All Issue

2026 Vol.27, Issue 4 Preview Page
Analysis of the Liquefaction-Induced Settlement Characteristics According to the Embedded Depth Ratio of Sheet Piles Adjacent to Existing Structures

기존 구조물에 인접한 시트파일의 근입비에 따른 액상화 침하 특성 분석

Joohyun Lee1
,
Sanghoon Kim1
,
Jongchan Yoon1
,
Donghun Lee1
,
Suwon Son1
,
Jinman Kim2*
이 주현1
,
김 상훈1
,
윤 종찬1
,
이 동훈1
,
손 수원1
,
김 진만2*
1Ph.D Student, Department of Civil Engineering, Pusan National University
2Professor, Department of Civil Engineering, Pusan National University
*Corresponding Author
1 April 2026. pp. 45-54
PDF XML Citation
Abstract

Liquefaction induced by earthquakes is widely recognized as one of the major causes of structural settlement and foundation instability in saturated sandy soils. Liquefaction can cause severe structural damage, such as settlement, differential settlement, and tilting of structures, and may ultimately lead to the functional failure of urban infrastructure. Most existing liquefaction mitigation techniques have been developed for newly constructed structures or sites with sufficient construction space, which limits their applicability in densely built-up areas containing existing structures. In this study, a 1-G shaking table model test was conducted to analyze the settlement behavior according to the embedded depth ratio of sheet piles installed adjacent to an existing structure, with particular consideration of their applicability to existing structures. The model ground was prepared using Jumunjin standard sand, with the liquefiable layer formed at a relative density of 45% and the non-liquefiable layer at a relative density of 85 %. A 1/50-scale model was constructed based on the similitude law proposed by Iai (1989), and a sinusoidal input motion with an acceleration of 0.6 g and a frequency of 10 Hz was applied. The embedded depth ratio (EDR) of the sheet pile was subdivided into seven levels ranging from 0.55 to 0.85. The experimental results showed that the installation of the sheet pile reduced the structural settlement by up to approximately 67 % compared with the unreinforced condition. In addition, the settlement reduction effect increased with increasing EDR, although the decrease in settlement tended to converge at EDR values greater than 0.8. The difference in settlement according to the presence or absence of a setback distance between the structure and the sheet pile was approximately 2 %, indicating that embedment depth, rather than setback distance, is the dominant design parameter governing liquefaction damage mitigation performance. The findings of this study are expected to provide practical basic data for the design of liquefaction mitigation measures around existing structures.

Keywords
Liquefaction
Earthquake
Sheet pile
Embedded depth ratio
Existing structure
Settlement

지진 시 발생하는 액상화 현상은 포화된 사질토 지반에서 구조물 침하 및 기초 불안정성을 유발하는 주요 원인 중 하나로 알려져 있다. 액상화는 구조물 침하, 부등침하 및 전도와 같은 심각한 구조적 피해를 야기하며, 도시 기반시설의 기능 상실로 이어질 수 있다. 기존 액상화 피해 저감 기술은 대부분 신규 구조물이나 광범위한 시공 공간을 필요로 하는 현장을 대상으로 개발되어, 기존 구조물이 밀집된 지역에서는 적용이 제한되는 문제점을 가진다. 본 연구에서는 기존 구조물에 인접하여 설치된 시트파일의 근입비 변화에 따른 구조물 침하 거동을 분석하기 위하여 1-G 진동대 모형실험을 수행하였다. 모형지반은 주문진 표준사를 사용하여 조성하였으며, 액상화층은 상대밀도 45 %, 비액상화층은 상대밀도 85 %로 구성하였다. Iai(1989)의 상사법칙을 적용하여 1/50 축척 모델을 제작하였고, 입력파는 가속도 0.6 g, 주파수 10 Hz의 정현파를 적용하였다. 시트파일 근입비(EDR)는 0.55~0.85 범위에서 7단계로 세분화하였다. 실험 결과, 시트파일 설치 시 구조물 침하량은 비보강 조건 대비 최대 약 67 % 감소하였다. 또한 근입비 증가에 따라 침하 감소 효과는 증가하였으나, EDR 0.8 이상에서는 침하량 감소가 수렴하는 경향을 나타냈다. 구조물과 시트파일의 이격거리 유무에 따른 침하량 차이는 약 2 % 수준으로 나타나, 액상화 피해 저감 성능에 있어 이격거리보다 근입깊이가 지배적인 설계 변수임을 확인하였다. 본 연구 결과는 기존 구조물 주변 액상화 저감 설계 시 적용 가능한 실무적 기초자료로 활용될 수 있을 것으로 기대된다.

키워드
액상화
지진
시트파일
근입비
기존 구조물
침하
References
1

Alam, M. and Motamed, R. (2024), Behavior of impermeable and permeable sheet piles under liquefaction-induced foundation settlement, Soil Dynamics and Earthquake Engineering, Vol. 176, 108184.

2

Boulanger, R.W. and Idriss, I.M. (2014), CPT and SPT based liquefaction triggering procedures, Earthquake Spectra, Vol. 30, No. 3, pp. 1037~1063.

3

Cubrinovski, M., Bray, J.D., Taylor, M., Giorgini, S., Bradley, B., Wotherspoon, L. and Zupan, J. (2011), Liquefaction impacts in the central business district during the 2010-2011 Christchurch earthquakes, Proceedings of the New Zealand Society for Earthquake Engineering, pp. 1~8.

