KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
권호 표지
DOI QR코드

DOI QR Code

Proposed Optimized Column-pile Diameter Ratio with Varying Cross-section for Bent Pile Structures

단일 현장타설말뚝의 변단면 분석을 통한 최적 기둥-말뚝 직경비 제안

  • 김재영 (연세대학교 사회환경시스템공학부) ;
  • 정상섬 (연세대학교 사회환경시스템공학부) ;
  • 안상용 ((주)포스코엔지니어링 인프라사업본부)
  • Received : 2013.05.21
  • Accepted : 2013.08.07
  • Published : 2013.09.30
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, the behavior characteristics of bent pile structures with varying cross-section was examined through the measured results of field load test. A framework for determining the bending stress is calculated based on the stresses in the circumference of the pile using 3D finite element analysis. It is found that the bending stress near the pile-column joint changes rapidly and fracture zones occurs easily at variable cross-sections in bent pile structures. Also, the optimized column-pile diameter ratio was analyzed through the relationship between the column-pile diameter ratio and lateral crack load ratio. Based on this study, the optimized column-pile diameter ratio can be obtained near the inflection point of the curve between the column-pile diameter ratio and lateral crack load ratio. Therefore, a present study by considering the optimized variable cross-section condition would be improved bent pile structures design.

본 연구에서는 변단면 단일 현장타설말뚝의 거동 특성을 평가하고자 현장재하시험 사례를 분석하였으며, 또한 3차원 유한요소해석을 이용하여 말뚝 내부에서 발생하는 응력을 통해 심도별 휨응력을 산정하였다. 분석 결과, 단일 현장타설말뚝의 변단면 부근에서 휨응력이 집중되어 재료파괴가 발생하기 가장 쉬운 것을 알 수 있었다. 이를 토대로, 단일 현장타설말뚝의 기둥-말뚝 직경비와 수평 균열하중비 관계를 통해 최적의 기둥-말뚝 직경비를 제안하였다. 연구 결과, 최적의 기둥-말뚝 직경비는 기둥-말뚝 직경비와 수평 균열하중비 관계 곡선의 변곡점 부근에서 산정되었으며, 단일 현장타설말뚝 설계에 최적 변단면 특성을 고려한다면 개선된 설계가 이루어질 수 있을 것으로 판단되었다.

