An innovative tuned liquid damper for vibration mitigation of structures

Abstract

Tuned liquid dampers (TLDs) have been widely used for the vibration mitigation of structures. Conventional TLDs (CTLD) can only be tuned to one sloshing frequency. TLDs’ sloshing frequency is tuned to the fundamental period of structures because the dynamic response of the first mode shape is often dominant. In tall buildings and irregular structures, higher mode shapes’ response should also be controlled. Multiple tuned TLDs have been employed to control the dynamic response of higher mode shapes. However, in addition to a higher maintenance cost, multiple TLDs require a larger installation space. In this study, a modified TLD (MTLD) is introduced to mitigate multiple-mode shapes’ vibration simultaneously. The efficiency of the MTLD is demonstrated through several shake table tests conducted on a scaled 3-story structure. Free vibration tests show that the MTLD reduces the root mean square (RMS) of third floor’s displacement responses 1.9 times more than the CTLD. Besides, at the first resonance frequency (RF), the MTLD decreases the peak displacement response (PDR) and the peak acceleration response (PAR) of the third floor, respectively, 44% and 42% more than the CTLD. Results also indicate that while the CTLD cannot decrease the PAR of the third floor at the second RF, the MTLD decreases it by 44%. Moreover, at the second RF, MTLD reduces the PDR of the second floor 42% more than the CTLD