Seismic Performance Of Circular Reinforced Concrete Bridge Columns Constructed With Grade 80 Reinforcement

This project assessed the use of ASTM A706 Grade 80 reinforcing bars in reinforced concrete columns. Grade 80 is not currently allowed in reinforced concrete columns due to lack of information on the material characteristics and column performance. Six half-scale, circular columns were tested: three constructed with Grade 60 reinforcement and three constructed with Grade 80 reinforcement. Designs followed standard design methodologies used by State Highway Agencies (including AASHTO). Results indicate that columns constructed with Grade 80 reinforcement performed similar to columns constructed with conventional ASTM A706 Grade 60 reinforcement. Computational modeling was performed using OpenSees for all six columns. Results indicate that the columns constructed with Grade 80 reinforcement achieved similar resistance and displacement and curvature ductility values when compared with the reference columns constructed with Grade 60 reinforcement. The columns constructed with Grade 60 reinforcement showed larger hysteretic energy dissipation than the columns constructed with Grade 80 reinforcement.