Self‐centering structural systems with combination of hysteretic and viscous energy dissipations

TLDR

AFS systems combine velocity‑dependent and displacement‑dependent energy dissipation to enable self‑centering and counteract near‑fault earthquakes. The study introduces Advanced Flag‑Shaped (AFS) systems that integrate self‑centering elements with combinations of hysteretic, viscous, or visco‑elasto‑plastic energy dissipators in series or parallel. The authors performed nonlinear time‑history analyses of four SDOF models under 40 ground motions and a parametric study varying λ1 and λ2 to assess AFS system performance across periods and strength levels. AFS systems with parallel hysteretic‑viscous dissipators outperform conventional systems on three performance indices, friction‑slip series viscous elements reduce peak acceleration and base shear, and optimal λ1 (0.8–1.6) and λ2 (0.25–0.75) ranges are recommended for adequate self‑centering and dissipation. © 2010 John Wiley & Sons, Ltd.

Abstract

Abstract This paper presents an innovative set of high‐seismic‐resistant structural systems termed Advanced Flag‐Shaped (AFS) systems, where self‐centering elements are used with combinations of various alternative energy dissipation elements (hysteretic, viscous or visco‐elasto‐plastic) in series and/or in parallel. AFS systems is developed using the rationale of combining velocity‐dependent with displacement‐dependent energy dissipation for self‐centering systems, particularly to counteract near‐fault earthquakes. Non‐linear time‐history analyses (NLTHA) on a set of four single‐degree‐of‐freedom (SDOF) systems under a suite of 20 far‐field and 20 near‐fault ground motions are used to compare the seismic performance of AFS systems with the conventional systems. It is shown that AFS systems with a combination in parallel of hysteretic and viscous energy dissipations achieved greater performance in terms of the three performance indices. Furthermore, the use of friction slip in series of viscous energy dissipation is shown to limit the peak response acceleration and induced base‐shear. An extensive parametric analysis is carried out to investigate the influence of two design parameters, λ 1 and λ 2 on the response of SDOF AFS systems with initial periods ranging from 0.2 to 3.0 s and with various strength levels when subjected to far‐field and near‐fault earthquakes. For the design of self‐centering systems with combined hysteretic and viscous energy dissipation (AFS) systems, λ 1 is recommended to be in the range of 0.8–1.6 while λ 2 to be between 0.25 and 0.75 to ensure sufficient self‐centering and energy dissipation capacities, respectively. Copyright © 2010 John Wiley & Sons, Ltd.