dnv-os-c502: offshore concrete structures · det norske veritas as offshore standard dnv-os-c502,...

OFFSHORE STANDARD

The electronic p

DNV-OS-C502

Offshore Concrete StructuresSEPTEMBER 2012

DET NORSKE VERITAS AS

df version of this document found through http://www.dnv.com is the officially binding version

FOREWORDDNV is a global provider of knowledge for managing risk. Today, safe and responsible business conduct is both a licenseto operate and a competitive advantage. Our core competence is to identify, assess, and advise on risk management. Fromour leading position in certification, classification, verification, and training, we develop and apply standards and bestpractices. This helps our customers safely and responsibly improve their business performance. DNV is an independentorganisation with dedicated risk professionals in more than 100 countries, with the purpose of safeguarding life, propertyand the environment.

DNV service documents consist of among others the following types of documents: Service Specifications. Procedural requirements. Standards. Technical requirements. Recommended Practices. Guidance.

The Standards and Recommended Practices are offered within the following areas:A) Qualification, Quality and Safety MethodologyB) Materials TechnologyC) StructuresD) SystemsE) Special FacilitiesF) Pipelines and RisersG) Asset OperationH) Marine OperationsJ) Cleaner EnergyO) Subsea SystemsU) Unconventional Oil & Gas

Det Norske Veritas AS September 2012

Any comments may be sent by e-mail to [email protected]

This service document has been prepared based on available knowledge, technology and/or information at the time of issuance of this document, and is believed to reflect the best ofcontemporary technology. The use of this document by others than DNV is at the user's sole risk. DNV does not accept any liability or responsibility for loss or damages resulting fromany use of this document.

Offshore Standard DNV-OS-C502, September 2012Changes Page 3

CHANGES

GeneralThis document supersedes DNV-OS-C502, October 2010.

Text affected by the main changes in this edition is highlighted in red colour. However, if the changes involvea whole chapter, section or sub-section, normally only the title will be in red colour.

Main changes General Sections 1, 2, 3, 7 and 8 have minor changes only. Previous Appendix D Seismic Analysis (Guidelines) is deleted but included in Section 5. Previous Appendices E is new Appendix D. Previous Appendices F is new Appendix E. Appendices A, B, C, D and E have minor changes only. Appendices F, G, H and I are new.

Sec.4 Materials Rearranged text, based on the old DNV-OS-C502, but including the new materials. The design strength

values have been moved from Section 6 to this Section 4. The new materials are: structural grout, fibrereinforced structural grout, fibre reinforced concrete and fibre reinforced rods (FRP bars) replacing steelreinforcement as reinforcement in concrete structures.

Sec.5 Loads and Analyses Requirements Section is reworked completely, and harmonized with reference to ISO19903. Load factors are included in

this section. It shall be noted that for FRP reinforced members two new load combinations are introduced.These new load combinations take into account the different material factors required for long term- andshort term loading.

Sect.6 Detailed Design of Offshore Concrete Structures Section is reworded and rearranged. Material factors to be included in design are shown. For FRP bars, the material factors to be used in design

shall be determined from tests and included in the Material Certificate. The material factor for FRP willdepend on the duration of loading caused by creep fracture.

The section is changed by including design approach for the new materials covered by the standard. The section is also modified to ensure liquid tightness for oil storage containment structures following

extreme waves, earthquake or collision loads.

Sec.9 Certification and Classification This new section has been added to provide details of DNV's services relating to the application of this

standard. Notably certification schemes for FRP bars and Structural Grout are detailed.

Corrections and ClarificationsIn addition to above stated main changes, a number of corrections and clarifications may have been made tothe existing text.


Offshore Standard DNV-OS-C502, September 2012 Contents Page 4

CONTENTS

Sec. 1 Introduction ...................................................................................................................................... 12A. General .......................................................................................................................................................................... 12A 100 Introduction......................................................................................................................................................... 12A 200 Objective ............................................................................................................................................................. 12A 300 Scope and applications........................................................................................................................................ 12A 400 Codes and standards other than DNV standard .................................................................................................. 13A 500 Classification ...................................................................................................................................................... 13A 600 Certification ........................................................................................................................................................ 13

B. References ..................................................................................................................................................................... 13B 100 General................................................................................................................................................................ 13B 200 Normative references ......................................................................................................................................... 13B 300 Informative references ........................................................................................................................................ 14

