Probabilistic Seismic Assessment and Fragility Curves for Fixed Pile-Founded Offshore Platforms

Document Type : Original Research Article


1 Ph.D. Candidate, University of Qom, Qm, Iran

2 Assistant Professor, University of Qom, Qom, Iran


Fixed pile-founded offshore platforms installed in the seismic-prone areas are exposed to the risk of earthquake-induced disastrous failure and costly operation interruption. Accordingly, the development of applied seismic evaluation methodologies for these infrastructures is a matter of utmost importance. In the context of performance-based earthquake engineering (PBEE), probabilistic seismic assessments of fixed pile-founded offshore platforms have been investigated, here. A three-dimensional (3D) finite element model of a recently installed platform located in the South Pars Oil and Gas field of the Persian Gulf has been made. Soil-pile-structure interaction, as well as dynamic site response effects, has been considered. Probabilistic seismic demand modeling (PSDM) has been employed to manifest the efficient and sufficient ground motion intensity measures (IMs) which can rigorously predict the structural engineering demand parameters (EDPs). Derived from probabilistic seismic demand analysis (PSDA), the superb results have been also evaluated by means of the predominantly used method of incremental dynamic analysis (IDA). On the other hand, the drawn findings contributed to representing the fragility curves of the fixed pile-founded offshore platforms. The demonstrated results are highly recommended to be considered in related research.


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