Refugio County, Texas has a humid, subtropical climate. Given the humidity and proximity to the coast, brackish water in streams and drainage ditches corrodes the county's highway bridges and increases maintenance costs. This article describes a study to address this corrosion issue by using customized, fiber-reinforced polymer (FRP) composite beams in bridge construction. These FRP beams were used in the replacement of a drainage ditchbridge in Refugio County in 2007. The new bridge has eight customized FRPflanged U-shaped beams and a concrete deck. The beams are 15 m long by 76cm high, with a composite structure that provides optimal deflection under load. The new beams weigh approximately 2,270 kg each and sit on abutments. The beams were fabricated using a vacuum infusion process. Before installation of the beams, an acoustic emission evaluation test was conducted on two of the beams. The test verified the performance of the beams under the load criteria set forth by the project specifications. In the implementation project, researchers found that the structure had more stiffness under loading than was calculated in the design phase. The Texas Department of Transportation's future use of this product will be based largely oncost and flexibility of use.
Abstract