Implementation of Frequency Tuning of SATMD Using New WT Method

The semi-active variable stiffness tuned mass damper (SATMD) system is robust to change in building stiffness and damping. The control effectiveness of SATMD is dependent on the precision of frequency identification for response of high-rise building under wind excitation. The wavelet method (WT) has widely been used for studying non-stationary signals. The wavelet function varies with the different scale, so the main frequency of signal in the segment can be obtained. The new idea proposed is to use WT to identify the dominant frequency of structural response a segment time, and track its variation as a function of time to retune the SATMD. The simulation results for a TV-tower with SATMD shows that SATMD is particularly effective in reducing the response even when the building stiffness changes by plusmn15% using WT for implementation of frequency and is robust; whereas the TMD loses its effectiveness under such building stiffness variations.