DNV-OS-J101

142 Pages·2009·3.34 MB·English

by  Det Norske Veritas

OFFSHORE STANDARD
DNV-OS-J101
DESIGN OF OFFSHORE WIND
TURBINE STRUCTURES
OCTOBER 2007
This booklet has since the main revision (October 2007) been amended, most recently in November 2009.
See the reference to “Amendments and Corrections” on the next page.
Section 9 is under revision w.r.t. axial capacity, see page 3 for details.
Rev.1 2009-11-25
DET NORSKE VERITAS
FOREWORD
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in relation to these functions.
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sultancy services.
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A) Qualification, Quality and Safety Methodology
B) Materials Technology
C) Structures
D) Systems
E) Special Facilities
F) Pipelines and Risers
G) Asset Operation
H) Marine Operations
J) Wind Turbines
O) Subsea Systems
Amendments and Corrections
This document is valid until superseded by a new revision. Minor amendments and corrections will be published in a separate
document normally updated twice per year (April and October).
For a complete listing of the changes, see the “Amendments and Corrections” document located at:
http://webshop.dnv.com/global/, under category “Offshore Codes”.
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Norske Veritas.
Amended November 2009 Offshore Standard DNV-OS-J101, October 2007
see note on front cover Changes – Page 3
Acknowledgments has been issued, Section 9 “Design and Construction of
Grouted Connections” in DNV-OS-J101 needs to be used with
This Offshore Standard makes use of eight figures and one
the above in mind. Until the new revised standard is in place,
table provided by Mærsk Olie og Gas AS. The eight figures
the capacity of grouted connections in offshore wind turbines
consist of Figures 11 and 12 in Section 7, Figure 1 in Appendix
will be assessed on a case-by-case basis for certification pur-
A, Figure 1 in Appendix C and Figures 1 through 4 in Appen-
poses.
dix D. The table consists of Table A1 in Appendix C. Mærsk
Olie og Gas AS is gratefully acknowledged for granting DNV • Sec.9 Design and Construction of Grouted Connections
permission to use this material.
— A new guidance note is inserted under item A101.
The standard also makes use of one figure provided by Prof.
S.K. Chakrabarti. The figure appears as Figure 7 in Sec.3. Prof.
Chakrabarti is gratefully acknowledged for granting DNV per-
mission to use this figure. General
This document supersedes the June 2004 edition.
November 2009 - Section 9 is under revision w.r.t. axial
capacity Rev.1
Main changes adopted October 2007
DNV has identified that the established industry practice for
calculating the axial load capacity of grouted connections does — Reformulation of load cases in line with Committee Draft
not fully represent their physical behaviour. In some cases this of IEC61400-3.
may result in an overestimation of calculated axial capacity of — Adjustment of safety factor requirements to reflect target
grouted connections. safety level of IEC61400-1.
— Expanded guidance for wind and wave modelling, in par-
DNV has together with the industry initiated work to achieve a
ticular for waves and wave loading in shallow waters.
better understanding of long term behaviour of grouted con-
— Rewritten section on concrete design.
nections and to establish a reliable method for estimation of
— Removal of non-technical parts and non-design parts from
axial load capacity which can be used for offshore wind turbine
the standard, i.e. commercial service descriptions and
structures. The new learning from this work will be docu-
descriptions of manufacturing surveys and instructions to
mented in a guideline, and applied as basis for revising “Off-
surveyors are removed.
shore Standard DNV-OS-J101 Design of Offshore Wind
Turbine Structures”.
