Iranian Classification Society Rules

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Section 1 General


101. Application


1. Reductions in the scantlings of FRP Ships intended for Smooth Water Service are to be in accord- ance with the Table 1.1.


2. Reductions in the scantlings other than those given in Table 1.1 are to be in accordance with the discretion of the Society.


Table 1.1 Reductions in Scantlings


Item

Ratio of reduction

Section modulus of athwartship hull section Thickness of shell laminates(including keel) Minimum thickness of deck laminates

Thickness of single bottom or double bottom members


10 %

Section modulus of frame Section modulus of beam Section modulus of deck girder


15 %


3. Notwithstanding the requirements in 1 and 2, the scantlings of beams of deck intended to carry cargo, inner bottom plating and inner bottom longitudinals intended to carry heavy cargo, structural members of deep tanks, etc. are not to be reduced exceeding the values specified in the require- ments of the relevant chapter.


4. Sill height of hatchway, access opening, etc. may be reduced to the values given in Table 1.2.


Table 1.2 Sill Height of Hatchway, Access Opening, etc.(mm)



Location

Sill Height


Small deck opening (area: 1.5 mĪ or below)


Companionway

Access opening in superstructure end bulkhead

Upon upper deck and superstructure deck within fwd 0.25 Ã


380


300


300

Upon superstructure deck abaft the forward 0.25 Ã


230


100


100


103.

Direct strength calculations


1. Where scantlings of structural members are determined based on the direct strength calculation,

ANNEX 3-1 Guidance for the Direct Strength Assessmentof Rules and Guidance for

the Classification of High Speed and Light Crafts should be followed. If the application of the

Guidance is considered inappropriate, analysis method, loads and allowable stress as deemed appro-

priate by the Society may be applied.


2. Based on the results according to the direct strength calculation, the buckling strength of the struc- tural members are to be examined by using the method and allowable stress given in ANNEX 3-2

Guidance for the Buckling Strength Calculationof Rules and Guidance for the


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Guidance relating to the Rules for the Classification of FRP Ships 2014 1

Ch 1 General Ch 1

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Classification of High Speed and Light Crafts.