【摘要】 近场地震动中速度脉冲周期的确定受高频成分的影响具有很强的不确定性。为消除高频成分的影响,假设脉冲幅值恒等于地震动峰值速度,采用简化的脉冲数学模型对地震动速度时程进行最小二乘拟合,得到能够反映原速度时程中主脉冲特性的简化脉冲时程,对该简化脉冲时程应用"峰点法"确定其脉冲周期。最后,对该方法与国际通用的谱速度峰值法和Baker方法进行了比较。分析表明,该法与谱速度峰值法所得结果较为接近,个别情况下,其较后者更为有效。更多还原

【Abstract】 One significant feature that distinguishes near-fault pulse-like ground motions from their counterparts is the presence of one or several dominant pulses typically observed in their velocity time histories.Due to the influence from high frequency contents,calculation of the pulse period involves great uncertainty.Under the assumption that pulse amplitude normally equals the peak ground velocity(PGV) and based on one simplified pulse model,the velocity pulse has been extracted from the original record by means of the least square fitting.Finally,determination of the pulse period is realized by the ‘peak point method’,and efficiency of the proposed method is confirmed after comparing with two existing approaches.更多还原