DOI QR코드

DOI QR Code

액상화 해석을 위한 UBC3D-PLM의 적용성에 관한 연구

A Study on the Application of UBC3D-PLM for Soil Liquefaction Analysis

  • 투고 : 2021.12.17
  • 심사 : 2022.03.08
  • 발행 : 2022.03.31

초록

본 연구에서는 액상화 평가를 위해 적용 가능한 UBC3D-PLM을 활용하고자 상대밀도를 이용한 모델 변수 평가방법을 제안하였다. 또한, 가속도와 간극수압이 측정되고 있는 액상화 발생 지역의 사례에 대한 동적 유효응력해석 즉, 액상화 해석을 수행하여 실측 및 기존 Finn 해석결과와 비교 분석하였다. 본 연구를 통해 제안한 방법은 관련 모델에서 요구하는 필요 변수를 쉽게 평가할 수 있고, 액상화가 발생된 지역에서의 간극수압 거동을 예측할 수 있는 것으로 나타났다. 또한, 연구대상 지역의 경우 실측과 해석 모두 지진 가속도가 최대값에 도달한 후, 일정 시간이 경과한 시점에서 액상화가 발생하는 것으로 나타났다. 본 연구에서 적용한 UBC3D-PLM의 경우 실측과 유사한 과잉간극수압 거동을 예측하였고, 실측과 동일하게 액상화 발생여부를 평가하였다. 특히, 모래층에서의 과잉간극수압이 더 크게 발생하였지만, 실제는 실트층에서 액상화가 발생한 현상을 정확하게 구현하였다. 제안 모델 변수 평가방법과 UBC3D-PLM을 적용한 유한요소해석이 실제와 유사하게 액상화 발생 영역을 평가함으로써 향후 내진 설계 및 보강 시 액상화 보강 영역 선정에 활용될 수 있을 것으로 기대된다.

In this study, a model parameter evaluation method using relative density was proposed to utilize applicable UBC3D-PLM for liquefaction behavior. In addition, dynamic effective stress analysis, that is, liquefaction analysis, was performed on the case of the liquefaction occurrence region where acceleration and pore water pressure were measured, and compared with the actual measurement and the existing Finn analysis results. Through this study, it was found that the proposed method can easily evaluate the necessary parameters required by the related model and predict the pore water pressure behavior in the region where liquefaction occurs. In addition, in the case of the study area, both measurements and numerical analysis showed that liquefaction occurred when a certain amount of time elapsed after the earthquake acceleration reached the maximum value. In the case of UBC3D-PLM applied in this study, the excess pore water pressure behavior similar to the actual measurement was predicted, and the occurrence of liquefaction was evaluated in the same way as the actual measurement. In particular, although the excess pore water pressure in the sand layer was greater, the phenomenon in which liquefaction occurred in the silt layer was accurately realized. It is expected that the proposed model parameter evaluation method and finite element analysis applying UBC3D-PLM can be used to select the liquefaction reinforcement region in the future seismic design and reinforcement by evaluating the liquefaction occurrence region similarly to the real one.

키워드

참고문헌

  1. Beaty, M. H. and Byrne, P. M. (1998), An Effective Stress Model for Predicting Liquefaction Behaviour Of Sand, Geotechnical Earthquake Engineering and Soil Dynamics III ASCE Geotechnical Special Publication, Vol.1, No.75, pp.766-777.
  2. Beaty, M. H. and Byrne, P. M. (2011), UBCSAND Constitutive Model Version 904aR, Itasca UDM Web Site.
  3. Boulanger, R. W. and Ziotopoulou, K. (2015), PM4Sand (Version 3): A Sand Plasticity Model for Earthquake Engineering Applications, Center for Geotechnical Modeling Report No. UCD/CGM-15/01, Department of Civil and Environmental Engineering, University of California, Davis, Calif.
  4. BS 8002 (2015), Code of Practice For Retaining Structures.
  5. Byrne, P. M. (1991), A Cyclic Shear-Volume Coupling and Pore Pressure Model for Sand, International Conferences on Recent Advances in Geotechnical Engineering and Soil Dynamics.
  6. Daftari, A. (2015), New Approach in Prediction of Soil Liquefaction, Geo-Engineering and Mining of the Technische Universitat Bergakademie Freiberg Ph.D Thesis.
  7. Finn, W. L., Ledbetter, R. H. and Wu, G. (1994), Liquefaction in Silty Soils: Design and Analysis, Ground Failure under Seismic Conditions, Geotechnical Special Publication, No.44, pp.51-76.
  8. Hur, S. H., Lee, S. C., Kim, T. H. and Kim, B. J. (2021), Effect of Fines Content Including Clay on Liquefaction of Silt, Journal of The Korean Geotechnical Society, Vol.37, No.8, pp.5-13. https://doi.org/10.7843/KGS.2021.37.8.5
  9. Iai, S., Matsunaga, Y. and Kameoka, T. (1990), Strain Space Plasticity Model for Cyclic Mobility, Report of the Port and harbour Research Institute, Vol.29, No.4.
  10. Makra, A. (2013), Evaluation of The UBC3D-PLM Constitutive Model for Prediction of Earthquake Induced Liquefaction on Embankment Dams, TU Delft Msc Graduation Thesis.
  11. Meyerhof, G. G. (1957), Discussion on Research on determining the density of sands by penetration testing. Proc. 4th Int. Conf. on Soil Mech. and Found. Engrg., Vol. 1, No. 110.
  12. Negussey, D., Wijewickreme, W. K. D., and Vaid, Y. P. (1988), Constant-Volume Friction Angle of Granular Materials, Can. Geotech. J., Vol.25, No.1, pp.50-55 https://doi.org/10.1139/t88-006
  13. Park, S. S., Kim, Y. S., Byrne, P. M., Kim, D. M. (2005), A Simple Constitutive Model for Soil Liquefaction Analysis, Journal of The Korean Geotechnical Society Vol.21, No.8, pp. 27-35.
  14. PLAXIS (2012), Plaxis Liquefaction Model UBC3D-PLM.
  15. Prakash, S. (1981), Soil Dynamics, McGraw-Hil.
  16. Puebla, H., Byrne, M. and Phillips, M. (1997). Analysis of Canlex Liquefaction Embankments Prototype and Centrifuge Models. Canadian Geotechnical Journal, Vol.34, pp.641-657 https://doi.org/10.1139/t97-034
  17. Souliotis, C. and Gerolymos, N. (2016), Seismic Effective Stress Analysis of Quay Wall in Liquefiable Soil: The Case History of Kobe, Int. J. of GEOMATE, Vol.10, No.2, pp.1770-1775
  18. Tung, D. V., Tran, N. X., Yoo, B. S. and Kim, S. R. (2020), Evaluation of Input Parameters in Constitutive Models Based on Liquefaction Resistance Curve and Laboratory Tests, Journal of The Korean Geotechnical Society, Vol.36, No.6, pp. 35-46. https://doi.org/10.7843/KGS.2020.36.6.35
  19. VDC (Strong-Motion Virrual Data Center) (2021), Data of Superstition Hills, California 1987, https://www.strongmotioncenter.org/vdc/.
  20. Wu, J., Kammerer, A. M., Riemer, M. F., Seed, R. B. and Pestana, J. M. (2004), Laboratory Study of Liquefaction Triggering Criteria, 13th World Conf on Earthquake Eng, Vancouver BC, Canada: Paper No. 2580. c2004.