Seismic performance assessment of fixed offshore structures by endurance time method

ABSTRACT

The aim of this paper is to consider the ability of endurance time (ET) method to estimate the seismic response of fixed offshore platforms at various excitation levels. In this way, various sources of nonlinear behaviour and challenging issues in the ET approach are included in the three-dimensional model of a real jacket platform utilising the finite element method. In addition to common-designed, over-designed and under-designed cases of this platform have been investigated to examine the effects of the structural characteristics on the ET response. To consider the accuracy and reliability of this approach, results of the ET method are compared with results of nonlinear time history analysis (THA) and response spectrum analysis (RSA) methods at different excitation levels. It is shown that the ET method can predict the seismic performance of the offshore structures with both small computational efforts and reasonable accuracy.

KEYWORDS:

• Seismic performance assessment
• endurance time method
• fixed offshore platforms
• nonlinear analysis

Acknowledgments

The authors wish to express their thanks to Prof. Homayoon Estekanchi and Dr. Tabeshpour of the Sharif University of Technology for their valuable comments.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Mohammad Ali Dastan Diznab http://orcid.org/0000-0002-3528-9540

Mohammad Saeed Seif http://orcid.org/0000-0002-1681-4012

Additional information

Funding

The current study was supported by Iran National Science Foundation (INSF) [grant number 97013485].