Ground Motion Truncation Method Using Time-Frequency Analysis

This study proposes a new ground motion truncation method considering the time-frequency representations of the waveform and the target structure’s modal properties. A new index, Stacked Segment Power Spectral Density, is introduced to identify and remove time segments with little influence on peak structural responses. The segments are removed irrespective of whether they occur in the head or tail of the record, unlike conventional head–tail deletion methods. It is shown through numerical examples of elasto-plastic models that the proposed truncation method enables efficient reduction of the ground motion duration while achieving close agreement in peak responses with the original record.