ABSTRACT
Post Tensioned Hanger Rods are used in Cable Stayed and Tied Arch Bridges. As these bridges become old, it is important to have an idea of the service life of these Hanger Rods. This will enable a proper maintenance plan to be implemented in a timely manner. For new designs, provisions can be incorporated to enhance the service life of the Hanger Rods. The biggest challenge for the hanger rods is corrosion. The corrosion rate of metals will depend on the atmosphere of the rod and how well it is protected from moisture and other chemicals. Hot dip galvanizing of the rods is common. Such organizations like the American Galvanizers Association have published corrosion rates of Zinc and other metals. Their Zinc Coating Life Predictor can be used to predict the service life of the rods. Encasing the rods in steel pipes can increase the service life. Sealing the pipes or filling them with grout can further enhance it. This paper describes how the service life of hanger rods were calculate for a bridge in the California High Speed Rail Project.
