Structural Engineering and Mechanics

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Formulation for seismic response of a ship-block system

  • Received : 2005.01.28
  • Accepted : 2006.02.02
  • Published : 2006.06.20
⟨ Previous Next ⟩

Abstract

This paper presents a complete and consistent formulation to study the seismic response of a free-standing ship supported by an arrangement of n keel blocks which are all located in a dry dock. It is considered that the foundation of the system is subjected to both horizontal and vertical in plane excitation. The motion of the system is classified in eight different modes which are Rest (relative), Sliding of keel blocks, Rocking of keel blocks, Sliding of the ship, Sliding of both keel blocks and the ship, Sliding and rocking of keel blocks, Rocking of keel blocks with sliding of the ship, and finally Sliding and rocking of keel blocks accompanied with sliding of the ship. For each mode of motion the governing equations are derived, and transition conditions between different modes are also defined. This formulation is based on a number of fundamental assumptions which are 2D idealization for motion of the system, considering keel blocks as the rigid ones and the ship as a massive rigid block too, allowing the similar motion for all keel blocks, and supposing frictional nature for transmitted forces between contacted parts. Also, the rocking of the ship is not likely to take place, and the complete ship separation from keel blocks or separation of keel blocks from the base is considered as one of the failure mode in the system. The formulation presented in this paper can be used in its entirety or in part, and they are suitable for investigation of generalized response using suitable analytical, or conducting a time-history sensitivity analysis.

Keywords

References

  1. Allen, R.H., Oppenheim, I.J., Parker, A.R. and Bielak, J. (1986), ' On the dynamic response of rigid body assemblies ', Earthq. Eng. Struct. Dyn., 14, 861-876 https://doi.org/10.1002/eqe.4290140604
  2. Den Hartog, J.P. (1985), Mechanical Vibration, Dover Publication
  3. Garcia, D. Lopez and Soong, T.T. (2003), ' Sliding fragility of block-type non-structural components, Part I: Unrestrained components ', Earthq. Eng. Struct. Dyn., 32, 111-129 https://doi.org/10.1002/eqe.217
  4. Garcia, D. Lopez and Soong, T.T (2003), ' Sliding fragility of block-type non-structural components. Part II: Restrained components ', Earthq. Eng. Struct. Dyn., 32, 131-149 https://doi.org/10.1002/eqe.218
  5. Harry, W. Shenton III and Nicholas, P. Jones (1991), ' Base excitation of rigid bodies, I: Formulation ', J. Eng. Mech., 117(10), 2286-2305 https://doi.org/10.1061/(ASCE)0733-9399(1991)117:10(2286)
  6. Harry, W. Shenton III and Nicholas, P. Jones (1991),' Base excitation of rigid bodies, II: Periodic slide-rock response ', J .Eng. Mech., 117(10), 2306-2328
  7. Harry, W. Shenton III (1996), ' Criteria for initiation of slide, rock and slide-rock rigid-body modes ', J. Eng. Mech., 122(7), 690-693 https://doi.org/10.1061/(ASCE)0733-9399(1996)122:7(690)
  8. Housner, George, W. (1963), ' The behavior of inverted pendulum structures during earthquake ', Bulletin of the Seismological Society of America, 53(2), 403-417
  9. Ikushima, T. and Nakazawa, T (1979), ' A seismic analysis method for a block column gas-cooled reactor core ', Nuclear Engineering and Design, 55(3), 331-342 https://doi.org/10.1016/0029-5493(79)90112-2
  10. Lee, T.H. (1975), ' Nonlinear dynamic analysis of a stacked fuel column subjected to boundary motion ', Nuclear Engineering and Design, 32(3), 337-350 https://doi.org/10.1016/0029-5493(75)90104-1
  11. Makris, N. and Roussos, Y. (2000), ' Rocking response of rigid blocks and near-source ground motions ', Geotenique. 50(3), 243-262 https://doi.org/10.1680/geot.2000.50.3.243
  12. Osinski, Z. (1998), Damping of Vibrations. Aa Balkema
  13. Pompei, A., Scalia, A. and Sumbatyan, M.A. (1998), ' Dynamics of rigid block due to horizontal ground motion ', J. Eng. Mech., 124(7), 713-717 https://doi.org/10.1061/(ASCE)0733-9399(1998)124:7(713)
  14. Psycharis, N. (1999),' Dynamic behavior of rocking two-block assemblies ', Earthq. Eng. Struct. Dyn., 19, 555-575 https://doi.org/10.1002/eqe.4290190407
  15. Rabbat, B.G and Russell, H.G (1985), ' Friction coefficient of steel on concrete or grout ', J. Struct. Eng., 111(3), 505-515 https://doi.org/10.1061/(ASCE)0733-9445(1985)111:3(505)
  16. Scalia, Antonio and Sumbatyan, Mezhlum A. (1996), ' Slide rotation of rigid bodies subjected to a horizontal ground motion ', Earthq. Engng. Struct. Dyn., 25, 1139-1149 https://doi.org/10.1002/(SICI)1096-9845(199610)25:10<1139::AID-EQE606>3.0.CO;2-S
  17. Spanos, Pol D., Roussis, Panayiotis C. and Politis, P.A. (2001), ' Dynamic analysis of stacked rigid blocks ', Soil Dyn. Earthq. Eng., 21, 559-578 https://doi.org/10.1016/S0267-7261(01)00038-0
  18. Taniguchi, Tomoyo, Mentani, Yukio, Komori, Hiroharu and Yashihara, Takeo (1998), ' Governing equation of slip of flat bottom cylindrical shell tank without anchor and uplifting of bottom plate ', Seismic Engineering, PVP-364, 55-61
  19. Taniguchi, Tomoyo (2002),' Non-linear response analysis of rectangular rigid bodies subjected to horizontal and vertical ground motion ', Earthq. Engng. Struct. Dyn., 31(8), 1481-1500 https://doi.org/10.1002/eqe.170
  20. Yim, Chik-Sing, Chopra, Anil K. and Penzien, Joseph (1980), ' Rocking response of rigid blocks to earthquakes ', Earthq. Engng. Struct. Dyn., 31, 565-587
  21. Younis, Christos J. and Tadjbakhsh, Iradj G. (1984),' Response of sliding rigid structure to base excitation ', J. Eng. Mech., 110(3), 417-432 https://doi.org/10.1061/(ASCE)0733-9399(1984)110:3(417)
  22. Zhang, Jian and Makris, Nicos (2001), ' Rocking response of free-standing blocks under cyclonical pulses ', J .Eng. Mech., 127(5), 473-483 https://doi.org/10.1061/(ASCE)0733-9399(2001)127:5(473)
  23. Zhong, Jian and Makris, Nicos (2001), ' Rocking response of anchored blocks under pulse-type motion ', J. Eng. Mech., 127(5), 484-493 https://doi.org/10.1061/(ASCE)0733-9399(2001)127:5(484)

Cited by

  1. Sensitivity analysis for seismic response of a ship-block system vol.23, pp.3, 2006, https://doi.org/10.12989/sem.2006.23.3.309