Seismic performance of reinforced concrete bridge columns constructed with grade 80 reinforcement

Graduation date: 2014The research presented in this thesis assessed the use of high strength steel (HSS) reinforcement for use in reinforced concrete (RC) bridge columns. HSS is not currently allowed in reinforced concrete bridge columns due to a lack of information on the material characteristics and performance information when used in RC bridge columns. Potential benefits in construction, performance, and economics justify the need for research. This research investigated the performance of HSS (ASTM A706 Grade 80 reinforcement) embedded in half-scale RC bridge columns. Column design followed standard design methodologies used by federal and state highway agencies. Six columns were subjected to lateral cyclic loadings, three columns were constructed with Grade 60 reinforcement and three columns were constructed with Grade 80 reinforcement. Results indicate that the columns constructed with Grade 80 reinforcement achieved similar resistances and displacement 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 and typically exhbitied larger curvature ductility values than the columns constructed with Grade 80 reinforcement. The effects of the longitudinal reinforcement ratio and moment-shear span ratio on column performance were similar between columns constructed with Grade 60 reinforcement and columns constructed with Grade 80 reinforcement. The results from this research present a promising step towards the implementation of Grade 80 reinforcement in the design and construction of RC bridge columns, within the bounds of the variables used in the testing program