Eliminating Beating Effects in Damping Estimation of High-Rise Buildings

The beating phenomenon, induced by coupling between translational modes of tall buildings with closely spaced frequencies, may have significant effects on modal identification, especially damping estimation. This paper proposes a new method for attenuating the adverse effects of beating on modal identification for high-rise buildings. Beating in typhoon-induced responses of a high-rise building is clearly observed via both frequency domain and time domain analysis. To eliminate the effects of beating on structural modal identification, a normal coordinates-based modal decomposition method for coupled translational modes is proposed, which is proved to be effective for separating closely coupled translational modes and thereby improving the accuracy of damping estimation for high-rise buildings. This paper aims to provide valuable implications for damping evaluation of high-rise buildings. (C) 2019 American Society of Civil Engineers.