The electronic pdf versions of the documents found through http://www.dnv.com/ are the officially binding versions. Copyright Det Norske Veritas.

[Book] [Expand] [Collapse] [Search Forms] [Previous Section with Hits] [Next Section with Hits] [Clear Search] [Help]

Expand Search

B: Assumptions and Applications [Table of Contents] D: References

DNV-OS-C102 Structural Design of Offshore Ships

[-] Sec.1: Topside stru
[-] C: Definition

Sec.1
C. Definition

Sec.1
C 100   Verbal forms

Sec.1 C
101   Shall: Indicates a mandatory requirement to be followed for fulfilment or compliance with the present standard. Deviations are not permitted unless formally and rigorously justified, and accepted by all relevant contracting parties.

Sec.1 C
102   Should: Indicates a recommendation that a certain course of action is preferred or particularly suitable. Alternative courses of action are allowable under the standard where agreed between contracting parties but shall be justified and documented.

Sec.1 C
103   May: Indicates a permission, or an option, which is permitted as part of conformance with the standard.

Sec.1
C 200   Terms

Sec.1 C
201   Standard terms are given in DNV-OS-C101.

Sec.1 C
202   Drilling vessel: A unit used for drilling in connection with exploration and/or exploitation of oil and gas. The unit is generally operating on the same location for a limited period of time and is normally equipped with dynamic positioning system with several thrusters. The unit follows the normal class survey program.

Sec.1 C
203   Well intervention vessel: A unit equipped for performing wire-line intervention (without riser) of subsea wells and or coiled tubing of subsea. The unit is generally operating on the same location for a limited period of time and is normally equipped with dynamic positioning system with several thrusters. The unit follows the normal class survey program.

Sec.1 C
204   Floating production and offloading unit: A unit used for the production of oil with arrangement for offloading to a shuttle tanker. The units normally consist of a hull, with turret or spread mooring arrangement, and production facilities above the main deck. The unit can be relocated, but is generally located on the same location for a prolonged period of time.

Sec.1 C
205   Floating storage and offloading unit: A unit used for storage of oil with arrangement for offloading to a shuttle tanker. The units normally consist of a hull, with turret or spread mooring system. The unit is equipped for crude oil storage. The unit can be relocated, but is generally located on the same location for a prolonged period of time.

Sec.1 C
206   Floating production, storage and offloading unit: A unit used for the production and storage of oil with arrangement for offloading to a shuttle tanker. The unit is equipped for crude oil storage. The unit is normally moored to the seabed with production facilities on the main deck. The unit can be relocated, but is normally located on the same location for a prolonged period of time.

Sec.1 C
207   Floating production, drilling, storage and offloading unit: A unit used for drilling, storage and production of oil with arrangement for offloading to a shuttle tanker. The unit is equipped for crude oil storage.

Sec.1 C
208   LNG/LPG Floating Production and Storage units: A unit with facilities for oil and gas production and storage. The unit is typically permanently moored. Due to the complexity of the unit more comprehensive safety assessment are typically carried out. The unit is normally equipped with solutions for quick disconnection of mooring lines between the shuttle tanker and the oil and gas producing and storage unit.

Sec.1 C
209   Turret: A device providing a connection point between the unit and the combined riser- and mooring- systems, allowing the unit to freely rotate (weather vane) without twisting the risers and mooring lines.

Sec.1 C
210   Temporary mooring: Anchoring in sheltered waters or harbours exposed to moderate environmental loads.

Sec.1 C
211   Structural design brief: A document providing criteria and procedures to be adopted in the initial stages of the design process. The structural design brief should include analytical methods, procedures and methodology used for the structural design taking all relevant limiting design criteria into account. Owner's additional specification, if any, should be clearly described in the structural design brief.

Sec.1 C
212   Service life: The expected life time of the unit

Sec.1 C
213   Fatigue life: Service life ´ Design Fatigue Factor (DFF)

Sec.1 C
214   Probability of exceedance:
10-4: Appr. daily return period
10-8: Appr. 20 years return period
10-8.7: Appr. 100 years return period


Sec.1 C
215   Annual probability:
10-1: 10 years return period
10-2: 100 years return period

Sec.1
C 300   Symbols

Sec.1 C
301   The following Latin characters are used in this standard:

Sec.1 C
Table C1 Latin characters used  
V  Speed in knots  
CW Wave coefficient as given in DNV Rules for Classification of Ships Pt.3 Ch.1 Sec.4  
av Vertical acceleration 
at Transverse acceleration 
al Longitudinal acceleration 
Mwv Vertical wave bending moment 
Mwh Horizontal wave bending moment 
Qwv Vertical wave shear force 



Sec.1 C
302   The following Greek characters are used in this standard:

Sec.1 C
Table C2 Greek characters used  
h0 Basic usage factor 
b Coefficient depending on type of structure 
hp Permissible usage factor 

Sec.1
C 400   Abbreviations

Sec.1 C
401   The abbreviations given in Table C3 are used in this standard. Definitions are otherwise given in DNV-OS-C101 'Design of Offshore Steel Structures, General' (LRFD method).

Sec.1 C
Table C3 Abbreviations  
Abbreviation In full 
DFF  Design fatigue factor  
NDT  Non-destructive testing  
SCF  Stress concentration factors  
WSD  Working stress design  

B: Assumptions and Applications [Table of Contents] D: References