Until this work is completed and a revision of DNV-OS-J101
DET NORSKE VERITAS
Offshore Standard DNV-OS-J101, October 2007 Amended November 2009
Page 4 – Changes see note on front cover
DET NORSKE VERITAS
Amended November 2009 Offshore Standard DNV-OS-J101, October 2007
see note on front cover Contents – Page 5
CONTENTS
Sec. 1 Introduction........................................................... 9 B. Wind Climate........................................................................23
B 100 Wind conditions..............................................................23
A. General....................................................................................9 B 200 Parameters for normal wind conditions..........................23
A 100 General..............................................................................9 B 300 Wind data........................................................................23
A 200 Objectives.........................................................................9 B 400 Wind modelling..............................................................24
A 300 Scope and application.......................................................9 B 500 Reference wind conditions and reference wind speeds..26
A 400 Non-DNV codes...............................................................9
C. Wave Climate.......................................................................29
B. Normative References..........................................................10 C 100 Wave parameters............................................................29
B 100 General............................................................................10 C 200 Wave data.......................................................................29
C 300 Wave modelling..............................................................30
C. Informative References.........................................................10 C 400 Reference sea states and reference wave heights...........32
C 100 General............................................................................10 C 500 Wave theories and wave kinematics...............................33
C 600 Breaking waves...............................................................35
D. Definitions............................................................................11
D 100 Verbal forms...................................................................11 D. Current..................................................................................35
D 200 Terms..............................................................................11 D 100 Current parameters..........................................................35
D 200 Current data....................................................................35
E. Abbreviations and Symbols..................................................13
D 300 Current modelling...........................................................35
E 100 Abbreviations..................................................................13
E 200 Symbols..........................................................................14 E. Water Level..........................................................................36
E 100 Water level parameters...................................................36
F. Support Structure Concepts..................................................15
E 200 Water level data..............................................................36
F 100 Introduction.....................................................................15
E 300 Water level modelling.....................................................36
F 200 Gravity-based structures and gravity-pile structures......16
F 300 Jacket-monopile hybrids and tripods..............................16 F. Ice.........................................................................................36
F 400 Monopiles.......................................................................16 F 100 Sea ice.............................................................................36
F 500 Supported monopiles and guyed towers.........................16 F 200 Snow and ice accumulation............................................36
F 600 Tripods with buckets.......................................................16 F 300 Ice modelling..................................................................36
F 700 Suction buckets...............................................................16
F 800 Lattice towers..................................................................16 G. Soil Investigations and Geotechnical Data...........................37
F 900 Low-roll floaters.............................................................17 G 100 Soil investigations...........................................................37
F 1000 Tension leg platforms.....................................................17
H. Other Site Conditions...........................................................38
Sec. 2 Design Principles................................................. 18 H 100 Seismicity.......................................................................38
H 200 Salinity............................................................................38
A. Introduction..........................................................................18 H 300 Temperature....................................................................38
A 100 General............................................................................18 H 400 Marine growth................................................................38
A 200 Aim of the design............................................................18 H 500 Air density......................................................................38
H 600 Ship traffic......................................................................38
B. General Design Conditions...................................................18 H 700 Disposed matters.............................................................39
B 100 General............................................................................18 H 800 Pipelines and cables........................................................39
C. Safety Classes and Target Safety Level...............................18 Sec. 4 Loads and Load Effects .................................... 40
C 100 Safety classes..................................................................18
C 200 Target safety...................................................................18 A. Introduction...........................................................................40
A 100 General............................................................................40
D. Limit States...........................................................................19
D 100 General............................................................................19 B. Basis for Selection of Characteristic Loads..........................40
B 100 General............................................................................40
E. Design by the Partial Safety Factor Method.........................19
E 100 General............................................................................19 C. Permanent Loads (G)............................................................40
E 200 The partial safety factor format......................................19 C 100 General............................................................................40
E 300 Characteristic load effect................................................21
E 400 Characteristic resistance.................................................21 D. Variable Functional Loads (Q).............................................40
