한국지반공학회논문집 (Journal of the Korean Geotechnical Society)

  • 제33권6호
  • /
  • Pages.5-16
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  • 2017
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  • 1229-2427(pISSN)
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  • 2288-646X(eISSN)
한국지반공학회 (Korean Geotechnical Society)
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동적 원심모형실험을 이용한 풍화토 지반에 놓인 얕은기초 시스템의 지진 시 회전 거동 특성 평가

Evaluation of Rocking Behaviors During Earthquake for the Shallow Foundation System on the Weathered Soil Using Dynamic Centrifuge Test

  • 하정곤 (한국과학기술원 건설 및 환경공학과) ;
  • 조성배 (K-water 연구원 인프라안전연구소) ;
  • 박헌준 (한국과학기술원 건설 및 환경공학과) ;
  • 김동수 (한국과학기술원 건설 및 환경공학과)
  • 투고 : 2016.05.16
  • 심사 : 2017.06.14
  • 발행 : 2017.06.30
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초록

얕은기초의 회전거동은 지진 시 기초 위 상부 구조물의 지진 하중을 줄여주는 장점이 있어 새로운 기초 내진설계개념으로 대두되고 있다. 본 연구에서는 현장 채취한 시료를 다짐하여 조성된 풍화토 지반에서 얕은기초의 회전거동을 평가하기 위하여 동적 원심모형실험을 수행하였다. 원심모형실험 모형은 풍화토 지반, 얕은기초, 단자유도 구조물로 이루어져 있으며, 지진 시 지반, 기초, 구조물의 가속도 응답과 기초의 침하 등 얕은기초 시스템의 거동을 관찰하였다. 입력 지진 하중이 클 경우 상부 구조물의 지진하중은 풍화토 지반에 놓인 기초 들뜸에 의한 회전거동으로 인해 줄어들었으며, 기초의 침하도 최대 기초폭의 0.5%이하로 작게 발현되었다. 이를 통하여 향후 추가적인 연구 및 검증을 바탕으로 국내 풍화토 지반에서 회전 거동 개념을 이용한 기초 설계 가능성을 확인하였다.

Rocking behavior of shallow foundation during the earthquake can reduce the seismic load of the superstructure. The dynamic centrifuge tests were performed to investigate the availability of using rocking behavior for the weathered soil condition. The centrifuge test model was composed of the weathered soil, shallow foundation and single degree of freedom structure. And the accelerations of soil, foundation and structure, and the foundation settlement were measured during the earthquake. From the test result, the seismic load of the structure for the strong earthquake input was reduced by the rocking behavior with foundation uplift and the maximum foundation settlement was less than 0.5% of the foundation width. This shows the potential that the rocking foundation concept can be used in the economical seismic design of foundation for the weathered soil in the future with additional research and verification.

