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3차원 시간이력해석을 통한 매설가스배관 종방향 지진응답 예측을 위한 경험적 설계법의 적용성 평가

Estimation of Applicability of Empirical Design Procedure for Predicting Seismic Response of Buried Gas Pipelines through 3D Time-history Analysis

  • 투고 : 2015.07.22
  • 심사 : 2015.09.13
  • 발행 : 2015.09.30

초록

매설가스배관의 내진설계에서 종방향 변형률은 중요한 평가 요소이다. 일반적으로 지진파를 조화파로 단순화하며 이의 파장은 토층의 주기와 전단파 속도의 곱으로 계산하여 매설관의 응답을 계산하는 경험적 설계방법이 널리 사용되지만 이의 정확성이 평가된 사례가 없다. 본 연구에서는 1차원 지반응답해석을 수행하여 매설심도에서의 변위-시간 이력을 추출하였으며, 이를 적용한 시간이력해석을 수행하여 매설관의 응답을 평가하였다. 매설관과 지반의 상호작용은 3차원 쉘-스프링 모델을 사용하여 모사하였다. 시간이력해석으로 계산된 결과는 설계방법과 비교하여 이의 정확성을 평가하였다. 비교 결과, 파장을 예측하기 위해서는 지반응답해석을 수행해야 하는 것으로 나타났다. 토층의 고유주기는 가속도의 탁월주기를 예측하는 데에는 활용될 수 있으나 변위의 탁월주기를 예측할 수 없는 것으로 나타났다. 반면, 파장에 대한 정확한 정보가 제공될 경우, 조화파에 대하여 제시된 해석해는 정확도가 높으며 설계에 적용 가능한 것으로 나타났다. 본 연구 대상이 동시베리아 지역에 적용될 매설가스관이라 동시베리아 지역의 대표 주상도를 해석 에 사용하였지만 본 연구의 결론은 기타 모든 지역에 적용 가능하며 가스관뿐만 아니라 상수도관 등 다양한 매설관에 적용 가능하다.

Longitudinal strain is an important component of seismic design for buried pipelines. A design procedure which determines the wavelength from site natural period and shear wave velocity of the soil layer and closed-form solutions of pipelines under a harmonic motion is typically used in design. However, the applicability of the procedure has not yet been thoroughly investigated. In this paper, displacement-time histories extracted from 1D site response analyses are used in 3D shell-spring model to accurately predict the response of pipelines. The results are closely compared to those from the design procedure. The area of interest is East Siberia. Performing a site response analysis to determine site specific displacement time history is highlighted. The site natural period may be used to predict the predominant period of the acceleration time history, but cannot be used to estimate the predominant period of the displacement time history. If an accurate estimate of the predominant period of the displacement time history is provided, it is demonstrated that the design equation can be successfully used to predict the response of pipelines.