E 500 Load and resistance factors ............................................21 D 100 General............................................................................40
D 200 Variable functional loads on platform areas...................41
F. Design by Direct Simulation of Combined Load Effect of D 300 Ship impacts and collisions............................................41
Simultaneous Load Processes...............................................21 D 400 Tank pressures................................................................41
F 100 General............................................................................21 D 500 Miscellaneous loads........................................................42
F 200 Design format.................................................................21
E. Environmental Loads (E)......................................................42
F 300 Characteristic load effect................................................21
F 400 Characteristic resistance.................................................22 E 100 General............................................................................42
E 200 Wind turbine loads..........................................................42
G. Design Assisted by Testing..................................................22 E 300 Determination of characteristic hydrodynamic loads.....48
G 100 General............................................................................22 E 400 Wave loads......................................................................48
G 200 Full-scale testing and observation of performance of E 500 Ice loads..........................................................................52
existing structures...........................................................22 E 600 Water level loads............................................................54
E 700 Earthquake loads.............................................................54
H. Probability-based Design......................................................22 E 800 Marine growth................................................................55
H 100 Definition........................................................................22 E 900 Scour...............................................................................55
H 200 General............................................................................22 E 1000 Transportation loads and installation loads....................55
Sec. 3 Site Conditions ................................................... 23 F. Combination of Environmental Loads..................................55
F 100 General............................................................................55
A. General..................................................................................23 F 200 Environmental states.......................................................56
A 100 Definition........................................................................23 F 300 Environmental contours..................................................56
DET NORSKE VERITAS
Offshore Standard DNV-OS-J101, October 2007 Amended November 2009
Page 6 – Contents see note on front cover
F 400 Combined load and load effect due to wind load and F 200 Minimum thickness.........................................................71
wave load........................................................................56 F 300 Bending and shear...........................................................71
F 500 Linear combinations of wind load and wave load..........56 F 400 Effective flange...............................................................71
F 600 Combination of wind load and wave load F 500 Effective web..................................................................72
by simulation...................................................................57 F 600 Strength requirements for simple girders........................72
F 700 Basic load cases..............................................................57 F 700 Complex girder system...................................................72
F 800 Transient load cases .......................................................59
F 900 Load combination for the fatigue limit state...................59 G. Ultimate Limit States – Slip-resistant Bolt Connections......73
G 100 General............................................................................73
G. Load Effect Analysis............................................................60
G 100 General............................................................................60 H. Ultimate Limit States – Welded Connections......................74
G 200 Global motion analysis....................................................60 H 100 General............................................................................74
G 300 Load effects in structures and foundation soils...............60 H 200 Types of welded steel joints............................................74
H 300 Weld size.........................................................................75
H. Deformation Loads...............................................................60
H 100 General............................................................................60 I. Serviceability Limit States....................................................78
H 200 Temperature loads...........................................................61 I 100 General............................................................................78
H 300 Settlements......................................................................61 I 200 Deflection criteria...........................................................78
I 300 Out-of-plane deflection of local plates............................78
Sec. 5 Load and Resistance Factors ............................ 62
J. Fatigue Limit States..............................................................78
A. Load Factors.........................................................................62 J 100 Fatigue limit state............................................................78
A 100 Load factors for the ULS................................................62 J 200 Characteristic S-N curves................................................78
A 200 Load factor for the FLS...................................................62 J 300 Characteristic stress range distribution...........................79
A 300 Load factor for the SLS...................................................62 J 400 Characteristic and design cumulative damage................81
J 500 Design fatigue factors.....................................................81
B. Resistance Factors................................................................62
J 600 Material factors for fatigue.............................................82
B 100 Resistance factors for the ULS........................................62 J 700 Design requirement.........................................................82
B 200 Resistance factors for the FLS........................................62 J 800 Improved fatigue performance of welded structures by
B 300 Resistance factors for the SLS........................................62 grinding...........................................................................82
Sec. 6 Materials.............................................................. 63 Sec. 8 Detailed Design of Offshore Concrete
Structures............................................................ 84
A. Selection of Steel Materials and Inspection Principles........63
A 100 General............................................................................63 A. General..................................................................................84
A 200 Design temperatures........................................................63
