Offshore Structure Platform Design - Offshore Structures: Design, Construction and Maintenance - page 116

FIGURE 3.21 Conductor guides.

The boundary conditions should be clearly defined and should reflect the
actual support conditions for the structure.
Any model should generally consist of all primary framing members. Second-
ary members need not be explicitly modeled unless they facilitate the input of
loads or contribute to the structural action of a primary member.
Primary and secondary steelwork are classified as follows:

Topside primary steel includes all truss members, girders and horizontal
bracing.

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Jacket primary steel includes legs, diagonal bracing, horizontal bracing and
piles.

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Topside major secondary steel includes deck plate, grating, deck beams,
walkways, stairs and the crane pedestal.

●

Jacket major secondary steel includes cathodic protection, boat landing,
barge bumpers, walkways, appurtenance supports and mud mats.

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Local Member Axes
When constructing the model and running the software, the engineer should
review and appreciate the program s default member axis system and adopt

this system where possible. In addition, the default local member axis system
should be taken into consideration with vertical members (especially I-beams
and channels), because it will affect the orientation of the flanges.
The orientation of the members should follow a consistent format, as shown
in Figure 3.22 . That is, all like members should be oriented in the same
direction.
Member-end releases should be clearly defined and should reflect the actual
connection constraints for the member.
In most cases, the member-end offsets may be used where there are large
joint thicknesses. The offset should extend only to the face of the joint.

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