Optimization of seismic isolation systems via harmony search

Abstract

In this article, the optimization of isolation system parameters via the harmony search (HS) optimization method is proposed for seismically isolated buildings subjected to both near-fault and far-fault earthquakes. To obtain optimum values of isolation system parameters, an optimization program was developed in Matlab/Simulink employing the HS algorithm. The objective was to obtain a set of isolation system parameters within a defined range that minimizes the acceleration response of a seismically isolated structure subjected to various earthquakes without exceeding a peak isolation system displacement limit. Several cases were investigated for different isolation system damping ratios and peak displacement limitations of seismic isolation devices. Time history analyses were repeated for the neighbouring parameters of optimum values and the results proved that the parameters determined via HS were true optima. The performance of the optimum isolation system was tested under a second set of earthquakes that was different from the first set used in the optimization process. The proposed optimization approach is applicable to linear isolation systems. Isolation systems composed of isolation elements that are inherently nonlinear are the subject of a future study. Investigation of the optimum isolation system parameters has been considered in parametric studies. However, obtaining the best performance of a seismic isolation system requires a true optimization by taking the possibility of both near-fault and far-fault earthquakes into account. HS optimization is proposed here as a viable solution to this problem.

A Novel Hybrid Harmony Search Approach for the Analysis of Plane Stress Systems via Total Potential Optimization

“…The sequential HS algorithm was proposed to find the shape optimization of structural systems, including frequency constraints [20]. For the control of the structures, HS-based methodologies are also perfectly applied for the placement of dampers [21], tuned mass dampers [22,23], and base isolators [24]. In structural health monitoring, Jin et al proposed and improved HS for optimal sensor placement to crane structures [25].…”

Curved surface sliders with friction damping, linear viscous damping, bow tie friction damping, and semiactively controlled properties

“…Kovaleva et al stated that the CSS damping must be sufficiently high to suppress resonance effects and derived optimal CSS parameters for various optimization functions. Nigdeli et al used a linearized model of the structure with CSS to derive the optimum CSS parameters that minimize structural acceleration with the constraint of a maximum CSS displacement. Also, a linearized model of the structure with CSS was adopted by Kamalzare et al to keep the computational effort within reasonable limits in the search for optimum damping.…”

Parameter Optimization of the Kdamper Concept in Seismic Isolation of Bridges Using Harmony Search Algorithm

“…Although, a detailed description of the HS algorithm can be found in [30] and [35][36][37], the four basic steps of the algorithm are the following:…”

“…As far as structural problems are concerned, HS has been successfully applied to the optimum design of truss structures [32], steel sway frames [33] and grillage systems [34]. Recently, HS has been employed for the optimum design of the implementation of TMDs to multistory buildings [35,36].…”