Enactment of new site classification system and design response spectra as new minimum requirements in Korea

Abstract

Recent studies have shown that the site classification system and site coefficients in the current Korean seismic code is not suitable for representing the ground motions expected in Korea, mainly because of the shallow-bedrock condition of Korean soil sites. A new site classification system and site coefficients were thus proposed, and the provisions were discussed in a public hearing process so that it meets the 'minimum requirements' criteria for general seismic design in Korea. The public hearing process recommended to modify the naming of site classes and adjust the amplification factors so that the level of short-period amplification is suitable for economical seismic design. Finally, the new provisions were found to be more reliable than the current seismic code based on the comparison with 2016 Gyeongju earthquake records.