A 100 Introduction.....................................................................84
A 300 Structural category..........................................................63
A 200 Material...........................................................................84
A 400 Structural steel.................................................................64
A 300 Composite structures.......................................................84
B. Selection of Concrete Materials ..........................................66
B. Design Principles..................................................................84
B 100 General............................................................................66
B 100 Design material strength.................................................84
B 200 Material requirements.....................................................66
B 300 Concrete..........................................................................67 C. Basis for Design by Calculation...........................................85
B 400 Grout and mortar.............................................................67 C 100 Concrete grades and in-situ strength of concrete............85
B 500 Reinforcement steel.........................................................67
B 600 Prestressing steel.............................................................67 D. Bending Moment and Axial Force (ULS)............................85
D 100 General............................................................................85
C. Grout Materials and Material Testing..................................67
C 100 General............................................................................67 E. Fatigue Limit State...............................................................85
C 200 Experimental verification................................................68 E 100 General ...........................................................................85
Sec. 7 Design of Steel Structures.................................. 69 F. Accidental Limit State..........................................................85
F 100 General............................................................................85
A. Ultimate Limit States – General...........................................69
A 100 General............................................................................69 G. Serviceability Limit State.....................................................85
A 200 Structural analysis...........................................................69 G 100 Durability........................................................................85
A 300 Ductility..........................................................................69 G 200 Crack width calculation..................................................85
A 400 Yield check.....................................................................69 G 300 Other serviceability limit states.......................................86
A 500 Buckling check................................................................69
H. Detailing of Reinforcement..................................................86
B. Ultimate Limit States – Shell Structures..............................69 H 100 Positioning......................................................................86
B 100 General............................................................................69
I. Corrosion Control and Electrical Earthing...........................86
C. Ultimate Limit States – Tubular Members, Tubular Joints and I 100 Corrosion control............................................................86
Conical Transitions...............................................................70 I 200 Electrical earthing...........................................................86
C 100 General............................................................................70
J. Construction..........................................................................86
D. Ultimate Limit States – Non-Tubular Beams, Columns and J 100 General............................................................................86
Frames..................................................................................70 J 200 Inspection classes............................................................86
D 100 General............................................................................70
Sec. 9 Design and Construction of Grouted
E. Ultimate Limit States – Special Provisions for Plating and Connections......................................................... 87
Stiffeners...............................................................................70
E 100 Scope...............................................................................70 A. Introduction...........................................................................87
E 200 Minimum thickness.........................................................70 A 100 General............................................................................87
E 300 Bending of plating...........................................................70 A 200 Design principles.............................................................87
E 400 Stiffeners.........................................................................71
B. Ultimate Limit States............................................................88
F. Ultimate Limit States – Special Provisions for Girders and B 100 Connections subjected to axial load and torque..............88
Girder Systems.....................................................................71 B 200 Connections subjected to bending moment and shear
F 100 Scope...............................................................................71 loading.............................................................................89
DET NORSKE VERITAS
Amended November 2009 Offshore Standard DNV-OS-J101, October 2007
see note on front cover Contents – Page 7
C. Fatigue Limit States..............................................................90 B 200 Preparation for periodical inspections..........................105
C 100 General............................................................................90 B 300 Interval between inspections.........................................105
C 200 Connections subjected to axial load and torque..............90 B 400 Inspection results..........................................................105
C 300 Connections subjected to bending moment and shear B 500 Reporting......................................................................105
loading............................................................................90
C. Periodical Inspection of Wind Turbines ............................105
D. Requirements to Verification and Material Factors.............91 C 100 Interval between inspections.........................................105
D 100 Experimental verification...............................................91 C 200 Scope for inspection.....................................................105
D 200 Material factors for grouted connections........................91
D. Periodical Inspection of Structural and Electrical Systems
E. Grouting Operations.............................................................92 above Water .......................................................................105
E 100 General............................................................................92 D 100 Interval between inspections.........................................105
E 200 Operations prior to grouting...........................................92 D 200 Scope for inspection.....................................................106
E 300 Monitoring......................................................................92
