Predictive equations to quantify the impact of spectral matching on ground motion characteristics

• Published in: Earthquake spectra Vol. 32; no. 1; pp. 125 - 142
• Main Authors: Carlson, Clinton, Zekkos, Dimitrios, Athanasopoulos-Zekkos, Adda
• Format: Journal Article
• Language: English
• Published: London, England Earthquake Engineering Research Institute 01-02-2016; SAGE Publications
• Subjects: Acceleration; civil engineering; Earthquake prediction; Earthquakes; engineering geology; equations; frequency; frequency domain analysis; Ground motion; Matching; Mathematical analysis; mathematical methods; peak ground acceleration; regression analysis; scale factor; Seeds; seismic intensity; seismic response; Seismology; Spectra; statistical analysis; time domain analysis; velocity
• ISSN: 8755-2930; 1944-8201
• DOI: 10.1193/090914EQS140M

Spectral matching, the process of modifying a seed acceleration time history in intensity and frequency content until its acceleration response spectrum matches a target spectrum, is used extensively in practice. Predictive equations that quantify the impact of spectral matching on the peak ground velocity, peak ground displacement, Arias intensity, and cumulative absolute velocity of a scaled seed time history have been developed and validated on the basis of thousands of matched motions, three different earthquake scenarios, and numerous target spectra. It is found that spectral mismatch is the most critical factor affecting the changes in ground motion characteristics. The technique used for modification (e.g., time domain or frequency domain) is in many cases not critical. Based on the results, recommendations in order to minimize the impact of matching on the ground motion characteristics are provided.