Keywords: Reinforced concrete bridge columns. Longitudinal reinforcement. Low cycle fatigue behavior. Plastic hinges. Fatigue life relationships. Cumulative damage. Failure modes. Reinforcing bars. Strain amplitude. Plastic strain. Stress strain behavior. Damage indices.
Abstract: In an effort to investigate the cumulative seismic damage in reinforced concrete bridge piers, the authors first examined the response of model bridge columns to constant amplitude and random cyclic displacement amplitudes. They describe preliminary work that was done to analyze experimental data generated from previous testing. They also evaluate selected damage models in terms of their ability to track progressive damage. The report also provides details of the experimental setup and general issues regarding inelastic testing procedures of reinforcing bars. Experimental results from constant amplitude tests and variable amplitude (simulated seismic loadings) tests are also given. Finally, a systematic evaluation of the obseved results and the application of fatigue-life models to the recorded data are presented. The report concludes with a discussion of significant findings and recommendations for future work. (Abstract adapted from text).