Experimental Cyclic Behavior of Hollow-Section Bridge Piers with Different Transverse Reinforcement Details

Abstract

The main purpose of this paper is to present an experimental and numerical study concerning the influence of the transverse reinforcement details on the cyclic behavior of RC hollow bridge piers. Another strong motivation for this work relies on the fact that rectangular RC hollow piers exhibit a peculiar structural behavior, close to structural wall, and therefore it is more difficult to assess their cyclic response with simplenumerical tools. Being representative of typical bridge construction, several RC piers were tested at LESE - FEUP (Laboratory for Earthquake and Structural Engineering of the Faculty of Engineering of University of Porto). Cyclic loading experimental tests were carried out on rectangular hollow-section piers in order to study two main aspects: i) the influence of shear effects on the seismic response and, ii) the influence of transverse reinforcement details, in terms of cross section area with the correspondent effects on the shear capacity and concrete confinement. In addition, numerical simulations of the experimental tests were systematically carried out allowing complete and consistent interpretations of experimental results, for which the most important aspect was found associated with the shear influence on pier response. The adopted numerical methodology (Damage Model) allows realistic simulations of the non linear behavior, particularly when significant shear component is involved. In fact, shear deformation and also the shear mode failures were quite well simulated by this numerical strategy that also allowed identifying some relevant modeling issues that are likely to affect the quality of simulations.