A Spectral-Acceleration-Based Linear Combination-Type Earthquake Intensity Measure for High-Rise Buildings

With the consideration of higher modes, an attempt is made to develop a spectral-acceleration-based linear combination-type earthquake intensity measure (IM) for high-rise buildings. The modal mass participation factors are determined to take weighting coefficients. A parametric analysis on the correlation between IM and the maximum interstory drift that utilizes the bend-shear coupled continuum model yields a bilinear relationship between the optimal number of modes involved and structural fundamental period. The proposed IM and several other combination-type IMs are shown to be efficient and sufficient, while the scaling robustness of the proposed IM is more stable compared with that of fundamental-mode-based IMs.