Bridges
Corrosion is a major threat to bridges around the world and can lead to the need for increased maintenance and repairs or, in extreme cases, failures or collapse. In the United States alone, approximately 200,000 bridges are structurally deficient or functionally obsolete. There is a need for greater understanding of corrosion mechanisms and new materials in bridges to help increase the lifetime and safety of these structures.
“Corrosion of Epoxy-Coated Rebar in Marine Bridges—Part 1: A 30-Year Perspective”
The corrosion performance over a 30-year service period of epoxy-coated rebar in marine bridges is presented. A model was developed to help predict corrosion propagation and areas to monitor for possible severe corrosion damage were identified.
"Effect of Modeling Variables upon Projection of Corrosion-Induced Bridge Post-Tension Tendon Failures"
A model to project wire and strand fractures and tendon failures in post-tensioned concrete bridges that use seven wire strands is presented. The effects of different variables, such as prestress or number of tendons, on the model are discussed.
"Corrosion of Post-Tensioned Tendons with Deficient Grout, Part 1: Electrochemical Behavior of Steel in Alkaline Sulfate Solutions"
This study explores the corrosion mechanism of steel strands in deficient grout in post-tensioned bridges. The pH of the solution that the steel strands were exposed to was determined to be important, and instability of the passive film in alkaline sulfate solutions resulted in pitting corrosion of the steel.
"Evaluation of Reinforcement Corrosion in Repaired Concrete Bridge Slabs—A Case Study"
Different corrosion measurements were performed on sections from an old bridge. It was determined that corrosion could be better predicted by using multiple evaluation methods.