E. Periodical Inspection of Structures Below Water...............106
Sec. 10 Foundation Design.............................................. 93 E 100 Interval between inspections.........................................106
E 200 Scope for inspection.....................................................106
A. General..................................................................................93
A 100 Introduction.....................................................................93 F. Periodical Inspection of Sea Cables...................................107
A 200 Soil investigations...........................................................93 F 100 Interval between inspections.........................................107
A 300 Characteristic properties of soil......................................93 F 200 Scope for inspection.....................................................107
A 400 Effects of cyclic loading.................................................94
A 500 Soil-structure interaction.................................................94 G. Deviations...........................................................................107
G 100 General..........................................................................107
B. Stability of Seabed................................................................94
B 100 Slope stability.................................................................94 App. A Stress Concentration Factors for
B 200 Hydraulic stability...........................................................94 Tubular Joints.................................................................. 108
B 300 Scour and scour prevention.............................................94
A. Calculation of Stress Concentration Factors.......................108
C. Pile Foundations...................................................................95
A 100 General..........................................................................108
C 100 General............................................................................95
C 200 Design criteria for monopile foundations.......................95
App. B Local Joint Flexibilities for Tubular Joints... 115
C 300 Design criteria for jacket pile foundations......................96
C 400 Design of piles subject to scour......................................97
A. Calculation of Local Joint Flexibilities...............................115
D. Gravity Base Foundations....................................................97 A 100 General..........................................................................115
D 100 General............................................................................97
D 200 Stability of foundations...................................................97 App. C Stress Concentration Factors for
D 300 Settlements and displacements.......................................98 Girth Welds...................................................................... 117
D 400 Soil reactions on foundation structure............................98
D 500 Soil modelling for dynamic analysis..............................98 A. Calculation of Stress Concentration Factors for Hot Spots117
D 600 Filling of voids................................................................98 A 100 General..........................................................................117
Sec. 11 Corrosion Protection........................................ 101 App. D Stress Extrapolation for Welds....................... 118
A. General................................................................................101
A. Stress Extrapolation to Determine Hot Spot Stresses.........118
A 100 General..........................................................................101
A 100 General..........................................................................118
B. Acceptable Corrosion Protection........................................101
App. E Tubular Connections – Fracture Mechanics
B 100 Atmospheric zone.........................................................101
B 200 Splash zone...................................................................101 Analyses and Calculations.............................................. 120
B 300 Submerged zone............................................................101
B 400 Closed compartments....................................................102 A. Stress Concentrations at Tubular Joints..............................120
A 100 General..........................................................................120
C. Cathodic Protection............................................................102
C 100 General..........................................................................102 B. Stresses at Tubular Joints....................................................120
B 100 General..........................................................................120
D. Coating................................................................................102
D 100 General..........................................................................102 C. Stress Intensity Factor.........................................................121
C 100 General..........................................................................121
Sec. 12 Transport and Installation .............................. 103 C 200 Correction factor for membrane stress component.......121
C 300 Correction factor for bending stress component...........122
A. Marine Operations..............................................................103
C 400 Crack shape and initial crack size.................................122
A 100 Warranty surveys..........................................................103
C 500 Load Shedding..............................................................122
A 200 Planning of operations..................................................103
C 600 Crack Growth ...............................................................123
A 300 Design loads..................................................................104
A 400 Structural design...........................................................104 App. F Pile Resistance and Load-displacement
A 500 Load transfer operations...............................................104
Relationships.................................................................... 124
A 600 Towing..........................................................................104
A 700 Offshore installation.....................................................104
A. Axial Pile Resistance..........................................................124
A 800 Lifting...........................................................................104
A 900 Subsea operations.........................................................104 A 100 General..........................................................................124
A 200 Clay...............................................................................124
Sec. 13 In-Service Inspection, Maintenance and A 300 Sand..............................................................................124
Monitoring......................................................... 105 A 400 t-z curves.......................................................................125
A. General................................................................................105 B. Laterally Loaded Piles........................................................125
A 100 General..........................................................................105 B 100 General..........................................................................125
B 200 Clay...............................................................................126
