Optimal design of supplemental viscous dampers for linear framed structures

Abstract

SUMMARYA methodology for the optimal design of supplemental viscous dampers for framed structures is presented. It addresses the problem of minimizing the added damping subject to a constraint on the maximal interstorey angular drift for an ensemble of realistic ground motion records while assuming linear behaviour of the damped structure. The solution is achieved by actually solving an equivalent optimization problem of minimizing the added damping subject to a constraint on a maximal weighted integral on the squared angular drift. The computational e ort is appreciably reduced by ÿrst using one 'active' ground motion record. If the resulting optimal design fails to satisfy the constraints for other ground motions from the original ensemble, additional ground motions (loading conditions) are added one by one to the 'active' set until the optimum is reached. An e cient selecting process which is presented herein will usually require one or two records to attain an optimum design.Examples of optimal designs of supplemental dampers are presented for a 2-storey shear frame and a 10-storey industrial frame. The 2-storey shear frame is required to withstand one given ground motion whereas the 10-storey frame is required to withstand an ensemble of twenty ground motions. The resulting viscously damped structures have envelope values of interstorey drifts equal or less than the target drifts.

A noniterative design procedure for supplemental brace–damper systems in single‐degree‐of‐freedom systems

“…Most of the solutions proposed for sizing dampers have been based on iterative approaches [3][4][5][6]. In a practical context however, procedures offering a direct solution have the advantage of being quick and easy to apply and in some situations could be more convenient to use than those based on numerical optimisation.…”

An optimal design procedure for a simple frame equipped with elastic-deformable dissipative braces

“…Lavan and Levy [15,16] proposed a methodology for the optimal design of supplemental viscous dampers for framed structures. It is based on the minimization of the added damping of prelocated dampers subject to a constraint on the maximal inter-story drift, for a frame excited by an ensemble of realistic ground motion records while assuming linear behavior of the damped structure.…”

Supporting brace sizing in structures with added linear viscous fluid dampers: A filter design solution

“…The structure has been extensively studied before in [13] and [25]. The condensed stiffness matrix matrices that neglects axial deformations is taken from the references as …”

“…Over many years, research efforts have been aimed at reliable and cost-effective design practices. Optimal design methodologies for passive dampers based on a number of theories have been proposed for determining both damper sizes as in [7][8][9][10][11] and damper locations as in [12][13][14][15] among others. They commonly differ on how the optimisation problem is addressed and in which cost function and constraints the optimisation problem are subjected to.…”