Ductility evaluation for typical existing R /C bridge columns in the eastern USA

Results of nonlinear static pushover analyses of five bridges located in Pennsylvania are presented. The bridges, which vary from single column bents to multiple column bents, have reinforced concrete columns with ties at 12 in. spacing. The objective of the part of the study that is presented in the paper is to estimate displacement ductility and force reduction factors for the selected bridges. The procedures used to obtain moment-curvature relations and to perform nonlinear static pushover analysis using linear elastic analysis software are described. Calculated values for displacement ductility factors and response modification factors (R-values) are presented. Observations made from the results of a literature review on experimental evidence for ductility of deficient columns are also discussed.