B. Periodical Inspections.........................................................105 B 300 Sand..............................................................................126
B 100 General..........................................................................105 B 400 Application of p-y curves.............................................127
DET NORSKE VERITAS
Offshore Standard DNV-OS-J101, October 2007 Amended November 2009
Page 8 – Contents see note on front cover
App. G Bearing Capacity Formulae for Gravity Base App. K Calculations by Finite Element Method......... 136
Foundations...................................................................... 128
A. Introduction.........................................................................136
A. Forces..................................................................................128 A 100 General..........................................................................136
A 100 General..........................................................................128
B. Types of Analysis...............................................................136
B. Correction for Torque.........................................................128 B 100 General..........................................................................136
B 200 Static analysis................................................................136
B 100 General..........................................................................128
B 300 Frequency analysis........................................................136
C. Effective Foundation Area..................................................128 B 400 Dynamic analysis..........................................................136
C 100 General..........................................................................128 B 500 Stability/buckling analysis............................................136
B 600 Thermal analysis...........................................................136
D. Bearing Capacity................................................................129 B 700 Other types of analyses.................................................136
D 100 General..........................................................................129
D 200 Bearing capacity formulae for drained conditions........129 C. Modelling............................................................................136
D 300 Bearing capacity formulae for undrained conditions, C 100 General..........................................................................136
φ = 0..............................................................................129 C 200 Model............................................................................136
C 300 Coordinate systems.......................................................136
E. Extremely Eccentric Loading.............................................129 C 400 Material properties........................................................137
E 100 General..........................................................................129 C 500 Material models.............................................................137
C 600 Elements........................................................................137
F. Sliding Resistance...............................................................130 C 700 Element types................................................................137
F 100 General..........................................................................130 C 800 Combinations................................................................137
C 900 Element size and distribution of elements....................137
App. H Cross Section Types.......................................... 131 C 1000 Element quality.............................................................138
C 1100 Boundary conditions.....................................................138
A. Cross Section Types...........................................................131 C 1200 Types of restraints.........................................................138
A 100 General..........................................................................131 C 1300 Symmetry/antimetry......................................................138
A 200 Cross section requirements for plastic analysis............131 C 1400 Loads.............................................................................139
A 300 Cross section requirements when elastic C 1500 Load application............................................................139
global analysis is used...................................................131
D. Documentation....................................................................139
App. I Extreme Wind Speed Events........................... 133 D 100 Model............................................................................139
D 200 Geometry control..........................................................139
App. J Scour at a Vertical Pile.................................... 134 D 300 Mass – volume – centre of gravity................................139
D 400 Material.........................................................................139
A. Flow around a Vertical Pile................................................134 D 500 Element type.................................................................139
D 600 Local coordinate system................................................139
A 100 General..........................................................................134
D 700 Loads and boundary conditions....................................139
B. Bed Shear Stress.................................................................134 D 800 Reactions.......................................................................139
B 100 General..........................................................................134 D 900 Mesh refinement...........................................................139
D 1000 Results...........................................................................139
C. Local Scour.........................................................................134
C 100 General..........................................................................134 App. L Ice Loads for Conical Structures.................... 141
C 200 Scour depth...................................................................134
C 300 Lateral extension of scour hole.....................................135 A. Calculation of Ice Loads.....................................................141
C 400 Time scale of scour.......................................................135 A 100 General..........................................................................141
DET NORSKE VERITAS
Amended November 2009 Offshore Standard DNV-OS-J101, October 2007
see note on front cover Sec.1 – Page 9
SECTION 1
INTRODUCTION
A. General specification of load cases. For further information, reference is
made to the Committee Draft of IEC61400-3.
A 100 General ---e-n-d---of---G-u- i-d-a-n-c-e---n-o-t-e---
101 This offshore standard provides principles, technical
107 DNV-OS-J101 is applied as part of the basis for carrying
requirements and guidance for design, construction and in-
out a DNV project certification of an offshore wind farm.
service inspection of offshore wind turbine structures.
102 DNV-OS-J101 is the DNV standard for design of off- A 200 Objectives
shore wind turbine structures. The standard covers design, 201 The standard specifies general principles and guidelines
construction, installation and inspection of offshore wind tur- for the structural design of offshore wind turbine structures.
bine structures. The design principles and overall requirements
are defined in this standard. The standard can be used as a 202 The objectives of this standard are to:
stand-alone document.
