A comparative study on the effectiveness, robustness and mistuning sensitivity of upgraded tuned mass dampers in mitigating the dynamic response of civil structures

Abstract

Upgraded tuned liquid column damper (UTLCD), tuned two-mass damper (TTMD) and double-tuned mass damper (DTMD) have been recently introduced by Cao and his research group. However, mistuning sensitivity related to the frequency and damping ratios of these absorbers, along with a comparative study of the devices, has not been investigated. To address the gaps in the previous studies, a comprehensive comparative study on the performance, robustness and mistuning sensitivity of UTLCD, TTMD and DTMD is conducted in this paper. To do this, analytical models of a single-degree-of-freedom (SDOF) structure equipped with a UTLCD, TTMD and DTMD are established. Using a novel optimization technique named balancing composite motion optimization (BCMO), the optimal parameters of these passive dampers are found. After that, the control effectiveness, the robustness against the changes in the structural properties, and the mistuning sensitivity of each vibration absorber are determined. For the optimal configurations of UTLCD, TTMD and DTMD having the same weight, this study indicates that although the UTLCD is the most effective compared with the TTMD and DTMD, it is not as robust as the TTMD or DTMD against the variation of the mass, stiffness and damping coefficient of the primary structure. The DTMD is as effective and robust as the TTMD. Furthermore, the mistuning sensitivity of the UTLCD is similar to that of the DTMD. While the sensitivity regarding the damping ratio of the UTLCD is the lowest, the damping ratio sensitivity of the TTMD is the highest.