SEISMIC PERFORMANCE OF REINFORCED CONCRETE RECTANGULAR HOLLOW BRIDGE COLUMNS

To investigate the seismic performance of hollow reinforced concrete (RC) bridge columns and obtain quantitative parameters for the requirements of performance-based seismic design, twelve specimens with rectangular cross section were tested under constant axial load and cyclic bending. Parametric studies were carried out on the aspect ratio, axial load ratio, longitudinal reinforcement ratio, and transverse reinforcement ratio. The key damage states from experimental observations can be related to engineering parameters, which can satisfy quantitative criteria of performance-based seismic design for bridges. The hysteretic behavior of specimens is simulated with a fiber model using OpenSees FE platform. The force-displacement relationship hysteretic curves of bridge column specimens derived from the fiber element model agree well with experimental results. Analysis of the experimental results suggested that key damage states of residual cracking, cover spalling, and core crushing can also be related to engineering parameters, such as longitudinal reinforcement tensile strain and concrete compressive strains, using cumulative probability curves. The experimental results showed that the ductility coefficient varies from 3.71 to 8.29 and the equivalent viscous damping ratio varies from 0.19 to 0.31, meeting the requirements of seismic design. The hollow RC rectangular bridge columns with configurations of transverse reinforcement in this paper have excellent performance, and may be considered as a substitute for current hollow RC rectangular section configurations described in Guideline for Seismic Design of Highway Bridges (JTG/T B02-01-2008).