Keywords

References

  1. AASHTO (2002). Standard specification for highway bridges, American Association of State Highway and Transportation Official.
  2. Ahn, S. Y. (2010). Proposed new design method of the pile bent structure considering plastic hinge, Ph. D. Thesis, Yonsei University (in Korean).
  3. Brinch Hansen, J. (1961). "The ultimate resistance of rigid piles against transversal forces." Bulletin No. 12, Danish Geotechnical Institute, Copenhagen, Denmark, pp. 5-9.
  4. Broms, B. (1964). "Lateral resistance of piles in cohesive soils." Journal of Geotechnical and Geoenvironment Engineering, ASCE, Vol. 90, No. 4, pp. 27-63.
  5. Brown, D. A. and Shie, C. F. (1991). "Some numerical experiments with a three-dimensional finite element model of laterally loaded piles." Computers and Geotechnics, Vol. 12, pp. 149-162. https://doi.org/10.1016/0266-352X(91)90004-Y
  6. California Department of Transportation Division of Engineering Services (2006). Caltrans seismic design criteria (Version 1.4).
  7. Chai, Y. H. (2002). "Flexural strength and ductility of extended pile-shafts. I: Analytical Model." Journal of Structural Engineering Vol. 128, No. 5, pp. 586-594. https://doi.org/10.1061/(ASCE)0733-9445(2002)128:5(586)
  8. FB-MultiPier (2012). User's manual: Ver. 4, Ensoft Inc.
  9. FHWA (1987). Drilled shaft, National Highway Institute.
  10. Jeong, S. S. and Seo, D. H. (2004). "Analysis of tieback walls using proposed p-y curves for coupled soil springs." Computers and Geotechnics, Vol. 31, pp. 443-456. https://doi.org/10.1016/j.compgeo.2004.05.003
  11. Jeong, S. S., Ahn, S. Y., Kwak D. O. and Lee, J. K. (2006). "A study on the lateral behavior of pile-bent structures with P-$\Delta$ effect." Journal of Korean Geotechnical Society, Korean Geotechnical Society, Vol. 22, No. 8, pp. 77-88 (in Korean).
  12. Jeong, S. S., Kwak D. O. and Ahn, S. Y. (2005). "Analysis of Pile-Bent(CIDH Shaft/Column) structure subjected to lateral loading." Korean Society of Civil Engineers conference, pp. 3968-3971 (in Korean).
  13. Jeong, S. S., Seo, D. H. and Kim, Y. H. (2009). "Numerical analysis of passive pile groups in offshore soft deposits." Computers and Geotechnics, Vol. 36, pp. 1164-1175. https://doi.org/10.1016/j.compgeo.2009.05.003
  14. Jeong, S. S., Sung, C. G., Ko, J. Y. and Kim, S. I. (2009). "Analysis of laterally loaded pile-bent structure with varying cross-sectional area." Journal of Korean Geotechnical Society, Korean Geotechnical Society, Vol. 25, No. 4, pp. 69-75 (in Korean).
  15. Jeremic, B. and Yang, Z. (2002). "Numerical analysis of pile behavior under lateral loads in layered elastic-plastic soils." International Journal for Numerical and Analytical Methods in Geomechanics, Vol. 26, pp. 1385-1406. https://doi.org/10.1002/nag.250
  16. John, W. (2001). Cyclic Large Deflection Testing of Shaft Bridges, Report No. 59A0183, University of California, Los Angeles.
  17. Kerop, D. J. (2001). Interaction between soil and full scale drilled shaft under cyclic lateral load, Ph. D. Thesis, University of California, Los Angeles.
  18. Kim, J. Y., Hwang, T. J. and Jeong, S. S. (2011). "Simplified analysis of pile bent structures and minimum reinforcement ratio." Journal of Korean Geotechnical Society, Korean Geotechnical Society, Vol. 27, No. 5, pp. 33-43 (in Korean).
  19. Kim, S. K., Yea, G. G., Kim, G. S. and Choi, Y. K. (2008). "A case study on horizontal displacement characteristics for single drilled shaft foundation." Korean Society of Civil Engineers conference, pp. 2017-2020 (in Korean).
  20. Kim, Y. H. and Jeong, S. S. (2011). "Analysis of soil resistance on laterally loaded piles based on 3D soil-pile interaction." Computers and Geotechnics, Vol. 38, No. 2, pp. 248-257. https://doi.org/10.1016/j.compgeo.2010.12.001
  21. Kim, Y. H., Jeong, S. S. and Won, J. O. (2009). "Effect of lateral rigidity of offshore piles using proposed p-y curves in marine clay." J. Marine Geosources and Geotechnology, Vol. 27, No. 1, pp. 53-77. https://doi.org/10.1080/10641190802625551
  22. Korea Expressway Corporation (2004). Design criteria for pile bent structure, Vol. 68, pp. 14-27 (in Korean).
  23. Matlock, H. (1970). "Correlation for design of laterally loaded piles in soft clay." The second annual offshore technology conference, Houston, TX, pp. 577-607.
  24. O'Neill, M. W. and Gazioglu. S, M. (1984). "Evaluation of p-y relationships in cohesive soils." Proceedings of a Analysis and Design of Pile Foundations, ASCE Geotechnical Engineering Division, 192-213.
  25. PLAXIS 3D Foundation (2008). PLAXIS 3D foundation user manual: Version 2.2, Brinkgreve, R.B. and Swolfs, W. M., PLAXIS Inc.
  26. Reese, L. C. and Wright, W. (1977). Drilled shaft manual, U. S. Department of Transportation.
  27. Son, H. S., Choi, I. K., Kang, D. O. and Yang, J. H. (2005). "Design of single column drilled pier foundation in incheon bridge viaduct." Korean Society of Civil Engineers Conference, pp. 959-962 (in Korean).
  28. Son, H. S., Choi, I. K., Lee, S. H. and Yang, J. H. (2006). "Seismic analysis and reinforcement details of integral pile shaft-column foundations." Journal of Earthquake Engineering Society of Korea, pp. 300-307 (in Korean).
  29. Sung, C. G. (2008). Analysis of lateral behavior of pile-bent structure subjected to change of pier's cross-sectional area, Master Thesis, Yonsei University (in Korean).
  30. Wallace, J. W., Fox, P. I. and Stewart, J. P. (2002). Cyclic large deflection testing of shaft bridges part II: Analytical Studies, Rep. No. 59A0183, California Dept. of Transportation. California.
  31. Won, J. O., Ahn, S. Y., Jeong, S. S., Lee, J. H. and Jang, S. Y. (2006). "Nonlinear three-dimensional analysis of pile group supported columns considering pile cap flexibility." Computers and Geotechnics, Vol. 33, pp. 355-370. https://doi.org/10.1016/j.compgeo.2006.07.007