Seismic Control of Tall Buildings Using Distributed Multiple Tuned Mass Dampers

Abstract

The vibration control of tall buildings during earthquake excitations is a challenging task because of their complex seismic behavior.Thispaperinvestigatestheoptimumplacementandpropertiesofthetunedmassdampers(TMDs)intallbuildings, whichareemployedtocontrolthevibrationsduringearthquakes.Analgorithmwasdevelopedtospendalimitedmasseither in a single TMD or in multiple TMDs and distribute it optimally over the height of the building. The nondominated sorting genetic algorithm II (NSGA-II) method was improved by adding multivariant genetic operators and utilized to simultaneously study the optimum design parameters of the TMDs and the optimum placement. The results showed that, under earthquakeexcitationswithnoticeableamplitudeinhighermodes,distributingTMDsovertheheightofthebuildingismore effectiveinmitigatingthevibrationscomparedtotheuseofasingleTMDsystem.Fromtheoptimization,itwasobservedthat thelocationsoftheTMDswererelatedtothestoriescorrespondingtothemaximummodaldisplacementsinthelowermodes and the stories corresponding to the maximum modal displacements in the modes which were highly activated by the earthquake excitations. It was also noted that the frequency content of the earthquake has significant influence on the optimum location of the TMDs.