Project Title

Deployment of Ground Penetrating Radar and Ultrasonic Tomographer Non-Destructive Techniques for Assessment of Corrosion-Deteriorated Adjacent Prestressed Concrete Box Beams

Collaborating Universities

Marshall University
One John Marshall Drive
Huntington, WV 25755
1-800-642-3463
www.marshall.edu

University of Virginia
351 McCormick Dr.
P.O. Box 400742
Charlottesville, VA 22904-4742
www.virginia.edu

Principal Investigator(s)

Zatar, Wael (Marshall)
Email: zatar@marshall.edu

Nguyen, Hai (Marshall)
Email: nguyenhai@marshall.edu

Ozbulut, Osman (UVA)
Email: ozbulut@virginia.edu

Total Project Costs

$149,999

Start Date

05/01/17

Completion Date

05/31/18

Description

Civil infrastructure systems play an important role in every aspect of the United States. The average age of the nation’s 607,380 bridges is approximately 42 years old and one in nine of the nation’s bridges is rated as structurally deficient. The United States is facing a major challenge to build safe and sound bridge systems with long-term durability, low maintenance costs and short construction periods. About 26 percent of the highway bridges in the United States are in need of repair or replacement, and a large number of these deficient bridges are reinforced or pre-stressed concrete structures. The cost of the United States infrastructure rehabilitation is estimated at over 1.5 trillion dollars over the next five years, with corrosion deterioration costs due to deicing salt and sea salt estimated at $150 billion. The United States Congress has recently approved a multi-year, $305 billion highway, transit and railway authorization bill to provide much-needed funds for state DOTs to fix deteriorated and deficient transportation infrastructure. The corrosion of reinforcing steel and prestressing strands is one of the major causes of deterioration, reduced durability or even failure of reinforced and prestressed concrete bridge structures. Corrosion does not only destroy the smooth riding quality of the bridge deck, but it could eventually compromise the structural integrity and safety of the bridge. Over the past few years, West Virginia Department of Transportation (WVDOT) has provided sizable funds to support the Lead Investigator’s work to assess the service life of corrosion-deteriorated reinforced concrete (RC) members in highway bridges (Zatar 2014). Bridges built with adjacent precast, pre-stressed concrete box beams are very popular and economical in all MATS States and nationwide. They have been used in the past two decades to foster the Accelerated Bridge Construction (ABC) concept. According to a recent National Bridge Inventory data, adjacent concrete box beams constitute 17 percent of bridges built annually on public roads (Naito and Warncke 2008 and Russell 2009). Without proper guidance, corrosion problems may be exacerbated for adjacent prestressed concrete (PC) box beams. Any rational decision regarding maintenance, repair, or replacement of the deteriorated members should take into account the member’s condition, the extent of deterioration, the expected remaining service life and the impact of alternative maintenance and repair options on the service life of the members. While visual inspection might provide a qualitative estimate of the damage, the specific location along a strand and the damage level cannot be clearly defined. There have been multiple cases where accurate condition assessments have revealed insufficient capacities and standard remediation and rehabilitation were inadequate. Evaluations of strand corrosion, broken strands and duct voids of adjacent PC box beams are essential in developing accurate and reasonable repair and maintenance strategies. This project aims at identifying the feasibility of using Ground Penetrating Rader (GPR) and Ultrasonic Tomographer to assess prestressed tendons’ condition, to provide detailed information about concrete deterioration and to assist with assessment and management of corrosion-deteriorated adjacent box beams in the Mid-Atlantic States.

Research Goals and Objectives: The geographical location of MATS States, with associated environmental and coastal-induced practices and the need for salt spraying during the winter produce the greatest challenges for bridge infrastructure maintenance, sustainability and management efforts. The primary goal of this project is to develop, maintain and implement accurate and manageable processes to evaluate, maintain and repair corrosion-deteriorated adjacent precast box beams in PC bridge infrastructure in the MATS States. Non-destructive techniques and equipment will be used to evaluate existing bridge structures. The project’s primary objectives are:

  • Conduct laboratory testing to examine the applicability and accuracy of using GPR and Ultrasonic Tomographer to evaluate the corrosion damage of tensioning strands and strand-to-concrete bond. Limitations and precautions identified from the lab studies will be considered in the field studies.
  • Conduct field testing and evaluation of three corrosion-deteriorated adjacent precast box beams in PC bridge infrastructure. Two-dimensional visualization mapping of the reinforcement and prestressing tendons corrosion and chloride contamination will be the primary focus.
  • Suggest evaluation techniques to assist State DOT engineers, inspectors and maintenance personnel to determine remaining service life and appropriate cost-effective action plans.
  • Suggest customized service life extension methods based on the field testing results.