Performance‐based earthquake engineering assessment of a self‐centering, post‐tensioned concrete bridge system

Abstract

Highway bridges in highly seismic regions can sustain considerable residual displacements in their columns following large earthquakes. These residual displacements are an important measure of post-earthquake functionality, and often determine whether or not a bridge remains usable following an earthquake. In this study, a self-centering system is considered that makes use of unbonded, post-tensioned steel tendons to provide a restoring force to bridge columns to mitigate the problem of residual displacements. To evaluate the proposed system, a code-conforming, case-study bridge structure is analyzed both with conventional reinforced concrete columns and with self-centering, post-tensioned columns using a formalized performance-based earthquake engineering (PBEE) framework. The PBEE analysis allows for a quantitative comparison of the relative performance of the two systems in terms of engineering parameters such as peak drift ratio as well as more readily understood metrics such as expected repair costs and downtime. The self-centering column system is found to undergo similar peak displacements to the conventional system, but sustains lower residual displacements under large earthquakes, resulting in similar expected repair costs but significantly lower expected downtimes.

Probabilistic collapse resistance and residual drift assessment of buildings with fluidic self‐centering systems

“…However, increases in preload and damping have important effects in reducing the residual drift and the peak story drift, respectively [23]. The former is of particular interest today and is considered an important performance index [41][42][43]. This section concentrates on an evaluation of the performance of structures with and without fluidic self-centering systems based on the residual drift.…”

Sensitivity Analysis of Pile Supported Wharves against Directional Uncertainty of Earthquakes Using Fragility Curves

“…This analysis mainly discusses the meaningful value for an owner or decision maker of the structure. This value includes direct pecuniary losses, casualties, and downtime [5]. In the following, a case study is considered to develop fragility curves through the procedure of PEER methodology.…”

“…After the pushover analyses, the structural analysis is continued by performing one dynamic analysis. According to previous studies, one of the common dynamic analysis which is well integrated to this frame work, especially when seismic uncertainty is under question, is IDA method [5]. There are two important steps in basis of IDA method.…”

“…Therefore, Pacific Earthquake Engineering Research Center (PEER) proposed a systematic methodology which seeks to thoroughly assess individual components related to earthquake engineering and to provide the probabilistic framework which combines these components for the seismic design and assessment of structures in conjunction with the most recent development in engineering science. Since the procedure of this framework is carried out based on a probabilistic manner, it can take uncertainties into account [5][6]. Along with the recent developments in design philosophy, one of the developments in earthquake engineering in analytical approaches has been Incremental Dynamic Analysis (IDA) method proposed by Cornell et al in 2002, which is well integrated into this probabilistic framework.…”

Seismic Behavior of Posttensioned Concrete Bridge Piers with External Viscoelastic Dampers

“…The experimental results by Cheng [9] demonstrated that the bridge model could rock up to 5% of the column rotation without damage or residual displacement. In addition, given the increasing interest in self-centering bridge piers, Wacker et al [11] and Lee and Billington [12] also developed design procedures and a seismic assessment method based on the performancebased earthquake engineering framework. Whereas self-centering structures with posttensioned tendons exhibit high performance for eliminating residual displacement, it is also found that this type of structure contains inherent defects of low energy dissipation, which increases the seismic responses of the structures.…”