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2015 Vol.31, Issue 8 Preview Page
Evaluation of Axial Bearing Capacity of Waveform Micropile by Centrifuge Test

원심모형실험을 통한 파형 마이크로파일의 연직 지지력 평가

Young-Eun Jang1
,
Jin-Tae Han2*
,
Jae-Hyun Kim3
,
Heon-Joon Park4
,
Sang-Hwan Kim5
장 영은1
,
한 진태2*
,
김 재현3
,
박 헌준4
,
김 상환5
1Ph.D Student, Dept. of Geospace Engrg., Univ. of Science & Technology
2 Senior Researcher, Dept. of Geotechnical Engrg., Korea Institute of Civil Engrg. and Building Technology (Associated Prof., UST)
3Ph.D Student, Dept. of Civil and Environmental Engrg., KAIST
4Research Prof., Dept. of Civil and Environmental Engrg., KAIST
5Prof., Dept. of Civil Engrg., Hoseo Univ.
1과학기술연합대학원대학교 지반신공간공학과 박사과정
2한국건설기술연구원 지반연구소 수석연구원, UST 부교수
3KAIST, 건설및환경공학과 박사과정
4KAIST, 건설및환경공학과 연구교수
5호서대학교 토목공학과 교수
*교신저자. *Corresponding Author. 
31 August 2015. pp. 39-49
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Abstract

In this study, a series of centrifuge tests were performed in order to observe the bearing capacity of waveform micropile, a new concept of micropile that uses a modified jet grouting process. A total of six models were considered, conventional micropile, jet grouted pile, and four different shapes of waveform micropiles. The test results indicated that the waveform micropile effectively contributes to the increase of the bearing capacity compared to the micropile without the shear keys. Among the waveform micropiles, the model that has a relatively small space between the shear keys showed the most significant improvement of load capacity. Additionally, the ultimate load capacities of all piles were compared using well-known estimation method. As a result, P-S curve method and total settlement method with 25.4 mm were considered suitable to account ultimate load for the waveform micropile.

Keywords
Micropile
Waveform micropile
Jet grouting method
Pile load test
Pile load capacity

본 논문에서는 jet grouting 공법을 적용한 파형 마이크로파일의 지지력 향상 효과 및 거동 특성을 분석하기 위한 연구를 수행하였다. 각 말뚝의 형상에 따른 거동을 비교하기 위해 일반 마이크로파일, 파형이 없는 jet grouted 말뚝 및 네 종류의 파형 마이크로파일의 모델을 제작하여 원심모형실험을 수행하였다. 실험 결과 일반 마이크로파일 대비 파형 마이크로파일의 지지력 향상 효과를 확인 할 수 있었으며, 특히 파형의 간격이 상대적으로 좁은 말뚝의 지지력 개선 효과가 큰 것으로 분석되었다. 또한 기존의 재하시험에 의한 지지력 예측 및 평가 방법을 토대로 파형 마이크로파일의 지지력 산정 방안을 검토한 결과 P-S 곡선법과 25.4mm 전침하량기준이 파형 마이크로파일의 거동을 합리적으로 예측하는 것으로 나타났다.

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Information
  • Publisher :The Korean Geotechnical Society
  • Publisher(Ko) :한국지반공학회
  • Journal Title :Journal of the Korean Geotechnical Society
  • Journal Title(Ko) :한국지반공학회 논문집
  • Volume : 31
  • No :8
  • Pages :39-49
  • Received Date : 2015-05-20
  • Revised Date : 2015-07-09
  • Accepted Date : 2015-08-03
  • DOI :https://doi.org/10.7843/kgs.2015.31.8.39
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