Seismic response control of base-isolated buildings using multiple tuned mass dampers

Seismic response of a base-isolated building equipped with single tuned mass damper (STMD), multiple tuned mass dampers (MTMDs), and distributed multiple tuned mass dampers (d-MTMDs) under real earthquake ground motions is investigated. Numerical study is carried out using analytical models of five-, 10-, and 15-storey base-isolated buildings equipped with the STMD, MTMDs, and d-MTMDs. The buildings are modeled as shear-type structure with a lateral degree of freedom at each floor level, and the buildings are isolated using the laminated rubber bearing, lead-core rubber bearing, friction pendulum system, and resilient-friction base isolator. The coupled differential equation of motion for the buildings are derived and solved in the incremental form using Newmark's step-by-step method of integration. From the numerical study conducted, it is concluded that installing a tuned mass damper at each floor level of a base-isolated building reduces the structural response in terms of top floor acceleration and bearing displacement. It is found that installing the MTMDs and d-MTMDs are significantly beneficial in reducing top floor acceleration as compared with the STMD. Further, almost comparable reduction in the bearing displacement could be obtained by installing the STMD, MTMDs at top, and d-MTMDs in the base-isolated buildings. The d-MTMDs are more beneficial as compared with the STMD and MTMDs as otherwise huge controller mass can now be divided and distributed on different floor levels.