C. Definitions..................................................................................................................................................................... 15C 100 Verbal forms ....................................................................................................................................................... 15C 200 Terms .................................................................................................................................................................. 15C 300 Terms (continued)............................................................................................................................................... 19

D. Abbreviations and Symbols .......................................................................................................................................... 20D 100 Abbreviations...................................................................................................................................................... 20D 200 Symbols .............................................................................................................................................................. 21

Sec. 2 Safety Philosophy ............................................................................................................................. 26A. General .......................................................................................................................................................................... 26A 100 Objective ............................................................................................................................................................. 26A 200 Systematic review ............................................................................................................................................... 26A 300 Safety class methodology ................................................................................................................................... 26A 400 Quality assurance ................................................................................................................................................ 27A 500 Health, safety and environment .......................................................................................................................... 27A 600 Qualifications of personnel ................................................................................................................................. 27

B. Design Format............................................................................................................................................................... 27B 100 General................................................................................................................................................................ 27

C. Identification of Major Accidental Hazards.................................................................................................................. 28C 100 General................................................................................................................................................................ 28

D. Life extensions .............................................................................................................................................................. 29D 100 General................................................................................................................................................................ 29

Sec. 3 Design Documentation ..................................................................................................................... 30A. General .......................................................................................................................................................................... 30A 100 Introduction......................................................................................................................................................... 30A 200 Overall Planning ................................................................................................................................................. 30A 300 Documentation required in the planning stage ................................................................................................... 30A 400 Documentations required prior to construction .................................................................................................. 32A 500 AS-BUILT documentation .............................................................................................................................. 33A 600 Inspection/monitoring plans for structure in service .......................................................................................... 33

Sec. 4 Materials ........................................................................................................................................... 34A. General .......................................................................................................................................................................... 34A 100 General................................................................................................................................................................ 34

B. Concrete/Grout Constituents......................................................................................................................................... 34B 100 General................................................................................................................................................................ 34B 200 Cement ................................................................................................................................................................ 34B 300 Mixing water....................................................................................................................................................... 35B 400 Normal weight aggregates .................................................................................................................................. 36B 500 Lightweight aggregates....................................................................................................................................... 36B 600 Additions............................................................................................................................................................. 36B 700 Admixtures.......................................................................................................................................................... 37

C. Concrete ........................................................................................................................................................................ 37C 100 Concrete categorization ...................................................................................................................................... 37C 200 Concrete mix....................................................................................................................................................... 37C 300 Concrete characteristic strength ......................................................................................................................... 38



D. Fibre Reinforced Concrete ............................................................................................................................................ 41D 100 Material requirements of fibre reinforced concrete ............................................................................................ 41

E. Structural Grout............................................................................................................................................................. 43E 100 Material requirements ......................................................................................................................................... 43E 200 Pre-packed blended grout ................................................................................................................................... 45

F. Fibre Reinforced Structural Grout ................................................................................................................................ 45F 100 Material requirements for fibre reinforced structural grout................................................................................ 45F 200 Pre-packed blended grout with fibres ................................................................................................................. 47

G. Steel Reinforcement ...................................................................................................................................................... 47G 100 General................................................................................................................................................................ 47G 200 Mechanical splices and end anchorages for reinforcement ................................................................................ 47G 300 Approval of welding procedures......................................................................................................................... 48G 400 Steel reinforcement characteristic strength ........................................................................................................ 48

H. Steel Prestressing Reinforcement.................................................................................................................................. 48H 100 General................................................................................................................................................................ 48H 200 Components for the prestressing system ............................................................................................................ 48H 300 Steel prestressing reinforcement characteristic strength .................................................................................... 48

I. FRP Reinforcement....................................................................................................................................................... 48I 100 General................................................................................................................................................................ 48I 200 Mechanical splices and anchorages for FRP reinforcements ............................................................................. 49I 300 FRP prestressed bars ........................................................................................................................................... 49I 400 FRP reinforcement characteristic strength.......................................................................................................... 49

J. Steel Fibres.................................................................................................................................................................... 50J 100 General................................................................................................................................................................ 50

K. FRP Fibres..................................................................................................................................................................... 50K 100 General................................................................................................................................................................ 50

L. Embedded Materials ..................................................................................................................................................... 50L 100 General................................................................................................................................................................ 50

M. Other Materials ............................................................................................................................................................. 50M 100 Repair materials .................................................................................................................................................. 50M 200 Non-cementitious materials ................................................................................................................................ 50M 300 Equivalent materials ........................................................................................................................................... 51

N. