VESSEL IMPACT ANALYSIS FOR RISER PROTECTION FRAME AND PROTECTION NET SUPPORTS ON SEMI-SUBMERSIBLE OFFSHORE STRUCTURES

Yıl 2015, Sayı: 03, 3 - 22, 01.10.2015

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VESSEL IMPACT ANALYSIS FOR RISER PROTECTION FRAME AND PROTECTION NET SUPPORTS ON SEMI- SUBMERSIBLE OFFSHORE STRUCTURES

Öz

The objective of this paper is to assess the collision strength of the riser protection frame RPF and protection net PN supports of CPF Central Processing Facility of Semi-Submersible types. The PRF and PN supports are assessed for their collision strength when they are being collided by a supply vessel. The vessel colliding from north-side is assumed to be 18,000 tons and the one colliding from east/west side is assumed to be7000 tons. The focus of this paper is placed on general methodology and design of accident scenarios for CPF using more sophisticated tools such as the non-linear FEM which predicts the structural responses during and after a collision more precisely. There are two different designs for the RPF and PN supports and thus there are four structures i.e. RPF-01, RPF-02, PN-01 and PN-02. The expected kinetic energy for the collision from the north side is 20MJ. The collision energy from east/west side is 14MJ for side collision and 11MJ for bow/stern collision. With collision energy and plastic strain criteria, the collision capacities of the/-RPF and PN supports are estimated along the span of the structures for the given collision energies

Anahtar Kelimeler

Collision, Accident scenarios, Non-linear FEM, Riser Protection Frame RPF, Protection

Kaynakça

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