키워드

참고문헌

  1. Ko, K.W, Ha, J.G, Park, H.J., and Kim, D.S. (2016), "Evaluation of Rocking Mechanism for Embedded Shallow Foundation via Horizontal Slow Cyclic Tests", Journal of the Korean Geotechnical Society, Vol.32, No.8, pp.47-59. https://doi.org/10.7843/KGS.2016.32.8.47
  2. Korean building code (2009), Architectural Institute of Korea.
  3. Anastasopoulos, I., Kourkoulis, R., Gelagoti, F., and Papadopoulos, E. (2012), "Rocking Response of SDOF Systems on Shallow Improved Sand: An Experimental Study", Soil Dynamics and Earthquake Engineering, Vol.40, pp.15-33. https://doi.org/10.1016/j.soildyn.2012.04.006
  4. ASCE/SEI 41-13. (2014), Seismic Evaluation and Retrofit of Existing Buildings. American Society of Civil Engineers, Reston, VA.
  5. BSSC (Building Seismic Safety Council). (1997), NEHRP guidelines for the seismic rehabilitation of buildings, Washington, DC.
  6. Deng, L., Kutter, B. L., and Kunnath, S. K. (2012a), "Centrifuge Modeling of Bridge Systems Designed for Rocking Foundations.", Journal of Geotechnical and Geoenvironmental Engineering, Vol.138, No.3, pp.335-344. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000605
  7. Deng, L. and Kutter, B. L. (2012b), "Characterization of Rocking Shallow Foundations Using Centrifuge Model Tests", Earthquake Engineering & Structural Dynamics, Vol.41, No.5, pp.1043-1060. https://doi.org/10.1002/eqe.1181
  8. Deng, L., Kutter, B. L., and Kunnath, S. K. (2014), "Seismic Design of Rocking Shallow Foundations: Displacement-Based Methodology", Journal of Bridge Engineering, American Society of Civil Engineers, Vol.19, No.11, pp.4014043.
  9. FEMA 356. (2000), Prestandard and Commentary for the Seismic Rehabilitation of Buildings. Federal Emergency Management Agency, Washington, D.C.
  10. Gajan, S. and Kutter, B. L. (2008), "Capacity, Settlement, and Energy Dissipation of Shallow Footings Subjected to Rocking", Journal of Geotechnical and Geoenvironmental Engineering, Vol.134, No.8, pp.1129-1141. https://doi.org/10.1061/(ASCE)1090-0241(2008)134:8(1129)
  11. Gajan, S. and Kutter, B. L. (2009), "Effects of Moment-to-Shear Ratio on Combined Cyclic Load-Displacement Behavior of Shallow Foundations from Centrifuge Experiments", Journal of Geotechnical and Geoenvironmental Engineering, Vol.135, No.8, pp.1044-1055. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000034
  12. Ha, J. G. (2017), Evaluation of the seismic rocking behavior for embedded shallow foundation via dynamic centrifuge test, Ph. D. Thesis, KAIST.
  13. Hakhamaneshi, M., Kutter, B. L., Moore, M., and Champion, C. (2016), "Validation of ASCE 41-13 Modeling Parameters and Acceptance Criteria for Rocking Shallow Foundations.", Earthquake Engineering Research Institute, Vol.32, No.2, pp.1121-1140.
  14. Kim, D.K., Lee, S.H., Kim, D.S., Choo, Y.W., and Park, H.G. (2015), "Rocking Effect of a Mat Foundation on the Earthquake Response of Structures", Journal of Geotechnical and Geoenvironmental Engineering, American Society of Civil Engineers, Vol.141, No.1, pp.4014085. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001207
  15. Kim, D. S., Kim, N. R., Choo, Y. W., and Cho, G. C. (2013), "A Newly Developed State-of-the-art Geotechnical Centrifuge in Korea", KSCE Journal of Civil Engineering, Vol.17, No.1, pp.77-84. https://doi.org/10.1007/s12205-013-1350-5
  16. Kim, D. S., Lee, S. H., Choo, Y. W., and Perdriat, J. (2013), "Self-balanced Earthquake Simulator on Centrifuge and Dynamic Performance Verification", KSCE Journal of Civil Engineering, Vol.17, No.4, pp.651-661. https://doi.org/10.1007/s12205-013-1591-3
  17. Kokkali, P., Abdoun, T., and Anastasopoulos, I. (2015), "Centrifuge Modeling of Rocking Foundations on Improved Soil", Journal of Geotechnical and Geoenvironmental Engineering, Vol.141, No.10, pp.4015041. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001315
  18. Kutter, B. L., Moore, M., Hakhamaneshi, M., and Champion, C. (2016), "Rationale for Shallow Foundation Rocking Provisions in ASCE 41-13", Earthquake Spectra, Vol.32, No.2, pp.1097-1119. https://doi.org/10.1193/121914EQS215M
  19. Lee, S. H., Choo, Y. W., and Kim, D. S. (2013), "Performance of an Equivalent Shear Beam (ESB) Model Container for Dynamic Geotechnical Centrifuge Tests", Soil Dynamics and Earthquake Engineering, Vol.44, pp.102-114. https://doi.org/10.1016/j.soildyn.2012.09.008
  20. Paolucci, R., Figini, R., and Petrini, L. (2013), "Introducing Dynamic Nonlinear Soil-Foundation-Structure Interaction Effects in Displacement-Based Seismic Design", Earthquake Spectra, Earthquake Engineering Research Institute, Vol.29, No.2, pp.475-496. https://doi.org/10.1193/1.4000135
  21. Shirato, M., Kouno, T., Asai, R., Nakatani, S., Fukui, J., and Paoulucci, R. (2008), "Large-scale Experiments on Nonlinear behavior of Shallow Foundations Subjected to Strong Earthquakes", Soils and Foundations, Vol.48, No.5, pp.673-692. https://doi.org/10.3208/sandf.48.673