Earthquake Ground Motion Characteristics as a Function of a Preprocessing Procedure

To enable the engineering application of earthquake ground motion records, this study establishes a standardized preprocessing procedure and systematically analyzes how each preprocessing step affects the characteristics of the ground motion data. Due to recent expansion of seismic networks in South Korea, low- to mid-amplitude seismic ground motions become abundant. However, raw ground motion recordings contain instrument responses and ambient noise and are often affected by baseline drift, which leads to divergence in the integrated displacement time histories. Therefore, reliable use of these records in engineering analysis requires a comprehensive preprocessing procedure that includes instrument response correction, signal windowing, filtering, and baseline correction. In this study, we performed a sensitivity analysis on ground motion data recorded in South Korea to quantitatively assess how key preprocessing parameters influence ground motion characteristics. Based on the findings, a standardized preprocessing workflow is proposed to support the effective use of ground motion records in site response analysis, dynamic structural analysis, and seismic hazard assessments.