All Issue

2016 Vol.32, Issue 4
Numerical Simulation of Dynamic Soil-pile Interaction for Dry Condition Observed in Centrifuge Test

원심모형실험에서 관측된 건조 지반-말뚝 동적 상호작용의 수치 모델링

Sun-Yong Kown1
,
Seok-Jung Kim2
,
Min-Taek Yoo3*
권 선용1
,
김 석중2
,
유 민택3*
1Associate Researcher, Div. of Technology Development, Samsung C&T
2Assistant Manager, Technology R&D Institute, Soosung Engineering Co., Ltd.
3Senior Researcher, High-speed Railroad Systems Research Center, Korea Railroad Rssearch Institute
1삼성물산 건설부문 전임연구원
2수성엔지니어링 대리
3한국철도기술연구원 고속철도연구본부 선임연구원
*교신저자. *Corresponding Author. 
30 April 2016. pp. 5-14
PDF XML Citation
Abstract

Numerical simulation of dynamic soil-pile-structure interaction embedded in a dry sand was carried out. 3D model of the dynamic centrifuge model tests was formulated in a time domain to consider nonlinear behavior of soil using the finite difference method program, FLAC3D. As a modeling methodology, Mohr-Coulomb criteria was adopted as soil constitutive model. Soil nonlinearity was considered by adopting the hysteretic damping model, and an interface model which can simulate separation and slip between soil and pile was adopted. Simplified continuum modeling (Kim et al., 2012) was used as boundary condition to reduce analysis time. Calibration process for numerical modeling results and test results was performed through the parametric study. Verification process was then performed by comparing numerical modeling results with another test results. Based on the calibration and validation procedure, it is identified that proposed modeling method can properly simulate dynamic behavior of soil-pile system in dry condition.

Keywords
Numerical simulation
Centrifuge model test
Finite difference method
Dynamic soil-pile interaction

건조토 지반에 근입된 지반-말뚝 시스템의 동적 거동을 정확히 예측하기 위해 3차원 수치 모델링을 수행하였다. 제안된 모델은 강진 시 지반의 비선형 거동을 적절하게 모사하기 위해 상용 유한 차분 프로그램인 FLAC3D를 이용하여 시간 영역에서 해석이 수행되었다. 모델링 방법론으로써 지반 구성 모델은 Mohr-Coulomb 탄소성 모델을 적용하였으며 지반 전단 탄성 계수의 비선형적인 감소를 모사할 수 있는 이력 감쇠 모델을 적용하였다. 진동 시 지반-말뚝 간의 완전 접촉, 미끄러짐, 분리 현상을 모두 모사하는 경계요소 모델을 적용하였으며 경계요소 모델을 구성하는 스프링 계수는 탄성이론에 기초하여 결정되어, 내장 함수인 FISH를 통해 깊이에 따라 연속적으로 입력되었다. 경계 조건의 경우, 지반-말뚝 상호작용의 영향을 받는 근역 지반만 메쉬를 생성하고 근역 지반의 경계부에 원역 지반의 가속도-시간 이력을 입력하는 방식인 단순화 연속체 모델링 기법(Kim et al., 2012)을 적용함으로써 해석 효율을 증가시키고자 하였으며 적절한 최대지반탄성계수와 항복 깊이의 설정으로 지반의 비선형 거동을 더욱 정확히 모사하고자 하였다. 수치 해석의 오차를 최소화하고 모델의 신뢰성을 확보하기 위해, Yoo(2013)이 수행한 원심모형시험 결과와 수치 해석 결과와의 비교를 통해 제안된 기법의 캘리브레이션을 수행하였으며, 말뚝 최대 휨 모멘트와 말뚝 횡방향 최대 변위의 깊이 별 분포가 다양한 입력 하중 조건에서 실험 결과를 적절히 모사하고 있는 것을 확인하였다. 또한, 제안된 수치 모델의 적용성 평가를 위해 다른 실험 결과와의 비교 검증을 수행하였다.

