Section 5 Structural details
Clasification Society 2024 - Version 9.40
Clasifications Register Rules and Regulations - Rules and Regulations for the Classification of Offshore Units, July 2022 - Part 4 Steel Unit Structures - Chapter 8 Welding and Structural Details - Section 5 Structural details

Section 5 Structural details

5.1 General

5.1.1 For ship units, the design of structural details is to comply with Pt 10 Ship Units. For other unit types, the design of structural details is to comply with Pt 3, Ch 10, 5 Structural details of the Rules for Ships.

5.1.2 Additional requirements with respect to unit types as indicated in this Section should also be complied with, as applicable.

5.2 Arrangements at intersections of continuous secondary and primary members

5.2.1 In the lower hulls of column-stabilised units, where primary member webs are slotted for the passage of secondary members, web stiffeners are generally to be fitted normal to the face plate of the member to provide adequate support for the loads transmitted. The ends of web stiffeners are to be attached to the secondary members.

5.2.2 Web stiffeners may be flat bars of thickness, , with a minimum depth of 0,08or 75 mm, whichever is the greater. Alternative sections of equivalent moment of inertia may be adopted. The direct stress in the web stiffeners is to be determined in accordance with the Rules for Ships.

5.2.3 For units other than ship units and other surface type units, direct stress in the vertical web stiffener and the shear stresses in the lug, collar plate and weld connections are to be in accordance with Table 5.2.1 Factors of safety for the combined load cases – load case (a) in Pt 4, Ch 5, 2.1 General

5.2.4 For units other than ship units and other surface type units, the head used to calculate load transmitted to connections of secondary members is to be obtained from the following, as applicable:
  1. from Table 6.3.1 Watertight shell boundaries for lower hulls and columns of column-stabilised units and tension-leg units in Pt 4, Ch 6 Local Strength.
  2. from Table 6.3.4 Shell framing self-elevating units in Pt 4, Ch 6 Local Strength.
  3. from Table 6.7.1 Watertight and deep tank bulkhead scantlings in Pt 4, Ch 6 Local Strength.

5.3 Openings

5.3.1 Penetrations in main bracing members are to be avoided as far as possible. Details of essential penetrations or openings in main bracing members are to be submitted for consideration.

5.4 Other fittings and attachments

5.4.1 Gutterway bars at the upper deck are to be so arranged that the effect of main hull stresses on them is minimised and the material grade and quality of the bar are to be to the same standard as the deck plate to which it is attached.

5.4.2 Where attachments are made to rounded gunwale plates, special consideration will be given to the required grade of steel, taking into account the intended structural arrangement and attachment details. In general, the material grade and the quality of the attachment are to be to the same standard as the gunwale plates.

5.4.3 Fittings and attachments to main bracing members are to be avoided as far as possible. Where they are necessary, full details are to be submitted for consideration.


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