DOI QR코드

DOI QR Code

Shaft Group Efficiency of Friction Pile Groups in Deep Soft Clay

대심도 마찰무리말뚝의 주면 무리효율 분석

  • Received : 2011.09.06
  • Accepted : 2011.12.30
  • Published : 2012.04.30

Abstract

In this study, the behaviors of friction pile groups are investigated using 3D finite element (FE) analysis. The emphasis was quantifying on the shear load transfer (f-w) characteristics of pile groups and the shaft group effects. A framework for determining the f-w curve is proposed based on both theoretical analysis and field load test database. Through comparisons with case histories and FE results, it is shown that the proposed f-w curve is capable of predicting the behavior of a friction pile in deep soft clay. Additionally, a numerical analysis that takes into account the group efficiency factors were performed for major parameter on group pile-soil interaction, such as the pile spacing, pile arrangement, soil condition, and location of pile cap. Based on these results, the shaft group efficiency factors were also proposed.

본 연구에서는 국내 지반조건에 적합한 대심도 마찰무리말뚝의 주면하중전이 해석 및 주면 무리효율을 고찰하였으며, 여러 현장재하시험 자료와 3차원 유한요소해석 및 이론적인 방법을 통해 대심도 마찰말뚝의 f-w곡선을 제안하였다. 현장재하시험 사례와의 비교분석 결과, 제안된 해석방법은 기존 f-w곡선에 비해 대심도 마찰말뚝의 거동 및 변형 특성을 적절히 예측함을 알 수 있었다. 또한 마찰무리말뚝의 무리효과 및 무리효율을 정량적으로 평가하기 위하여 말뚝 배열, 간격, 지반조건 및 말뚝캡의 위치에 따른 수치해석을 수행하여 다양한 조건 별 마찰무리말뚝의 주면 무리효율을 제시하였다.

