OS-C501

Offshore Standard DNV-OS-C501, November 2013
Contents – Page 7
5.7 Combination of environmental effects........................................................................................... 61
5.8 Blisters/osmosis ............................................................................................................................. 61
6 Influence of process parameters ............................................................................................................ 61
6.1 Introduction.................................................................................................................................... 61
6.2 Change of production method........................................................................................................ 62
6.3 Change of processing temperature and pressure............................................................................ 62
6.4 Change of post cure procedure ...................................................................................................... 62
6.5 Change of void content .................................................................................................................. 62
6.6 Correction for change in fibre volume fraction ............................................................................. 62
6.7 Control of fibre orientation:........................................................................................................... 63
6.8 Control of fibre tension:................................................................................................................. 63
7 Properties under fire............................................................................................................................... 64
7.1 Introduction.................................................................................................................................... 64
7.2 Fire reaction ................................................................................................................................... 64
7.3 Fire resistance ................................................................................................................................ 64
7.4 Insulation........................................................................................................................................ 64
7.5 Properties after the fire................................................................................................................... 64
8 Qualification of material properties ...................................................................................................... 65
8.1 Introduction.................................................................................................................................... 65
8.2 General test requirements .............................................................................................................. 65
8.3 Selection of material qualification method.................................................................................... 65
8.4 Direct measurement ....................................................................................................................... 65
8.5 Representative data ........................................................................................................................ 66
8.6 Qualification against representative data....................................................................................... 66
8.7 Confirmation testing for static data................................................................................................ 69
8.8 Confirmation testing for long term data - high safety class........................................................... 70
8.9 Confirmation testing for long term data - normal safety class....................................................... 70
8.10 Use of manufacturers data or data from the literature as representative data................................ 71
8.11 Confirming material data by component testing............................................................................ 71
8.12 Comparing results from different processes and lay-ups............................................................... 72
9 Properties with damaged or nonlinearly deformed matrix................................................................. 72
9.1 Introduction.................................................................................................................................... 72
9.2 Default values ................................................................................................................................ 72
9.3 Experimental approach .................................................................................................................. 73
Sec. 5 Materials – sandwich structures...................................................................................... 75
1 General ..................................................................................................................................................... 75
1.1 Introduction.................................................................................................................................... 75
1.2 Sandwich specification .................................................................................................................. 75
1.3 Lay-up specification....................................................................................................................... 76
1.4 Isotropic/orthotropic core layers.................................................................................................... 76
1.5 Mechanical and physical properties............................................................................................... 76
1.6 Characteristic values of mechanical properties.............................................................................. 77
2 Static properties....................................................................................................................................... 77
2.1 General........................................................................................................................................... 77
2.2 Static properties ............................................................................................................................. 77
2.3 Relationship between strength and strain to failure....................................................................... 80
2.4 Characteristic values ...................................................................................................................... 80
2.5 Shear properties ............................................................................................................................. 81
2.6 Core skin interface properties ........................................................................................................ 83
3 Properties under long term static and cyclic loads .............................................................................. 83
3.1 General........................................................................................................................................... 83
3.2 Creep.............................................................................................................................................. 84
3.3 Stress rupture under permanent static loads................................................................................... 84
3.4 Static strength reduction due to permanent static loads................................................................. 84
3.5 Stress relaxation............................................................................................................................. 85
3.6 Change of modulus of elasticity under cyclic fatigue.................................................................... 85
3.7 Cycles to failure under fatigue loads ............................................................................................. 86
3.8 Static strength reduction due to cyclic loading.............................................................................. 86
3.9 Effect of high loading rates - shock loads - impact ....................................................................... 87
3.10 Characteristic values ...................................................................................................................... 87
4 Other properties ...................................................................................................................................... 88
4.1 Thermal expansion coefficient....................................................................................................... 88
4.2 Swelling coefficient for water or other liquids .............................................................................. 88
4.3 Diffusion coefficient ...................................................................................................................... 88
4.4 Thermal conductivity..................................................................................................................... 88
4.5 Friction coefficient......................................................................................................................... 88
4.6 Wear resistance .............................................................................................................................. 88
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