Optimal design of supplemental viscous dampers for irregular shear-frames in the presence of yielding

Abstract

SUMMARYA methodology for the optimal design of supplemental viscous dampers for regular as well as irregular yielding shear-frames is presented. It addresses the problem of minimizing the added damping subject to a constraint on an energy-based global damage index (GDI) for an ensemble of realistic ground motion records. The applicability of the methodology for irregular structures is achieved by choosing an appropriate GDI. For a particular choice of the parameters comprising the GDI, a design for the elastic behavior of the frame or equal damage for all stories is achieved. The use of a gradient-based optimization algorithm for the solution of the optimization problem is enabled by ÿrst deriving an expression for the gradient of the constraint. The optimization process is started for one 'active' ground motion record which is e ciently selected from the given ensemble. If the resulting optimal design fails to satisfy the constraints for other records from the original ensemble, additional ground motions (loading conditions) are added one by one to the 'active' set until the optimum is reached. Two examples for the optimal designs of supplemental dampers are given: a 2-story shear frame with varying strength distribution and a 10-story shear frame. The 2-story shear frame is designed for one given ground motion whereas the 10-story frame is designed for an ensemble of twenty ground motions.

Optimal locations for MR dampers in civil structures using improved Ant Colony algorithm

“…Garcia and Soong [5] presented a sequential search algorithm for the optimal design of damper formation. Lavan and Levy [6] proposed a method for the optimal design of viscous dampers based on a global damage index. Interesting studies concerning the allocation and sizing of viscous dampers are presented by Main and Krenk [7] and by Engelen et al [8].…”

Performance-Based Placement of Manufactured Viscoelastic Dampers for Design Response Spectrum

“…Lavan and Levy (2005) chose energy-based damage indices based on the hysteretic energy dissipated by the restoring force divided by its hysteretic energy at failure. Tan et al (2005) and Liu et al (2005) considered an acceleration-based criterion in addition to the interstory drift criteria.…”

Seismic Behavior and Design of Wall–EDD–Frame Systems

“…Hence, the use of FVDs seems natural for seismic retrofitting where both displacements and forces due to earthquakes are to be decreased. Indeed, optimal design of such dampers for the purpose of seismic retrofitting of frame structures received much attention (Zhang and Soong, 1992;Gluck et al, 1996;Takewaki, 1997;Singh and Moreschi, 2001;Lopez-Garcia and Soong, 2002;Dargush and Sant, 2005;Lavan and Levy, 2005, 2009Aydin et al, 2007;Lavan et al, 2008;Lavan and Dargush, 2009;Adachi et al, 2013;Aguirre et al, 2013;Kanno, 2013;Martínez et al, 2013;Sonmez et al, 2013;Gidaris and Taflanidis, 2014;Hatzigeorgiou and Pnevmatikos, 2014;Lavan and Amir, 2014;Lin et al, 2014;Lavan, 2015). To allow a quick examination of whether such devices are a good alternative, simple methodologies for initial design were proposed as well (FEMA 356, 2000;Palermo et al, 2013;Landi et al, 2014;Rama Raju et al, 2014).…”