Keywords

References

  1. 고준영, 김영호, 최용규, 정상섬(2010) 현장 계측 사례를 통한 단독 말뚝의 주면마찰력계수($\alpha$, $\beta$ 계수) 역산정, 한국지반공학회 논문집, 한국지반공학회, 제26권, 제11호, pp. 99-110.
  2. 부산광역시청 건설본부(2004) 배수펌프장 건설공사 대안설계 보고서, 부산광역시청.
  3. 설훈일, 정상섬(2007) 현장 말뚝재하시험을 통한 암반에 근입된 현장타설말뚝의 주면마찰력 결정, 한국지반공학회 논문집, 한국지반공학회, 제23권, 제9호, pp. 51-63.
  4. 이수형, 최영석, 정충기, 김명모(2001) 모형 실험을 통한 이층지반에 설치된 연직하중을 받는 무리말뚝의 거동 연구, 대한토목학회 논문집, 대한토목학회, 제21권 제5C호. pp. 91-98.
  5. 이진형, 정상섬(2007) 연약지반에 시공된 Piled Raft 기초의 3차원 거동 분석, 한국지반공학회 논문집, 한국지반공학회, Vol. 23, No. 5, pp. 63-75.
  6. 조재연, 정상섬, 이성준(2010) 말뚝두부조건을 고려한 말뚝지지 전면기초의 최적단면 설계, 한국지반공학회 논문집, 한국지반공학회, Vol. 26, No. 12, pp. 31-40.
  7. 파일테스트(2010) 광양 LNG 지반조사 보고서, 포스코.
  8. Akinsumuru, J. O. (1980) Interaction of piles and cap in piled footing, Journal of the Soil Mechanics and Foundation Division, ASCE, Vol. 106, No. GT 11, pp. 1263-1268.
  9. Alawneh, A. S. (2005) Modelling load displacement response of driven piles in cohesionless soils under tensile loading, Computers and Geotechnics, Vol. 32, No. 7-8, pp. 578-586. https://doi.org/10.1016/j.compgeo.2005.11.003
  10. American Petroleum Institute (1993) Recommended Practice of Planning, Designing, and Construction of Fixed Offshore Platforms, Rep. No. API-RF-2A, Dallas.
  11. Backyong Geotechnical & Construction Engineering (2006) Report of static pile load test, Posco-Samwhan Joint Venture
  12. Berezantsev, V. G., Khrisofpriv, V. S., and Colubkov, V. N. (1961) Load bearing capacity and deformation of piled foundations, 5th International Conference on Soil Mechanics, Vol. 2, pp. 11-15.
  13. Broms, K. F., Amesz, A.W., and Rinck, J. (1969) The Negative Skin Friction Along the Shaft of a Foundation Pile, Proc. Proceedings, 7th International Conference on Soil Mechanics And Foundation Engineering, Mexico City, Specialty Session 8.
  14. Briaud, J. L. (1997) Bitumen Selection for Reduction of Downdrag on Piles. Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 123, No. 12, pp. 1127-1134. https://doi.org/10.1061/(ASCE)1090-0241(1997)123:12(1127)
  15. Castelli, F., Maugeri, M., and Motta, E. (1992) Analysis Non Lineare del cedimento di un Palo Singolo, Rivista Italiana di Geotechnica, Vol. 26, No. 2, pp. 115-135.
  16. Combarieu, O. (1985) Frottement Negative sur les pieus, Rapport de recherche LPCN 136, Laboratoire Centrale des ponts Et Chaussees, 151.
  17. Fan, C. C. and Long, J. h. (2005) Assessment of Existing Methods for Predicting Soil Response of Laterally Loaded Piles in Sand, Computers and Geotechnics, Vol. 32, No. 4, pp. 274-289. https://doi.org/10.1016/j.compgeo.2005.02.004
  18. Hansbo, S. (1993) Interaction problems related to installation of pile groups, 1st International Geotechnical Seminar on Deep Foundations on Bored and Auger Piles, pp. 59-66.
  19. Horikoshi, K. and Randolph, M. F. (1996) Centrifuge modeling of piled raft foundations on clay, Geotechnique, Vol. 46, No. 4, pp. 741-752. https://doi.org/10.1680/geot.1996.46.4.741
  20. Jeong, S. S. and Cho, J. Y. (2010) The settlement behavior of plied raft subjected to vertical load, International Journal of Geo-Engineering, Vol. 2, No. 3, pp. 5-10.
  21. Katzenbach, R., Arslan, U. and Moormann, C. (2000) Piled raft foundation projects in Genrmany. Design applications of raft foundation, pp. 323-391.
  22. Kim, Y.H. and Jeong, S.S. (2011) Analysis of soil resistance on laterally loaded piles based on 3D soil-pile interaction, Computers and Geothechnics, Vol. 38, No. 2, pp. 248-257. https://doi.org/10.1016/j.compgeo.2010.12.001
  23. Koizumi, Y. and Ito, K. (1967) Field tests with regard to pile driving and bearing capacity of piled foundations, Soils and Foundations, Vol. 7, No. 3.
  24. Liu, J. L., Huang, Q., Li, H., Li, X. and Hu, W. L. (1994) Experimental research on bearing behavior of pile groups in soft soil, 12th International Conference in Soil Mechanics and Foundation Engineering, Vol. 2, pp. 535-538.
  25. McVay, M. C., O'Brien, M., Townsend, F. C., Bloomquist, D. G., and Caliendo, J. A. (1989) Numerical analysis of vertically loaded pile groups. Proceedings of Foundation Engineering Congress, ASCE, Northwestern University, pp. 675-690.
  26. O'Neill, M. W. (1983) Group action in offshore piles, Geotechnical Practice in Offshore Engineering, pp. 25-64.
  27. Phung, D. L. (1993) Footing with settlement-reducing piles in noncohesive soil, Ph D Dissertation, Department of geotechnical engineering, Chalmers University of Technology.
  28. PLAXIS 3D Foundation (2008) PLAXIS 3D foundation user manual, Version 2.1, Brinkgreve, R. B. and Swolfs, W. M., PLAXIS Inc.
  29. Randolph, M. F. and Wroth, C. P. (1978) Analysis of deformation of vertically loaded piles, Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 104, No. GT12, pp. 1465-1488.
  30. Sayed, S. M. and Bakeer, R. M. (1992) Efficiency formula for pile groups, Journal of the Geotechnical Engineering, Vol. 118, No. 2, pp. 278-299. https://doi.org/10.1061/(ASCE)0733-9410(1992)118:2(278)
  31. Seed, H. b. and Reese, L. C. (1957) The action of soft clay along friction piles. Transactions, ASCE, Vol. 122
  32. Seol, H. I., Jeong, S. S., and Cho, S. H. (2009) Analytical method for load-transfer characteristics of rock-socketed drilled shafts. Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 135, No. 6, pp. 778-789. https://doi.org/10.1061/(ASCE)1090-0241(2009)135:6(778)
  33. Terzaghi, K. and Peck, R. B. (1967) Settlement of Point Bearing Pile Foundation: Settlement of Floating Pile Foundation, Soil Mechanics in Engineering Practice, 2nd edition, John Wiley & Sons, New York.
  34. Vesic, A. S. (1969) Experiment with instrumented pile groups in sand, ASTM Special Technical Publication, No. 444, pp. 172- 222.
  35. Wallace, J. W., Fox, P. J., and Stewart, J. P. (2002) Cyclic Large Deflection Testing of Shaft Bridges Part II: Analytical Studies. Rep. No. 59A0183, California Dept. of Transportation. California.
  36. Zhang, Q. Q., Zhang, Z. M., and He, J. Y. (2010) A simplified approach for settlement analysis of single pile and pile groups considering interaction between identical piles in multilayered soils, Computers and Geotechnics, Vol. 37, No. 8, pp. 969-976. https://doi.org/10.1016/j.compgeo.2010.08.003