The site coefficients in the common requirements for seismic design codes, which were promulgated in 2017, were reevaluated and the standard design spectrum for soil sites were newly proposed in order to ensure the consistency of the standard design spectra for rock and soil sites specified in the common requirements. Using the 55 ground motions from domestic and overseas intraplate earthquakes, which were used to derive the standard design spectrum for rock sites, as rock outcropping motions, site response analyses of Korean soil were performed and its ground-motion-amplification was characterized. Then, the site coefficients for soil sites were reevaluated. Compared with the existing site coefficients, the newly proposed short-period site coefficient Fa increased and the long-period site coefficient Fv decreased overall. A new standard design spectrum for soil sites was proposed using the reevaluated site coefficients. When compared with the existing design spectrum, it could be seen that the proposed site coefficients and the standard design spectrum for soil sites were reasonably derived. They reflected the short-period characteristics of earthquake and soil in Korea.

ABSTRACT
 1. 서 론
 2. 내진설계기준 공통적용사항의 현황
 3. 지반증폭계수 Fa와 Fv의 재산정
 4. 토사지반의 표준설계응답스펙트럼
 5. 결 론
 REFERENCES

• 이진호(부경대학교 해양공학과) | Lee Jin Ho (Department of Ocean Engineering, Pukyong National University) Corresponding author
• 김정한(부산대학교 건설융합학부) | Kim Jung Han (School of Urban, Architecture and Civil Engineering, Pusan National University)
• 김재관(前 서울대학교 건설환경공학부) | Kim Jae Kwan (Department Civil and Environmental Engineering, Seoul National University)