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Cyclic Triaxial Test on Undisturbed Sample in the Fine-Grained Soils that Experienced Ground Settlement by Earthquake Loading and Improving Korean Method for Liquefaction Potential Assessment

지진시 지반침하가 발생한 세립토지반의 불교란시료를 대상으로 한 반복삼축시험의 수행과 국내 액상화 평가법의 제고

  • 최재순 (서경대학교 토목건축공학과) ;
  • 백우현 (서울과학기술대학교 토목공학과) ;
  • 진윤홍 ((주)수성엔지니어링)
  • Received : 2022.09.13
  • Accepted : 2023.11.30
  • Published : 2024.01.01

Abstract

In the case of the Pohang earthquake, which had a magnitude of 5.4 in 2017, geotechnical damages such as liquefaction and ground settlement occurred. The need for countermeasures has emerged, and experimental research in the Pohang area has continued. This study collected undisturbed samples from damaged fine-grained soil areas where ground settlement occurred in Pohang. Cyclic tri-axial tests for identifying the dynamic characteristics of soils were performed on the undisturbed samples, and the results were analyzed to determine the cause of ground settlement. As a result of the study, it was determined that in the case of fine-grained soils, ground settlement occurred because the seismic load as an external force was relatively more significant than the shear resistance of the very soft fine-grained soils, rather than due to an increase in excess pore water pressure.

Keywords

Acknowledgement

본 논문은 행정안전부의 재원으로 국립재난안전연구원의 개발사업에 대한 빅데이터 기반 재해영향 평가기술 개발사업의 지원을 받아 연구되었습니다(RS-2021-ND629011).

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