Seismically-induced displacements of a suction caisson in soft clay

A.J. Brennan, S.P.G. Madabhushi, P. Cooper

    Research output: Chapter in Book/Report/Conference proceedingOther chapter contribution

    1 Citation (Scopus)

    Abstract

    The seismic design for offshore foundations is based predominantly on experience onshore. This paper describes the results of dynamic centrifuge tests performed to validate the performance of a suction caisson installed in normally consolidated clay. The main objective is to evaluate the likely plastic displacement under different shaking levels. Permanent displacement results indicate that the displacements experienced are well within the allowable movement for the foundation considered, even though a strength based design approach would consider this to be a failure. Larger earthquakes are seen to produce comparatively smaller displacements. It is concluded that the when designing for seismic loading, if some displacement is permissible then a performance-based approach allowing some displacement proves significantly less conservative than a purely strength-based design. It is also concluded that dynamic response analyses should consider the strength of soil, as this can act as a fuse against large amplitude shear waves.
    Original languageEnglish
    Title of host publicationFrontiers in Offshore Geotechnics II - Proceedings of the 2nd International Symposium on Frontiers in Offshore Geotechnics
    Pages711-716
    Number of pages6
    Publication statusPublished - 1 Jan 2011

    Fingerprint

    Caissons
    Clay
    Seismic design
    Shear waves
    Centrifuges
    Electric fuses
    Dynamic response
    Earthquakes
    Plastics
    Soils

    Cite this

    Brennan, A. J., Madabhushi, S. P. G., & Cooper, P. (2011). Seismically-induced displacements of a suction caisson in soft clay. In Frontiers in Offshore Geotechnics II - Proceedings of the 2nd International Symposium on Frontiers in Offshore Geotechnics (pp. 711-716)
    Brennan, A.J. ; Madabhushi, S.P.G. ; Cooper, P. / Seismically-induced displacements of a suction caisson in soft clay. Frontiers in Offshore Geotechnics II - Proceedings of the 2nd International Symposium on Frontiers in Offshore Geotechnics. 2011. pp. 711-716
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    Brennan, AJ, Madabhushi, SPG & Cooper, P 2011, Seismically-induced displacements of a suction caisson in soft clay. in Frontiers in Offshore Geotechnics II - Proceedings of the 2nd International Symposium on Frontiers in Offshore Geotechnics. pp. 711-716.

    Seismically-induced displacements of a suction caisson in soft clay. / Brennan, A.J.; Madabhushi, S.P.G.; Cooper, P.

    Frontiers in Offshore Geotechnics II - Proceedings of the 2nd International Symposium on Frontiers in Offshore Geotechnics. 2011. p. 711-716.

    Research output: Chapter in Book/Report/Conference proceedingOther chapter contribution

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    Brennan AJ, Madabhushi SPG, Cooper P. Seismically-induced displacements of a suction caisson in soft clay. In Frontiers in Offshore Geotechnics II - Proceedings of the 2nd International Symposium on Frontiers in Offshore Geotechnics. 2011. p. 711-716