Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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A Study on Bearing Capacity Reinforcement for PHC Pile Foundation Using Post-grouting

그라우팅 기법을 활용한 PHC 파일 기초의 지지력 증강 효과 연구

  • Yoo, Min-Taek (High-speed Railroad Systems Research Center, Korea Railroad Research Institute) ;
  • Lee, Su-Hyung (Urban Railroad Research Team, Korea Railroad Research Institute) ;
  • Kim, Seok-Jung (Geotechnical Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology) ;
  • Choi, Yeong-Tae (High-speed Railroad Systems Research Center, Korea Railroad Research Institute) ;
  • Park, Jeongjun (High-speed Railroad Systems Research Center, Korea Railroad Research Institute)
  • 유민택 (한국철도기술연구원 첨단인프라연구팀) ;
  • 이수형 (한국철도기술연구원 도시교통실용화연구팀) ;
  • 김석중 (한국건설기술연구원 지반연구소) ;
  • 최영태 (한국철도기술연구원 첨단인프라연구팀) ;
  • 박정준 (한국철도기술연구원 첨단인프라연구팀)
  • Received : 2016.12.21
  • Accepted : 2017.06.14
  • Published : 2017.06.30
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Abstract

In this research, post grouting methods were applied on PHC piles, and static load tests were conducted to confirm the effect of post grouting on bearing capacity enhancement of PHC piles. Grouting pressures of 1.9 MPa and 3.5 MPa were applied, and bearing capacities of grouted piles were compared with that of non-grouted pile. From the static load test results, the bearing capacities of grouted piles were about 3 times higher than that of non-grouted pile. In addition, the design efficiency (allowable bearing capacity/nominal bearing capacity) increased from 32% to 97% after post grouting, and the axial stiffness of piles also increased by about 1.3 times per grouting pressure.

본 연구에서는 매입식 PHC 기성말뚝에 대한 포스트 그라우팅 공법을 적용하고, 정재하 실험을 수행하여 포스트그라우팅 공법의 지지력 증강효과를 확인하였다. 그라우팅 압력은 1.9MPa 및 3.5MPa을 적용하였으며, 그라우팅을 수행하지 않은 미보강 말뚝과의 지지력을 비교하였다. 정재하 실험 결과를 바탕으로 PHC 말뚝의 지지력을 분석한 결과, 말뚝의 항복 하중은 약 3배 이상 증가하였으며 설계효율은 당초 32%에서 97%로 증가하였다. 또한, 그라우팅 공법을 적용한 말뚝의 축방향 강성은 그라우팅 주입압의 약 1.3배 비율로 증가하였다.

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References

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