Abstract:
Tall buildings are necessary need of modern world due to shortage of land in commercial areas. Earthquake and wind loads produce undesirable vibrations in these buildings. There are several vibration control techniques available for mitigation of undesirable vibrations. Provision of an additional tuned mass damper at top of the structure is one of the classic techniques being used in several high-rise buildings. Tuned mass damper is a passive control technique used for vibration mitigation of high-rise structures subjected to wind and seismic loadings. Basic principle of tuned mass damper is to dissipate the energy produced from vibration of structures with help of out of phase vibrations of tuned mass damper with the structure. Irregularity in structure increases the vibrations produced from these loadings. In this study, a detailed experimental work is carried out for vibration mitigation of a 4-storey structure having mass irregularity at its 4th floor using single tuned mass damper (STMD) and multiple tuned mass dampers (MTMDs) against different harmonic and seismic loadings. Positions of STMD and MTMDs were varied along each floor and all possible configurations of STMD and MTMDs were tested against these loadings. For comparison acceleration response of each storey measured with help of portable accelerometer for all configurations of STMD and MTMDs were compared with that of the uncontrolled structure. It is found that under all types of loadings STMD reduces acceleration response of all floors of uncontrolled structure similarly all configuration of MTMDs shows further reduction in acceleration response showing the efficiency of MTMDs over STMD in irregular structures. Key words: STMD, MTMDs, vibration control, irregular structure.
