Appropriate ground motion intensity measures for estimating the earthquake demand of floor acceleration-sensitive elements in super high-rise buildings

Abstract

To characterise the functionality resilience of super high-rise buildings subjected to earthquakes, an investigation is conducted on the selection of appropriate ground motion intensity measures (IMs) for developing an efficient and sufficient correlation with peak floor acceleration (PFA) and floor acceleration response spectrum (FARS) for floor acceleration-sensitive building contents and equipment. The efficiency and sufficiency of 53 collected IMs are assessed with respect to PFA and FARS at selected floors of two example-frame core-tube super high-rise buildings. Two sets of ground motions, i.e. far-field and pulse-type near-field motions, are chosen to reflect the record-to-record variability in the investigation. The investigation indicates that with respect to PFA, the collected IMs can be divided into three different groups based on their efficiency. The ground-acceleration-related IMs, i.e. PGA (peak ground acceleration), EDA (Effective design acceleration) and A95 (threshold of acceleration when 95% of Arias intensity is achieved), are shown to be efficient in either set of ground motions. Regarding FARS, the appropriate IMs are notably different from those in the case of PFA, from the perspective of efficiency as well as sufficiency. None of the collected IMs can maintain its sufficiency with respect to the magnitude and source-to-site distance in any case.