Llano River Bridge - Mason County, TX - Truss Bridges on Waymarking.com

"The State Highway 9 Bridge at the Llano River consists of two riveted Warren polygonal-chord through truss spans, 12 concrete girder approach spans and two steel I-beam spans. The bridge serves southbound lanes on US 87, former State Highway (SH) 9, about 10 miles southeast of Mason, the Mason County seat. The bridge links Mason with Fredericksburg, the Gillespie County seat. Located in the Westem Cross Timbers region of North Central Texas, Ma.son County has an economy based primarily on cattle ranching and diversified agriculmre.

The Llano River bridge was reconstructed from the previous bridge, which washed out in a flood. In addition to raising the bents and exterior piers, the effort involved erecting new truss spans and constructing a new center pier. Texas Highway Department (THD) engineers custom-designed the bridge's two new truss spans. These 180-foot spans have a Warren truss configuration with a polygonal top chord. A double row of 9-inch deep channels serve as truss railing. The truss spans rest on three reinforced concrete piers consisting of battered cylindrical columns in a dumbbell configuration. New tops about 8 feet high were added to the two exterior piers. The newer center pier rests on a spreadfooling foundation with pointed ends serving as cutwaters. Reinforced concrete bents support the approach spans. These bents feature canted corners where the caps and struts frame into the columns. New bent caps supported on a series of three short columns, each about 5 1/2 feet high, were added to the bents to accommodate the raised superstructure. The approach spans feature Type D open concrete approach railing. A bronze plaque embedded in the railing end post identifies the government officials involved in the project. The plaque reads:

In 1936, Froemming Bros., Inc., constructed the Llano River bridge under contract to THD. From 1970 to 1972, THD undertook a project to turn the Llano River bridge into part of a one-way pair by constructing a companion bridge to serve northbound lanes. No other major alterations have been performed on the bridge. As such, it retains integrity of design, materials and workmanship. Because the bridge remains in place serving vehicular traffic on a state highway, it also retains integrity of location and association. Although the construction of the new bridge has somewhat compromised integrity of setting and feeling, the truss bridge retains substantial integrity overall."