Exposure to harsh winter conditions can cause cracking in concrete bridges, leaving interior structural supports vulnerable to outside elements. De-icing salt, applied to wintry roads, often penetrates the cracks, causing these structural supports to corrode. Salt water has the same effect on coastal infrastructure. Over time, this corrosion destabilizes the concrete, resulting in costly repairs and unsafe conditions.
Researchers at Marshall University (MU) and the University of Virginia (UVA) are exploring how fiber-reinforced plastic (FRP) wraps, a technology that has been around for over 20 years, might offer a fresh approach to repairing and fortifying damaged bridges. Currently used primarily for specialized applications, such as earthquake resistance, FRP wraps hold the promise of extending the service life of corrosion-deteriorated concrete. In cleaning and repairing the damaged areas, then applying the optimal number of FRP sheets in the optimal number of directions, the life of the structure could be saved for many more years. However, cost/benefit analyses and assessment criteria are needed before State DOTs widely adopt the approach.
Working closely with WVDOH and VDOT, the research team is developing a practical guidebook for selecting suitable bridges and outlining evaluation, design, construction and training guidelines. Wael Zatar, PhD, Dean of the College of Information Technology and Engineering at MU, Hai Nguyen, PhD, Research Scientist in Civil Engineering at MU, and Osman Ozbulut, PhD, Assistant Professor in Civil Engineering at UVA, are undertaking a non-destructive evaluation approach for projects in West Virginia, a state already using FRP for infrastructure repair. Initially, they will use a variety of damage and inventory parameters to develop a prioritized classification process to help practitioners identify possible candidate structures.
Zatar serves as chair of the National Committee on Structural Fiber Reinforced Polymers for the Transportation Research Board, a group of national and international experts committed to expanding the current state of knowledge and practice related to repair technologies. He suggested that this MATS UTC-funded project is an important component in understanding the optimum use of FRP wraps.
“Although FRP is a costly material, it offers clear benefits in terms of remedial repairs,” he explained. “Maintenance on these deficient structures is imperative and, if not done correctly or in a timely manner, may result in the need for complete bridge replacement. If we can develop an assessment tool that weighs the long-term repair and replacement benefits of FRP wraps against the cost, then we can make significant advances in efficient and sustainable structural safety improvements.”
Ultimately, the team plans to deliver an FRP reference report for bridge inspections and maintenance programs as well as recommendations for field implementations and classroom education initiatives.
For more information about this project, contact Dr. Zatar at email@example.com.