키워드

참고문헌

  1. ALA (2001a), Guidelines for the design of buried steel pipe.
  2. ALA (2001b), "Seismic Fragility Formulations for Water Systems", sponsored by the American Lifelines Alliance, G&E Engineering Systems Inc., web site.
  3. ALA (2005), Seismic Guidelines for Water Pipelines.
  4. Anastasopoulos, I., Gerolymos, N., Drosos, V., Kourkoulis, R., Georgarakos, T., and Gazetas, G. (2007), "Nonlinear Response of Deep Immersed Tunnel to Strong Seismic Shaking", Journal of Geotechnical and Geoenvironmental Engineering, Vol.133, No.9, pp.1067-1090. https://doi.org/10.1061/(ASCE)1090-0241(2007)133:9(1067)
  5. API (2000), "Specification for Line Pipe", API specification 5L, Vol.42.
  6. Boulanger, R.W., Arulnathan, R., Jr, L., F. H., Torres, R.A., and Driller, M.W. (1998), "Dynamic Properties of Sherman Island Peat", Journal of Geotechnical and Geoenvironmental Engineering, Vol. 124, No.1, pp.12-20. https://doi.org/10.1061/(ASCE)1090-0241(1998)124:1(12)
  7. Cha, K.H., Lee, J.H., Jeong, M.C., and Kong, J.S. (2014), "Seismic Fragility Analysis of Buried Pipeline Considering Soil Dharacteristic", The 40th Korean Society of Civil Engineers, pp.477-478.
  8. Elnashai, A.S., Papanikolaou, V.K., and Lee, D.H. (2011), "Zeus NL-A System for Inelastic Analysis of Structures".
  9. Eurocode8 (2002), "Design of Structures for Earthquake Resistance", European Committee for Standardization (CEN), Eurocode 8, Brussels.
  10. Hashash, Y., Hook, J.J., and Schmidt, B. (2001), "Seismic Design and Analysis of Underground Structures", Tunnelling and Underground Space Technology, Vol.16, No.4, pp.247-293. https://doi.org/10.1016/S0886-7798(01)00051-7
  11. Hashash, Y.M.A., Groholski, D.R., Phillips, C.A., Park, D., and Musgrove, M. (2011), "DEEPSOIL 5.0, user Manual and Tutorial", University of Illinois, Urbana, IL, USA.
  12. Honegger, D.G., Nyman, D.J., Johnson, E.R., Cluff, L.S., and Sorensen, S.P. (2004), "Trans-Alaska Pipeline System Performance in the 2002 Denali Fault, Alaska, Earthquake", Earthquake spectra, Vol.20, No.3, pp.707-738. https://doi.org/10.1193/1.1779239
  13. KBC (2009), "Architectural Institute of Korea", KBC-2009, Architectural Institute of Korea.
  14. Kwak, H.J., Park, D.H., Lee, J.G., and Kang, J.M. (2015), "Effect of Incident Direction of Earthquake Motion on Seismic Response of Buried Pipeline", Journal of the Korean Geo-environmental Society, Vol.16, No.9, pp.43-51.
  15. Lee, D.H., Kim, B.H., Lee, H., and Kong, J.S. (2009), "Seismic behavior of a Buried Gas Pipeline under Earthquake Excitations", Engineering Structures, Vol.31, No.5, pp.1011-1023. https://doi.org/10.1016/j.engstruct.2008.12.012
  16. Park, D., Kwak, H.J., Kang, J.M., and Lee, Y.G. (2014), "Seismic Amplification Characteristics of Eastern Siberia", Journal of The Korean Geotechnical Society, Vol.30, No.10, pp.67-80. https://doi.org/10.7843/KGS.2014.30.10.67
  17. Qi, J., Ma, W., Sun, C., and Wang, L. (2006), "Ground Motion Analysis in Seasonally Frozen Regions", Cold regions science and technology, Vol.44, No.2, pp.111-120. https://doi.org/10.1016/j.coldregions.2005.09.003
  18. Sazonova, T.S., Romanovsky, V.E., Walsh, J.E., and Sergueev, D.O. (2004), "Permafrost Dynamics in the 20th and 21st Centuries Along the East Siberian Transect", Journal of Geophysical Research: Atmospheres (1984-2012), Vol.109, No.D1.
  19. St. John, C.M. and Zahrah, T.F. (1987), "Aseismic Design of Underground Structures", Tunnelling and Underground Space Technology, Vol.2, No.2, pp.165-197. https://doi.org/10.1016/0886-7798(87)90011-3
  20. Tromans, I.J. (2004), Behaviour of buried water supply pipelines in earthquake zones, Imperial College London (University of London), pp.1-348.
  21. Wu, Y., Sheng, Y., Wang, Y., Jin, H., and Chen, W. (2010), "Stresses and Deformations in a Buried oil Pipeline Subject to Differential Frost Heave in Permafrost Regions", Cold regions science and technology, Vol.64, No.3, pp.256-261. https://doi.org/10.1016/j.coldregions.2010.07.004