member of the UH System’s Planned Giving Council.
Mrs. Rockwell served on the Board of Governors for the Houston Forum, and as a Board member of the American Red Cross, the Greater Houston Women’s Foundation, the University of Houston Alumni Organization, and the Greater Houston Preservation Alliance. She was a member of the River Oaks Business Women’s Exchange Club, the National Tax Sheltered Annuity Association, the Texas Association of College Teachers, and the Houston Association of Life Underwriters.
Among her numerous honors, she has received an Honorary Doctorate of Humane Letters from the University of Houston, the Distinguished Alumna Award from the Houston Alumni Organization and from the UH College of Business Administration. Throughout the years she has been recognized for her many achievements by the Education Foundation of Harris County, the Houston Community College System’s Television Station Advisory Council, and the Houston Mayor’s READ Commission.
The Houston Alumni Center is home to the Elizabeth D. Rockwell President’s Suite. In September 1997, the Elizabeth D. Rockwell Career Services Center was opened in the UH College of Business Administration. She endowed the Chair for the Dean of the M.D. Anderson Library.
Mrs. Rockwell was listed in the Who’s Who in the South and Southwest; Who’s Who in finance and Industry; Who’s Who of American Women; and Who’s Who in the World.