Designing Offshore Pipelines Facing the Geohazard of Active Seismic Faults

The current study focuses on the seismic design of offshore pipelines against active faults. After an extensive literature review of the provisions of the seismic norms worldwide and of the available analytical methods, the study simulates numerically (through finite-element modeling and strain-based criteria) the distress of offshore pipelines subjected to PGDs induced by active normal and reverse seismic faults at the seabed. Factors, such as the geometrical properties of the fault, the mechanical properties of the ruptured soil formations, and the pipeline characteristics, are examined. After some interesting conclusions regarding the seismic vulnerability of offshore pipelines, potential cost-effective mitigation measures are proposed taking into account constructability issues.

Authors:

• Maria S. Trimintziou
• Michael G. Sakellariou
• Prodromos N. Psarropoulos

Keywords:

• Active faults
• Seismic design
• offshore pipelines.

References:

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