— provide an internationally acceptable level of safety by
103 The standard shall be used for design of support struc- defining minimum requirements for structures and struc-
tures and foundations for offshore wind turbines. The standard tural components (in combination with referenced stand-
shall also be used for design of support structures and founda- ards, recommended practices, guidelines, etc.)
tions for other structures in an offshore wind farm, such as — serve as a contractual reference document between suppli-
meteorological masts. ers and purchasers related to design, construction, installa-
tion and in-service inspection
The standard does not cover design of support structures and
— serve as a guideline for designers, suppliers, purchasers
foundations for transformer stations for wind farms. For design
and regulators
of support structures and foundations for transformer stations
— specify procedures and requirements for offshore struc-
DNV-OS-C101 applies.
tures subject to DNV certification
Guidance note: — serve as a basis for verification of offshore wind turbine
DNV-OS-C101 offers the choice of designing unmanned struc- structures for which DNV is contracted to perform the ver-
tures with a lower requirement to the load factor than that which ification.
applies to manned structures, hence reflecting the difference in
consequence of failure between unmanned and manned struc- A 300 Scope and application
tures. Transformer stations are usually unmanned, but the eco-
301 The standard is applicable to all types of support struc-
nomical consequences of a failure may be very large. When
support structures and foundations for transformer stations are tures and foundations for offshore wind turbines.
designed according to DNV-OS-C101, it should therefore be
302 The standard is applicable to the design of complete
considered whether it will be necessary from an economical
structures, including substructures and foundations, but
point of view to carry out the design based on the load factor
excluding wind turbine components such as nacelles and
requirement for manned structures, even if the transformer sta-
tions are unmanned. rotors.
---e-n-d---of---G-u- i-d-a-n-c-e---n-o-t-e--- 303 This standard gives requirements for the following:
— design principles
104 The standard does not cover design of wind turbine com-
— selection of material and extent of inspection
ponents such as nacelle, rotor, generator and gear box. For
structural design of rotor blades DNV-OS-J102 applies. For — design loads
structural design of wind turbine components for which no — load effect analyses
DNV standard exists, the IEC61400-1 standard applies. — load combinations
— structural design
105 The tower, which usually extends from somewhere
— foundation design
above the water level to just below the nacelle, is considered a
— corrosion protection.
part of the support structure. The structural design of the tower
is therefore covered by this standard, regardless of whether a
A 400 Non-DNV codes
type approval of the tower exists and is to be applied.
401 In case of conflict between the requirements of this
Guidance note:
standard and a reference document other than DNV docu-
For a type-approved tower, the stiffnesses of the tower form part ments, the requirements of this standard shall prevail.
of the basis for the approval. It is important to make sure not to
change the weight and stiffness distributions over the height of 402 The provision for using non-DNV codes or standards is
the tower relative to those assumed for the type approval. that the same safety level as the one resulting for designs
according to this standard is obtained.
---e-n-d---of---G-u- i-d-a-n-c-e---n-o-t-e---
403 Where reference in this standard is made to codes other
106 The standard has been written for general world-wide than DNV documents, the valid revision of these codes shall be
application. National and governmental regulations may taken as the revision which was current at the date of issue of
include requirements in excess of the provisions given by this this standard, unless otherwise noted.
standard depending on the size, type, location and intended 404 When code checks are performed according to other
service of the wind turbine structure. codes than DNV codes, the resistance and material factors as
given in the respective codes shall be used.
Guidance note:
An attempt has been made to harmonise DNV-OS-J101 with the 405 National and governmental regulations may override the
coming IEC61400-3 standard, in particular with respect to the requirements of this standard as applicable.
DET NORSKE VERITAS
Offshore Standard DNV-OS-J101, October 2007 Amended November 2009
Page 10 – Sec.1 see note on front cover
B. Normative References
Table C3 Other references
Reference Title
B 100 General
AISC LRFD Manual of Steel Construction
101 The standards in Table B1 include provisions, which
API RP 2A LRFD Planning, Designing, and Constructing Fixed
through reference in this text constitute provisions of this
Offshore Platforms – Load and Resistance
standard.
Factor Design
API RP 2N Recommended Practice for Planning,
Table B1 DNV Offshore Standards, Rules and Standards for
Designing, and Constructing Structures and
Certification Pipelines for Arctic Conditions
Reference Title BS 7910 Guide on methods for assessing the acceptabil-
DNV-OS-B101 Metallic Materials ity of flaws in fusion welded structures
DNV-OS-C101 Design of Offshore Steel Structures, BSH 7004 Standard Baugrunderkundung. Mindestenan-
General (LRFD Method) forderungen für Gründungen von Offshore-
Windenergieanlagen.