References
1
1.Beringen, F. L., Windle, D., and Van Hooydonk, W. R. (1979), Results of loading tests on driven piles in sand, Fugro, Netherlands.
2
2.Boulanger, R.W. and Curras, C.J. (1999), “Seismic Soil-Pile-Structure Interaction Experiments and Analyses”, Journal of Geotechnical and Geoenvironmental Engineering, American Society of Civil Engineers, Vol.125, No.9, pp.750-759.
3
3.Chang, D.W., Lin, B.S., and Cheng, S.H. (2007), “Dynamic Pile behaviors Affecting by Liquefaction from EQWEAP Analysis”, In Proceedings: 4th International conference on earthquake geotechnical engineering, Thessaloniki, Greece; pp.1336.
4
4.Cheng, Z. h. and Jeremic, B. (2009), “Numerical Modeling and Simulation of Pile in Liquefiable Soil”, Soil Dynamics and Earthquake Engineering, 29, pp.1404-1416.
5
5.Comodromos, E. M., Papadopoulou, M. C., and Rentzepris, I. K. (2009), “Pile Foundation Analysis and Design Using Experimental Data and 3-D Numerical Analysis”, Computers and Geotechnics, 36, pp.819-836.
6
6.Hardin, B. O. and Drnevich, V. P. (1972). “Shear Modulus and Damping in Soils: Design Equations and Curves”, Journal of the Soil Mechanics and Foundations Division, ASCE, Vol.98, No.SM7, July 1972, pp.667-692.
7
7.Iai, S., Matsunaga, Y., and Kameoka, T. (1992), “Parameter Identification for a Cyclic Mobility Model”, Report of the Port and Harbour Research Institute. 29(4): pp.57-83.
8
8.Itasca Consulting Group (2006), FLAC3D (Fast Lagrangian Analysis of Continua in 3Dimensions) User’s Guide, Minnesota, USA.
9
9.Kim, S. H., Kwon, S. Y., Kim, M. M., and Han, J. T. (2012), “3D Numerical Simulation of a Soil-Pile System Under Dynamic Loading”, Marine Georesources & Geotechnology, 30(4), pp.347-361.
10
10.Kraft Jr, L. M. (1990), “Computing Axial Pile Capacity in Sands for Offshore Conditions”, Marine Georesources & Geotechnology, 9(1), pp.61-92.
11
11.Kwon, S. Y. (2014), “Numerical Simulation of Dynamic Soil-Pile- Structure Interactive Behavior Observed in Centrifuge Tests”, Ph. D. Thesis, Seoul National University, South Korea
12
12.Liyanapathirana, D. S. and Poulos, H. G. (2010), “Analysis of Pile behaviour in Liquefying Sloping Ground”, Computers and Geotechnics, 37(1), pp.115-124.
13
13.Martin, G. R. and Chen, C. Y. (2005), “Response of Piles due to Lateral Slope Movement”, Computers and Structures, Vol.83, pp.588-598.
14
14.Miwa, S., Ikeda, T., and Sato, T. (2006), “Damage Process of Pile Foundation in Liquefied Ground during Strong Ground Motion”, Soil Dynamics and Earthquake Engineering, 26(2), pp.325-336.
15
15.Randolph, M. F., Dolwin, R., and Beck, R. (1994), “Design of Driven Piles in Sand”, Geotechnique, 44(3), pp.427-448.
16
16.Reddy, E. S., Chapman, D. N., and Sastry, V. V. (2000), “Direct Shear Interface Test for Shaft Capacity of Piles in Sand”, Geotechnical Testing Journal, 23(2), pp.199-205.
17
17.Tahghighi, H. and Konagai, K. (2007), “Numerical Analysis of Nonlinear Soil-pile Group Interaction under Lateral Loads”, Soil Dynamics and Earthquake Engineering, 27(5), pp.463-474.
18
18.Uzuoka R., Sento N., and Kazama M. (2007), “Three-dimensional Numerical Simulation of Earthquake Damage to Group-piles in a Liquefied Ground”, Soil Dynamics and Earthquake Engineering, 27, pp.395-413.
19
19.Yang, E. K. (2009), “Evaluation of Dynamic p-y curves for a Pile in Sand from 1g Shaking Table Tests”, Ph. D. Thesis, Seoul National University, South Korea.
20
20.Yoo, M. T. (2013), “Evaluation of dynamic pile behavior by centrifuge tests considering kinematic load effect,” Ph. D. Thesis, Seoul National University, South Korea.
Information
  • Publisher :The Korean Geotechnical Society
  • Publisher(Ko) :한국지반공학회
  • Journal Title :Journal of the Korean Geotechnical Society
  • Journal Title(Ko) :한국지반공학회 논문집
  • Volume : 32
  • No :4
  • Pages :5-14
  • Received Date : 2016-01-19
  • Revised Date : 2016-05-07
  • Accepted Date : 2016-03-10
  • DOI :https://doi.org/10.7843/kgs.2016.32.4.5
Journal Informaiton Journal of the Korean Geotechnical Society Journal of the Korean Geotechnical Society
Archives
: Vol.23~28 (2007~2012)
  • NRF
  • KOFST
  • KISTI Current Status
  • KISTI Cited-by
  • crosscheck
  • orcid
  • open access
  • ccl
Journal Informaiton Journal Informaiton - close