ACI SP-346 Field Applications of Non-Conventional Reinforcing and Strengthening Methods for Bridges and Structures. Synopsis: This case study highlights the use of Fiber Reinforced Polymer (FRP) materials on the US 41 Highway Bridge over North Creek in Sarasota County near the Florida Gulf Coast. Design and construction involved the use of Glass-FRP (GFRP) reinforcement on the cast-in-place (CIP) concrete flat slab superstructure, Carbon-FRP (CFRP) prestressing strands on the concrete piles, and GFRP reinforced precast panels for the substructure combining a bridge bearing abutment and retaining wall system. The application of FRP prestressing and reinforcing is promoted by the Florida Department of Transportation (FDOT) under their Transportation Innovation Challenge initiative. Soldier-pile retaining walls are a commonly used system in southeastern US coastal states, but the incorporation of innovative materials such as CFRP-prestressing for piles and GFRP-reinforcing for concrete panels is not yet widespread. Comparison of lateral stability results of this wall system during construction and in the final condition is discussed. In addition, to describing the preferred FRP-PC/RC solution adopted for this project, a comparison is provided to a recently completed adjacent bridge that utilized a conventional carbon-steel PC soldier-pile and RC precast panel wall system. A further comparison is presented for the design and cost of the wall system based on the project design criteria (ACI 440.1R, ACI 440.4R, and 2009 AASHTO LRFD Bridge Design Guide Specifications for GFRP- Reinforced Concrete, 1st Edition) with the refinements and savings possible under the newer editions. Finally, the life-cycle cost, durability and environmental benefits from the use of the innovative CFRP and GFRP reinforcing systems in this type of traditional wall system, are identified for typical urban coastal areas with extremely aggressive conditions, congested access, and challenging environmental constraints. Synopsis: Many aging concrete bridges across the United States have exhibited severe deteriorations and in urgent need of rehabilitation, retrofitting or replacement. The deterioration is caused by a combination of factors including corrosion of reinforcing steel, freeze-thaw damage and chloride/water ingress. Fiber-Reinforced Polymer (FRP) composite fibers, laminates, reinforcing bars and prestressed tendons have been successfully employed in civil infrastructure applications in the past three decades. The State of West Virginia has one of the highest percentages of structurally deficient bridges in the United States and this study covers a few case studies of the use of FRP composites for rehabilitating the State’s deficient bridges. Non-destructive ultrasonic pulse-echo testing is employed to map reinforcing rebars...
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