The seismic deformation method is conventionally used as a seismic design for a multi-utility tunnel in Korea. In the seismic deformation method, the soil ground’s natural period is one of the most critical factors for calculating the ground displacement using cosine functions. Correction factors for the natural period and shear wave velocity have been used to consider the non-linearity of dynamic soil properties. However, the correction factors have been issued because the correction factors have not been sufficiently studied to consider Korea’s regional conditions. This paper aims to evaluate the natural periods for the seismic deformation method considering Korea’s ground conditions. Ground response analysis was performed using seven real earthquake records on twelve sites with different soil conditions where actual multi-utility tunnels are installed. As a result, natural periods of the sites were analyzed and new correction factors were proposed according to seismic performance and Korea’s regional conditions.

A B S T R A C T
1. 서 론
2. 문헌연구
    2.1 국내 연구 사례
    2.2 고유주기에 대한 일본 및 국내 기준 연구
3. 지반응답해석
    3.1 대상부지
    3.2 설계지반운동 수준 및 입력지진기록 선정
    3.3 흙의 비선형 동적 변형특성
    3.4 해석 조건
4. 지반응답해석 결과
    4.1 붕괴방지수준(Collapse prevention performance level, CLE)
    4.2 기능수행수준(Operational performance level, OLE)
    4.3 지반특성에 따른 분석
    4.4 보정계수의 개선
    4.5 전단파속도 감소계수(C)
5. 결 론
REFERENCES

• 최정호(공주대학교 건설환경공학과) | Choi Jeong Ho (Department of Civil & Environmental Engineering, Kongju National University)
• 윤종석(공주대학교 건설환경공학과) | Yun Jong Seok (Department of Civil & Environmental Engineering, Kongju National University)
• 추연욱(공주대학교 건설환경공학부) | Choo Yun Wook (Department of Civil & Environmental Engineering, Kongju National University) Corresponding author
• 윤준웅(한국시설안전공단 국가내진센터) | Youn Jun Ung (National Center for Seismic Safety, KISTEC)