OS-C501

Offshore Standard DNV-OS-C501, November 2013
Sec.4 Materials - laminates – Page 71
long test term curve. The characteristic long term test curve shall be based on the representative data's mean
curve minus two standard deviations. Details to obtain such a curve are given in [3.11]. (It shall be assumed that
the representative data are based on infinite measurements in [3.11.7], even if that was not the case in reality.)
8.10 Use of manufacturers data or data from the literature as representative data
8.10.1 There is a vast amount of data available, but unfortunately data are often not well documented and
essential information tends to be missing.
8.10.2 This section describes under which conditions such data may be used.
8.10.3 It shall be documented that the data come from a reputable source. This can be done in the following
way:
— all data were taken from calibrated test equipment
— data were witnessed by an independent third party or data were published and reviewed by at least two
independent research teams.
8.10.4 If these requirements are not met data can still be used as representative data, but all new materials data
have to be confirmed against these data, even if the requirements in [8.6] do not require a confirmation.
8.10.5 If information about processing and conditioning is missing, it shall always be assumed that the best
possible laminate has been tested under the most favourable conditions. The conservative assumptions in Table
4-14 should be made.
Table 4-14 Use of manufacturers data or data from the literature as representative data
Constituent materials:
Generic Fibre type
as stated
Type of weave
lay-up of UD-plies
Generic resin type (e.g. epoxy, polyester) as stated
Specific resin type (trade name)
high performance resin for the application
Process parameters:
Processing method
Autoclave
Processing temperature
high
Processing pressure
high
Process atmosphere (e.g. vacuum) vacuum
Post curing (temperature and time) yes
Control of fibre orientation
to less than 1 o
Fibre volume fraction
60% volume
Void content less than 1%
Conditioning parameters:
Temperature
room temperature
Water content of the laminate (wet, dry) Dry
Chemical environment
None
Loading rate
High
Measure values
mean values
Guaranteed minimum value
mean - 2 standard deviations (must be confirmed)
Standard deviation 15%
number of specimens 3
8.11 Confirming material data by component testing
8.11.1 Instead of confirming all material parameters individually component testing may be used to qualify an
analysis, as described in [8.11].
8.11.2 The advantage of this approach is its simplicity. The disadvantage is that component test results are
based on a combination of many aspects and it is usually not possible to separate individual parameters out of
the component test result.
8.11.3 When testing the component instead of individual material properties the restrictions given in Sec.10
[5] will apply and the qualification may not be valid for other geometry or any changes to the component.
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