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2026 Vol.36, Issue 1 Preview Page

Research Article

A Study on the Adequacy of Safety Factors for Liquefaction Evaluation in Korea

국내 액상화 평가 안전율 기준의 적정성 검토

Kurie Kim1
,
Hyunjee Lim2
,
Man-Jae Kim3
,
Youngsuk Lee4
,
Moon Son5*
김 규리1
,
임 현지2
,
김 만재3
,
이 영석4
,
손 문5*
1Master’s Student, Department of Geological Sciences, Pusan National University
2Researcher, Policy Research Division, Busan Institute of Science & Technology and Higher Education Promotion
3Senior Researcher, Institute of Geohazard Research, Pusan National University
4Researcher, Center for Disaster Management, The Seoul Institute
5Professor, Department of Geological Sciences, Pusan National University
1부산대학교 지질환경과학과 석사과정
2부산과학기술고등교육진흥원 정책연구본부 연구원
3부산대학교 지질재해연구소 전임연구원
4서울연구원 재난안전연구센터 연구원
5부산대학교 지질환경과학과 교수
*Corresponding Author
31 March 2026. pp. 45-59
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Abstract

The 2017 Pohang Earthquake (Mw 5.4) marked the first observation of liquefaction in Korea, prompting a revision of domestic liquefaction evaluation standards. Prior to the earthquake, a factor of safety (FS) of 1.5 was applied in accordance with Foundation Design Criteria (2016); however, the standard was subsequently revised under General Seismic Design (2018), lowering the FS to 1.0, which is currently in use. We examined the appropriateness of domestic liquefaction evaluation standards by applying the criteria from both 2016 and 2018 to Seoul comparing the results. The evaluation was performed using the FS and the Liquefaction Potential Index (LPI). We identified limitations in the ability of both standards to accurately reflect ground conditions. To mitigate these issues, we used different FS criteria and analyzed the spatial consistency between FS-based results and the LPI distribution. Our analysis shows that an FS of 1.1 yielded the highest spatial agreement with LPI; Consequently, we proposes an FS of 1.1 as a more rational standard for liquefaction evaluation.

Keywords
Pohang Earthquake
liquefaction
liquefaction assessment
liquefaction evaluation criteria
factor of safety (FS)
Liquefaction Potential Index (LPI)

2017년 포항지진(Mw 5.4) 당시 국내 최초로 액상화 현상이 관측됨에 따라, 국내 액상화 평가기준이 개정되었다. 포항지진 이전에는 구조물기초설계기준(2016)에 따라 안전율(factor of safety, FS) 1.5가 적용되었으나, 이후 개정된 내진설계일반(2018)에서는 안전율 1.0으로 변경되어 현재까지 적용되고 있다. 이번 연구는 구조물기초설계기준(2016)과 내진설계일반(2018)에 제시된 평가기준을 적용하여 액상화 평가를 수행하고, 그 결과를 비교·분석함으로써 국내 액상화 평가기준의 적정성을 검토하고자 하였다. 액상화 평가는 안전율과 액상화 가능지수(Liquefaction Potential Index, LPI)를 활용하여 수행하였다. 분석 결과, 기존 및 개정 기준 모두 연구지역의 지반 조건을 충분히 반영하지 못하는 한계가 확인되었다. 이러한 한계를 보완하기 위해 안전율 기준을 세분화하고, 각 안전율에 따라 도출된 결과와 액상화 가능지수 분포 간의 공간적 일치도를 비교·분석하였다. 분석 결과, 안전율 1.1에서 안전율 기반 평가와 액상화 가능지수 간의 공간적 일치도가 가장 높게 나타났으며, 이는 연구지역인 서울의 지반 조건을 합리적으로 반영하는 것으로 판단된다. 따라서 연구지역의 지반 특성을 고려한 새로운 액상화 평가기준 안전율 1.1을 제안한다.

키워드
포항지진
액상화
액상화 평가
액상화 평가기준
안전율(FS)
액상화 가능지수(LPI)
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Information
  • Publisher :Korean Society of Engineering Geology
  • Publisher(Ko) :대한지질공학회
  • Journal Title :The Journal of Engineering Geology
  • Journal Title(Ko) :지질공학
  • Volume : 36
  • No :1
  • Pages :45-59
  • Received Date : 2026-01-06
  • Revised Date : 2026-02-20
  • Accepted Date : 2026-02-25
  • DOI :https://doi.org/10.9720/kseg.2026.1.045
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