In its efforts to find more durable, affordable construction methods, TxDOT has constructed a drainage-ditch bridge out of fiber-reinforced polymer (FRP) composite beams.

The structure, which replaces a single-span girder bridge, is 50 feet long and 32 feet wide and sits 35 miles from Corpus Christi. The second FRP bridge in the state, it consists of a concrete deck and customized FRP flanged U-shaped beams. The composition of the beams makes them durable and corrosion-resistant.

After the beams were fabricated by Independence, Mo.-based MFG Construction Products Co., they were placed on-site, and the deck was placed on top, tied to the beams with horizontal pipe. Since the bridge was completed in April 2007, TxDOT's load-testing research has found the beams to be stronger than anticipated. The structure's long-term performance will be observed in coming months.