General
1 For the purpose of applying composite materials for load-bearing "A" class of "B" class
divisions of superstructures, structural bulkheads except for those in contact with liquids,
decks and deckhouses of ships, as equivalent to steel, it should be demonstrated that they
are able to withstand the applied loads during and at the end of fire, by means of the
following test procedure.
2 The composite materials should meet criteria of non-combustibility, passage of
smoke/flame and toxicity as determined by relevant test procedures developed by the
Organization.*
Definitions
3 The following definitions apply for the purpose of these guidelines:
- "Composite material" means a material with an organic or inorganic matrix (e.g.
polyester, melamine formaldehyde, phenolic resins or ceramic), reinforced by fibres
(e.g. glass, carbon, ceramic fibres) with suitable orientation.
- "Composite strength" means the tension, compression, bending, shear and torsion
ultimate strength at each temperature multiplied by a safety factor assigned to the
satisfaction of the Administration (e.g. 0.8) (see figure 1).
- "Core region" means the inner part or the outer part not exposed to fire of the
load-bearing division, capable of a minimum residual strength and stiffness to
withstand the applied loads during and at the end of fire.
- "Insulation" means the outer part of the load-bearing division with suitable
thickness to ensure thermal protection of the core region (i.e. the structural
strength of the insulating material, if any, should be fully disregarded).
- "Load-bearing division" means a panel made of composite material(s) (e.g. layers
of laminates, adhesives bonds and a core region of composite or other materials)
which is able to withstand the applied functional, environmental and local loads.
- "Transition temperature" means the temperature corresponding to an abrupt loss of
stiffness of the material (see figure 2, when applicable).
Determination of structural properties
4 Tests should be performed on small specimens of suitable shape, including all the
elements of the core region. Such specimens should be tested in a uniform temperature
furnace and the temperature of the core region should be determined, to define the
behavioural relationship between the applied loads and temperature.
5 The tension, compression, bending, shear and torsion loads appropriate for the material's
application on board, should be scaled and applied in specimens with a different orientation
to take account of the anysotropic behaviour of the composite material.
6 Tests should be performed at a temperature of the furnace increasing from the ambient
temperature to the temperature foreseen for the core region at the end of the standard fire
test on the prototype of the division of composite material.
7 The composite strength should be scaled from the dimensions of the small specimens to
the actual dimensions of the composite material used on board.
Selection of the critical temperature
8 The critical temperature is the temperature of the composite strength corresponding to
the most critical applied load relative to the application on board. When the application
involves a combination of load (e.g. compression and bending), the most critical load
should be defined for the most unfavourable load combination.
9 The critical temperature should not exceed the transition temperature, when applicable, to
ensure that deformation is adequate for the intended application.
Performance of standard fire tests
10 Standard fire tests should be performed on larger scale specimens, in accordance with
the provisions of SOLAS regulation II-2/3.2 and the Recommendation on Fire Test
Procedure for "A", "B" and "F" Class Divisions, adopted by the Organization by resolution
A.754(18).
10 In addition to SOLAS regulations II-2/3.3 and II-2/3.4, the temperature in any point of
the most exposed side of the core region of load-bearing divisions should be lower than
the critical temperature. Special considerations should be given to the measured
temperatures, thermal distortions and transmission of loads of joints.
* Refer to:
.1 Improved recommendation on test method for qualifying marine construction
materials as non-combustible (resolution A.472(XII)).
.2 Recommendation on fire test procedures for "A", "B" and "F" class divisions
(resolution A.754(18)).
.3 Interim standards for measuring smoke and toxic product of combustion (resolution MSC.41(64)).