Near-fault pulse-like ground motion identification method based on non-causal filtering and zero- point method

Here，based on Butterworth non-causal low-pass filter and the zero-point method，pulse signals in time history of ground motion velocity were extracted，and the cut-off frequency of the filter was determined with the number of extreme value points in pulse signals. 666 near-fault seismic records with their peak velocities larger than 30 cm/s were selected as training data，and the relative energy and amplitude of pulse signals were taken as quantitative indexes to give identification standards of single-pulse and double-pulse ground motions. A pulse period calculation method according to the duration of the most significant pulse signal was also proposed. Comparing the proposed method with the existing methods showed that the pulse extraction method based on Butterworth non-causal low-pass filter and the zero-point method has a better fitting effect，and can be used to extract asymmetric pulse signals and double-pulse signals ； the proposed quantitative identification standards can effectively identify single-pulse and double-pulse ground motions ； the proposed pulse period calculation method can be used to determine pulse periods of single-pulse and double-pulse ground motions. © 2022 Chinese Vibration Engineering Society. All rights reserved.