Estimation of the modal mass of a structure with a tuned-mass damper using H-infinity optimal model reduction

Abstract

Accurate estimation of the modal mass of a structure is essential for analyzing the structural response under disturbance and for designing mass-type control devices used to enhance the serviceability of the structure. The modal mass of a real structure differs from that of the mathematical model due to the error introduced by the assumptions made for analysis and by the change in dynamic characteristics occurring during the construction process. In this study, a procedure is proposed for estimating the modal mass of a real structure with a tuned-mass damper based on the H-infinity optimal model reduction technique. The modal mass is obtained from the relationship between the observability–controllability matrices realized from the system identification and the typical two-degree-of-freedom state space model. The proposed method is verified through the analysis of three model structures.