Efficiency of tuned liquid dampers in mitigating vibrations of structures with mass eccentricity

Abstract

Background: Tuned liquid dampers (TLDs) have been successfully installed on different types of structures for vibration mitigation against wind or earthquake forces. However, the effectiveness of TLDs in mitigating the dynamic responses of buildings with large mass eccentricity has not been well investigated. Method: In this study, a scaled-down one-bay 3-story structure with a 1 m span length and a total height of 2.65 m was constructed and subjected to free vibration and harmonic excitations. TLDs with mass ratios ranging from 1 to 5% were installed on the roof of the building. Moreover, to impose in-plane torsional moments to the reference structure, the location of floors’ mass was shifted 0.15 m and 0.3 m away from the geometric centroid. The peak displacement and acceleration responses (PDR and PAR) were measured at the roof level of the reference structure with and without the effect of the torsional moment. Results: The obtained results indicated that, at the resonance frequency (RF), TLDs could successfully mitigate the PDRs and PARs even at the presence of torsional moments. Moreover, TLDs reduced the PDRs more than the PARs. Besides, an increase in the mass ratio up to 5% enhanced the effectiveness of TLDs in reducing the peak responses.