Journal of the Korean GEO-environmental Society (한국지반환경공학회 논문집)

Korean Geo-Environmental Society (한국지반환경공학회)
권호 표지

Numerical Modeling of Large Triaxial Compression Test with Rockfill Material Considering 3D Grain Size Distribution

3차원 입도분포를 고려한 락필재료의 대형삼축압축시험 수치모델링

  • 노태길 (서울시립대학교 토목공학과) ;
  • 전제성 (인덕대학교 건설정보공학과) ;
  • 이송 (서울시립대학교 토목공학과)
  • Published : 2012.10.01
⟨ Previous Next ⟩

Abstract

In this research, the algorithm for simulating specific grain size distribution(GSD) with large diameter granular material was developed using the distinct element analysis program $PFC^{3D}$(Particle Flow Code). This modeling approach can generate the initial distinct elements without clump logic or cluster logic and prevent distinct element from escaping through the confining walls during the process. Finally the proposed distinct element model is used to simulate large triaxial compression test of the rockfill material and we compared the simulation output with lab test results. Simulation results of Assembly showed very well agreement with the GSD of the test sample and numerical modeling of granular material would be possible for various stress conditions using this application through the calibration.

본 연구에서는 개별요소해석 프로그램인 $PFC^{3D}$를 이용하여 대입경 조립재료의 특정 입도분포를 구현하는 알고리즘을 개발하였다. 기존의 입자 형상이나 입도를 구현하기 위해 사용되었던 clump logic 또는 cluster logic을 사용하지 않으며 요소의 경계면 이탈 현상과 경계면 파괴 등을 방지할 수 있는 초기 개별요소 모델링 기법을 고안하였다. 최종적으로 대입경 조립재료에 대한 대형 삼축압축시험을 수치 모델링하고 실내시험 결과와 비교하였다. 해석 결과, 실제 시료의 입도분포와 매우 흡사한 분포의 개별요소를 생성할 수 있었고, 적정 미시물성치 산정 과정(calibration)을 통해 다양한 구속응력 조건에 대한 대입경 조립재료의 특정 입도분포하에서의 전체적인 수치 모델링이 가능하였다.

Keywords

References

  1. Cho, N. K, Yoo, C. S. and Lee, D. Y.(2008), Modeling Direct Shear Test of Crushed Stone Using DEM, Journal of Korean Geotechnical Society, Vol. 24, No. 1, pp. 15-23.
  2. Cundall, P. A.(2001), A Discontinuous Future for Numerical Modelling in Geomechanics, Proceedings of the Institution of Civil Engineers, London, UK., Geotechnical Engineering, Vol. 149, No. 1, pp. 41-48.
  3. Cundall, P. A. and Strack, O. D. L.(1979), A Discrete Numerical Model for Granular Assemblies, Geotechnique, Vol. 29, No. 1, pp. 47-65. https://doi.org/10.1680/geot.1979.29.1.47
  4. Deresiewicz, H.(1958), Mechanics of Granular Matter, Advances in Applied Mechanics, Vol. 5, H. L. Dryden, et al., Eds. New York : Academic Press, Inc., pp. 233-306.
  5. Hainübchner, E., Potthoff, S., Konietzky, H. and Kamp, L.(2002), Particle Based Modeling of Shear Box Tests and Stability Problems for Shallow Foundations in Sand, Numerical Modeling in Micromechanics via Particle Methods, A. A. Balkema, Lisse, pp. 151-156.
  6. Itasca Consulting Group, Inc.(2004), PFC3D User's Guide & Fish in PFC3D, Minneapolis, Minnesota.
  7. Jeon. J. S. and Kim. K. Y.(2008), Fluid Injection Simulation Considering Distinct Element Behavior and Fluid Flow into the Ground, Journal of Korean Geotechnical Society, Vol. 24, No. 2, pp. 67-75.
  8. Jeon. J. S, Kim. K. Y. and Shin. D. H.(2006), Modelling of Large Triaxial Test with Rockfill Materials by Distinct Element Method, Journal of Korean Geotechnical Society, Vol. 22, No. 10, pp. 111-120.
  9. Lee. W. H, Lim. H. D.(2007), Analysis of Fine Particle Transfer and Shear Strength Increase using PFC in Permeation Grouting, Journal of Korean Geotechnical Society, Vol. 23, No. 11, pp. 49-58.
  10. Li, L. and Holt, R. M.(2002), Development of Discrete Particle Modeling Towards Numerical Laboratory, Numerical Modeling in Micromechanics via Particle Methods, A. A. Balkema, Lisse, pp. 19∼27.
  11. Thomas, P. A. and Bray, J. D.(1999), Capturing Nonspherical Shape of Granular Media with Disk Clusters, Journal of Geotechnical and Geoenvironmental Engineering, Vol. 125, No. 3, pp. 169-178. https://doi.org/10.1061/(ASCE)1090-0241(1999)125:3(169)
  12. Ting, J. M. and Corkum, B. T.(1988), Strength Behavior of Granular Materials using Discrete Numerical Modelling, Numerical Method in Geomechanics, Innsbruck, pp. 305-310.
  13. Ting, J. M., Corkum, B. T., Kauffiman, C. R. and Greco, C.(1989), Discrete Numerical Model for Soil Mechanics, Journal of Geotechnical and Geoenvironmental Engineering, Vol. 115, No. 3, pp. 379-398. https://doi.org/10.1061/(ASCE)0733-9410(1989)115:3(379)