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Summary This study proposes an improved energy‐based approach for quantitative classification of velocity‐pulse‐like ground motions. The pulse amplitude is determined, in its value and in time location, by the amplitude of the half‐cycle pulse having the largest seismic energy. After conducting statistical analyses, a newly‐determined threshold level for selecting pulse‐like ground motions is derived; and then what followed is a comparison analysis of three pulse‐detecting schemes, one using the wavelet analysis, the other two using the energy concept. It is believed that other than providing a useful way of classifying pulse‐like ground motions for structural demand analysis, knowledge of this work could also benefit the development of the ground motion prediction equations accounting for pulse effects, and further to aid the probabilistic seismic hazard analysis in a near‐fault environment. Copyright © 2016 John Wiley & Sons, Ltd.

Near-fault pulse-like ground motions have long been known to be capable of inducing significant seismic damages to the building structures. Reasonable classification of such ground motions has been a challenge to earthquake engineers. This study serves to propose an energy-based approach that can be used to identify those ground motions with dominant pulses observed in the velocity time series; and time integral of the squared ground velocity is employed to represent the motion energy. For removing the influence of high-frequency contents, the potential velocity pulse is first extracted with a pulse model. The starting and ending time points as well as period of the velocity pulse are subsequently determined by the peak-point method. Records with peak ground velocities above 30 cm=s from a database containing more than 3600 recorded ground motions are selected and utilized to calibrate the final criterion. It is concluded that those ground motions whose dominant velocity pulses hold relative energy values of greater than 0.3 can be satisfactorily classified as pulse-like. The proposed approach is further used to identify pulse-like features in arbitrary orientations and pulse-like ground motions possibly caused by forward-directivity effects.Online Material: Tables identifying ground motions with near-fault pulse-like behavior.

a b s t r a c tNumerical simulation has increasingly become an effective method and powerful tool for performancebased earthquake engineering research. Amongst the existing research efforts, most numerical analyses were conducted using general-purpose commercial software, which to some extent limits in-depth investigations on specific topics with complicated nature. In consequence, this work develops a new shear wall element model and associated material constitutive models based on the open source finite element (FE) code OpenSees, in order to perform nonlinear seismic analyses of high-rise RC frame-core tube structures. A series of shear walls, a 141.8-m frame-core tube building and a super-tall building (the Shanghai Tower, with a height of 632 m) are simulated. The rationality and reliability of the proposed element model and analysis method are validated through comparison with the available experimental data as well as the analytical results of a well validated commercial FE code. The research outcome will assist in providing a useful reference and an effective tool for further numerical analysis of the seismic behavior of tall and super-tall buildings.