Scaling of design earthquake ground motions fortall buildings based on drift and input energy demands

摘要

Rational scaling of design earthquake ground motions for tall buildings is essential for safer,risk-based design of tall buildings. This paper provides the structural designers with an insight for morerational scaling based on drift and input energy demands. Since a resonant sinusoidal motion can be anapproximate critical excitation to elastic and inelastic structures under the constraint of acceleration orvelocity power, a resonant sinusoidal motion with variable period and duration is used as an input waveof the near-field and far-field ground motions. This enables one to understand clearly the relation of theintensity normalization index of ground motion (maximum acceleration, maximum velocity, accelerationpower, velocity power) with the response performance (peak interstory drift, total input energy). It isproved that, when the maximum ground velocity is adopted as the normalization index, the maximuminterstory drift exhibits a stable property irrespective of the number of stories. It is further shown that,when the velocity power is adopted as the normalization index, the total input energy exhibits a stableproperty irrespective of the number of stories. It is finally concluded that the former property on peakdrift can hold for the practical design response spectrum-compatible ground motions.