地震波基线漂移校正及结构地震响应分析

Baseline drift correction of seismic wave and response analysis of the structure earthquake

针对实际地震动采集过程中由于低频噪声、速度和加速度初始值以及人为操作误差等诸多影响因素造成地震波位移时程曲线出现严重基线漂移的问题,以地震波基线漂移校正为目标,在Iwan法和EMD法的基础上,提出了一种新的基线漂移处理方法。该方法可以保留原始记录的峰值和频谱特性,保证了基线漂移处理后的速度终点值为零,位移终点值平行于时间轴。在文中方法的基础上应用ANSYS结合"大质量法"和"位移法"进行了地震响应动力计算。结果表明:采用文中提出的基线漂移处理方法可以保证在不改变原始记录峰值及频谱特性的基础上,对地震波基线漂移现象进行校正。研究成果对低频噪声、初始值及人为操作误差等因素引起的基漂现象滤除具有参考价值。

Due to the influence of many factors in the actual seismic acquisition process such as the low frequency noise,initial velocity and acceleration,and human operation error,serious baseline drift occurs in the seismic wave displacement time history curve.Therefore,the acceleration record needs to be corrected in the process of structure earthquake response analysis.Based on the method of Iwan and EMD,a new method is proposed to deal with the baseline drift of seismic wave.The new method retained the characteristics of initial record,such as acceleration peak and frequency features,and can remove the baseline drifts of velocity and displacement curves.The seismic dynamic response of the earthquake was calculated using the ANSYS combined with'large mass method'and'displacement method'based on the new method mentioned above.The results showed that the baseline drift processing method proposed in this paper can ensure the correction of the baseline drift of seismic waves better without changing the peak and spectrum characteristics of the original records.The research results have guiding significance for filtering bleaching phenomenon caused by low frequency noise,initial value and artificial operation error.