Page 120 - Numerical Analysis and Modelling in Geomechanics

WAVE-SEABED-STRUCTURE INTERACTION 101
influence on the pore pressure beneath the caisson (i.e. section 4), especially in
fine sand.

Conclusions
In this chapter, a general finite element model for the wave-seabed-structure
interaction (GFEM-WSSI) is presented. The proposed model overcomes the
major difficulty, i.e. encountered in the WSSI problem the determination of the
lateral boundary conditions. To demonstrate the application of the GFEM-WSSI
model, two practical examples with a pipeline and a caisson-type breakwater
have been used. The GFEM-WSSI model can also be extended further to other
structures such as offshore piles, piers and so on, as well as three-dimensional
cases in the future.

Acknowledgements
The author thanks Mr Cha and Mr Postma for their help with the generation of
graphs and routine computing work. The initial idea for the GFEM-WSSI model
was formed while the author worked at the Special Research Centre for Offshore
Foundation Systems (at the University of Western Australia), which was
supported by the Australian Research Council (ARC) Special Research Centre
Program. Financial support from the Australia-Taiwan exchange program (1999),
two ARC Small Grants (Griffith University) during 2000–2001 and the ARC
Large Grant (2001–2003) under Project no. A00104092 is also appreciated.

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