10.1785/gssrl.82.6.893
4

Idriss, I.M. and Boulanger, R.W. (2008), Soil Liquefaction During Earthquakes, Earthquake Engineering Research Institute (EERI), Oakland, California, USA.

5

Iai, S. (1989), Similitude for shaking table tests on soil–structure–fluid model in 1g gravitational field, Soil and Foundations, Vol. 29, No. 1, pp. 105~118.

10.3208/sandf1972.29.105
6

Ishihara, K. (1996), Soil Behaviour in Earthquake Geotechnics, Oxford University Press, Oxford, UK.

10.1093/oso/9780198562245.001.0001
7

Ishihara, K. (1998), Liquefaction and flow failure during earthquakes, Géotechnique, Vol. 48, No. 2, pp. 157~184.

8

Jeon, J.S., Kim, D.S. and Kim, M.M. (2010), Model testing of soil–structure interaction during liquefaction, Soil Dynamics and Earthquake Engineering, Vol. 30, No. 11, pp. 1341~1353.

9

Kaneko, T. and Yasuda, S. (2014), Model tests on effectiveness of sheet pile walls for mitigating liquefaction-induced settlement, Soils and Foundations, Vol. 54, No. 3, pp. 451~463.

10

Korea Meteorological Administration (2024), Earthquake statistics and seismic records in Korea, Korea Meteorological Administration, Seoul, Korea.

11

Kramer, S.L. (1996), Geotechnical Earthquake Engineering, Prentice Hall, New Jersey, USA.

12

Liu, X., Yang, J. and Wang, G. (2023), Long-term response of granular materials subjected to repetitive mechanical loads: Engineering implications, Geomechanics and Engineering, Vol. 42, No. 6, pp. 453~462.

13

Ministry of the Interior and Safety (2018), Pohang Earthquake White Paper, Ministry of the Interior and Safety, Seoul, Korea.

14

Motohashi, K., Yasuda, S. and Nagase, H. (2011), Shaking table tests on settlement reduction of existing structures using sheet pile walls during liquefaction, Soils and Foundations, Vol. 51, No. 2, pp. 237~246.

15

Nguyen, V.T., O’Sullivan, C., Coop, M.R. and Jardine, R.J. (2021), Coarse-fine mixtures subjected to repetitive Ko loading: Effects of fines fraction, particle shape, and size ratio, Powder Technology, Vol. 377, pp. 575~584.

10.1016/j.powtec.2020.09.017
16

Seed, H.B. and Idriss, I.M. (1971), Simplified procedure for evaluating soil liquefaction potential, Journal of the Soil Mechanics and Foundations Division, ASCE, Vol. 97, No. SM9, pp. 1249~1273.

10.1061/JSFEAQ.0001662
17

Tokimatsu, K. and Seed, H.B. (1987), Evaluation of settlements in sands due to earthquake shaking, Journal of Geotechnical Engineering, ASCE, Vol. 113, No. 8, pp. 861~878.

10.1061/(ASCE)0733-9410(1987)113:8(861)
18

United States Geological Survey (USGS) (2023), Earthquake hazards program and global seismicity statistics, United States Geological Survey.

19

Yasuda, S. and Ishihara, K. (1997), Lateral spreading in liquefied ground during earthquakes, Soils and Foundations, Vol. 37, No. 3, pp. 73~84.

20

Yoon, J.C. (2023), Experimental study on liquefaction 0damage mitigation using sheet piles with varying embedment ratios, Journal of the Korean Geotechnical Society, Vol. 39, No. 5, pp. 45~56 (in Korean).

21

Youd, T.L., Idriss, I.M., Andrus, R.D., Arango, I., Castro, G., Christian, J.T., Dobry, R., Finn, W.D.L., Harder Jr., L.F., Hynes, M.E., Ishihara, K., Koester, J.P., Liao, S.S.C., Marcuson III, W.F., Martin, G.R., Mitchell, J.K., Moriwaki, Y., Power, M.S., Robertson, P.K., Seed, R.B. and Stokoe II, K.H. (2001), Liquefaction resistance of soils: Summary report from the 1996 NCEER and 1998 NCEER/NSF workshops on evaluation of liquefaction resistance of soils, Journal of Geotechnical and Geoenvironmental Engineering, Vol. 127, No. 10, pp. 817~833.

10.1061/(ASCE)1090-0241(2001)127:10(817)
Information
  • Publisher :Korean Geo-Environmental Society
  • Publisher(Ko) :한국지반환경공학회
  • Journal Title :Journal of the Korean Geo-Environmental Society
  • Journal Title(Ko) :한국지반환경공학회 논문집
  • Volume : 27
  • No :4
  • Pages :45-54
  • Received Date : 2026-03-06
  • Revised Date : 2026-03-09
  • Accepted Date : 2026-03-24
  • DOI :https://doi.org/10.14481/jkges.2026.27.4.45
Journal Informaiton Journal of the Korean Geo-Environmental Society Journal of the Korean Geo-Environmental Society
Online Submission
  • NRF
  • KOFST
  • KISTI Current Status
  • KISTI Cited-by
  • orcid
Journal Informaiton Journal Informaiton - close