DNV-OS-C201 Structural Design of Offshore Units
(WSD method) DIN 4020 Geotechnische Untersuchungen für
bautechnische Zwecke
DNV-OS-C401 Fabrication and Testing of Offshore Structures
DIN 4021 Baugrund; Aufschluss durch Schürfe und
DNV-OS-C502 Offshore Concrete Structures
Bohrungen sowie Entnahme von Proben
DNV-OS-J102 Design and Manufacture of Wind Turbine
DIN 4131 Stählerne Antennentragwerke
Blades
DIN 4133 Schornsteine aus Stahl
Rules for Planning and Execution of Marine
Operations EN10025-1 Hot rolled products of non-alloy structural
steels
Rules for Fixed Offshore Installations
EN10025-2 Hot rolled products of structural steels. Techni-
Rules for Classification of Ships
cal delivery conditions for non-alloy structural
DNV Standard for Certification No. 2.22 steels
Lifting Appliances
EN10025-3 Hot rolled products of structural steels. Techni-
cal delivery conditions for normalized/normal-
ized rolled weldable fine grain structural steels
C. Informative References EN 10204 Metallic products – types of inspection docu-
ments
C 100 General EN10225 Weldable structural steels for fixed offshore
structures – technical delivery conditions
101 The documents in Tables C1, C2 and C3 include accept-
EN 13670-1 Execution of Concrete Structures – Part 1:
able methods for fulfilling the requirements in the standards.
Common rules
See also current DNV List of Publications. Other recognised
codes or standards may be applied provided it is shown that EN 1991-1-4 Eurocode 1: Actions on structures – Part 1-4:
General actions – wind actions
they meet or exceed the level of safety of the actual standard.
EN 1992-1-1 Eurocode 2: Design of Concrete Structures
EN 1993-1-1 Eurocode 3: Design of Steel Structures, Part 1-
Table C1 DNV Offshore Standards for structural design 1: General Rules and Rules for Buildings
Reference Title ENV 1993-1-6 Eurocode 3: Design of Steel Structures, Part 1-
DNV-OS-C501 Composite Components 6: General Rules – Supplementary Rules for the
Shell Structures
ENV 1090-1 Execution of steel structures – Part 1: General
rules and rules for buildings
Table C2 DNV Recommended Practices and Classification
ENV 1090-5 Execution of steel structures – Part 5: Supple-
Notes
mentary rules for bridges
Reference Title
prEN50308 Wind Turbines – Labour Safety
DNV/Risø Guidelines for Design of Wind Turbines
IEC61400-1 Wind Turbines – Part 1: Design Requirements
DNV-RP-B401 Cathodic Protection Design
IEC61400-3 Wind Turbines – Part 3: Design requirements
DNV-RP-C201 Buckling Strength of Plated Structures for offshore wind turbines, committee draft
DNV-RP-C202 Buckling Strength of Shells ISO6934 Steel for the prestressing of concrete
DNV-RP-C203 Fatigue Strength Analysis of Offshore Steel ISO6935 Steel for the reinforcement of concrete
Structures
ISO 12944 Paints and varnishes – Corrosion protection of
DNV-RP-C205 Environmental Conditions and Environmental steel structures by protective paint systems
Loads
ISO 14688 Geotechnical investigations and testing – iden-
DNV-RP-C207 Statistical Representation of Soil Data tification and classification of soil – Part 1:
Classification Identification and description
Buckling Strength Analysis
Notes 30.1 ISO/IEC 17020 General criteria for the operation of various
Classification types of bodies performing inspections
Foundations
Notes 30.4 ISO/IEC 17025 General requirements for the competence of
Classification Structural Reliability Analysis of Marine Struc- calibration and testing laboratories
Notes 30.6 tures ISO 19900:2002 Petroleum and natural gas industries – Offshore
Classification structures – General requirements for offshore
Fatigue Assessments of Ship Structures
Notes 30.7 structures
ISO 19901-2
Seismic design procedures and criteria
ISO 19902 Petroleum and Natural Gas Industries – Fixed
Steel Offshore Structures
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