Title: Residual Seismic Performance of Reinforced Concrete Bridge Piers After Moderate Earthquakes

Author(s): Young-Soo Chung, Chang Kyu Park, and Christian Meyer

Publication: Structural Journal

Volume: 105

Issue: 1

Appears on pages(s): 87-95

Keywords: fiber-reinforced concrete; lap splice; pier; reinforced concrete; seismic; transverse confinement.

DOI: 10.14359/19072

Date: 1/1/2008

Abstract:
An experimental investigation was conducted to evaluate the seismic ductility of previously damaged concrete columns. Eight circular concrete columns 600 mm (23.6 in.) in diameter and 1500 mm (59.0 in.) in height were constructed with three test parameters: confinement ratio, lap-splice of longitudinal steel, and retrofitting fiber-reinforced polymer (FRP) materials. The objective of this research was to subject reinforced concrete (RC) bridge piers to artificial earthquake motions using a pseudo-dynamic test (PDT), and then to examine their seismic performance in a quasistatic test (QST). The seismic enhancement of FRP wraps was also investigated. Six specimens were loaded to induce damage by a series of four artificial earthquakes, which were developed by the Korea Highway Corporation (KHC), to be representative of earthquakes in the Korean peninsula. Following the PDT, the six predamaged specimens were subjected to inelastic cyclic loading while under a constant axial load of 10% of the column axial capacity. Two reference specimens without predamage were subjected to similar quasi-static loads. Test results showed that all specimens behaved almost linearly under moderate artificial earthquakes (PDT). Except for the ordinary specimens with lap-spliced longitudinal bars, most specimens predamaged during the PDT generally demonstrated good residual seismic performance. The predamage introduced during the PDT in ordinary specimens lowered their seismic performance. RC bridge specimens retrofitted with fiber composite wraps in the potential plastic hinge region exhibited enhanced flexural ductility.