Identification of Far-Field Long-Period Ground Motions Using Phase Derivatives

Figure 8

Six samples of the positive records. To better understand the effects of later-arriving amplitudes on long-period properties, each record has three subplots, including velocity-time history, velocity response spectrum, and envelope delay. A truncated wave is obtained in the light of envelope delays (detailed operations noted in this text) and the complete record represents the original record without removing the truncated wave. The records from (a) OSKH02NS, Western Tottori, M7.3; (b) HKD178NS, Tokachi Aftershock, M7.1; (c) HKD181NS, Tokachi Mainshock, M8; (d) OSK008NS, Southeast of Kii peninsula, M7.4; (e) TKY024EW, Tohuku, M9; (f) CHB009EW, Tohuku, M9.

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