3D modeling and calculation of the fixed platform PFS-U (PESCARUS)

Abstract

Fixed platforms for the exploitation of petroleum deposits in the continental Black Sea Romanian platform are usually built like 3D welded truss structures (called “jacketâ€), using circular hollow sections. The structure has lateral inclined faces and it is grounded using steel driven piles disposed at the interior part of the jacket columns. This construction solution asks that the drilling can be done through the jacket slots only after the placement of the offshore into position.
For the “PESCARUS†location a fixed 4-faces platform was designed, in a new solution, having an open jacket at one of the faces (this was called “Fixed support platform PESCARUSâ€). This structure should allow the earlier drilling of the offshore wells (using a self-lifting platform) and in this case the construction of the PFS-U platform can be done at a later time.
For the design and calculation of this platform a full finite element 3D model was built. The model takes into account the real dimensions of element cross sections, the stiffness of the structure and the structure-soil interaction respectively. For the evaluation of the dynamic response of the structure a 3D dynamic finite element model was considered, the position of masses on the structure being very close to the real one.
This paper present important aspects regarding the finite element model, the evaluation of the location specific actions and loading hypotheses, but also the resistance and stability checks according to the accepted norms.