Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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A Study on Reliquefaction Behavior of Railway Embankment Using 1g Shaking Table Test

1g 진동대 실험을 이용한 철도 제방의 재액상화 거동 연구

  • Chae, Minhwan (Advanced Infrastructure Research Team of Korea Railroad Research Institute) ;
  • Yoo, Mintaek (Railroad Structure Research Team, Korea Railroad Research Institute) ;
  • Lee, Il-Wha (Advanced Infrastructure Research Team of Korea Railroad Research Institute) ;
  • Lee, Myungjae (Railroad Structure Research Team, Korea Railroad Research Institute)
  • 채민환 (한국철도기술연구원 첨단인프라융합연구실) ;
  • 유민택 (한국철도기술연구원 철도구조연구실) ;
  • 이일화 (한국철도기술연구원 첨단인프라융합연구실) ;
  • 이명재 (한국철도기술연구원 철도구조연구실)
  • Received : 2021.10.21
  • Accepted : 2021.11.01
  • Published : 2021.11.30
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Abstract

The purpose of this study is liquefaction phenomenon was simulated using the 1g shaking table test. Analysis of liquefaction and Re-liquefaction behavior according to the ground conditions was analyzed when an embankment exists above the ground. The soil used in the experiment was silica sand and the ground composition was a liquefied layer of 50cm (Case 1), a non-liquefied layer of 17.5cm and a liquefied layer of 32.5cm (Case 2). The embankment was formed by fixing the height of 10cm and the slope of the slope at a ratio of 1:1.8. For seismic waves, excitation of a 5Hz sine wave was performed for 8 seconds, and a total of 5 case excitations were performed. In Case 1, it was confirmed that liquefaction occurred at all depths during the first vibration excitation at the free-field and that liquefaction did not occur at all depths except 5cm at the third vibration excitation. At the center of the embankment, liquefaction occurred up to a depth of 20cm during the first vibration excitation, and it was confirmed that liquefaction did not occur at all depths except for a depth of 5cm during the second vibration excitation.

본 연구는 액상화 현상을 모사할 수 있는 1g 진동대 실험(Shaking table test)을 이용하여 포화 사질토 지반 위 제방 존재 유무에 따른 지반 조건 대상으로 재액상화 거동에 대하여 연구하였다. 실험에 사용된 지반은 실리카 모래를 사용하였으며, 지반조성은 액상화층 50cm(Case 1)와 비액상화층 17.5cm와 액상화층 32.5cm인 경우(Case 2)로 2가지 조건으로 수중낙사법을 이용하여 조성하였다. 제방은 높이 10cm, 사면 기울기는 1 : 1.8 비율로 고정하여 조성하였다. 지진파는 5Hz의 정현파를 8초간 가진을 진행하여 총 1차부터 5차 가진을 수행하였다. Case 1의 경우 자유장 위치에서 1차 가진 시 모든 깊이에 액상화가 발생하였으며, 3차 가진 시 5cm 깊이를 제외한 모든 깊이에서 액상화 현상이 발생하지 않음을 확인하였다. 제방 중심 위치에서는 1차 가진 시 20cm 깊이까지 액상화가 발생하였으며, 2차 가진 시 5cm 깊이를 제외한 모든 깊이에서 액상화 현상이 발생하지 않음을 확인하여, 제방 구조물 설치 시 재액상화 거동에 대하여 평가하였다.

Keywords

Acknowledgement

본 연구는 국토교통부/국토교통과학기술진흥원의 지원으로 수행되었습니다(21SCIP-C155167-03: MT21027).

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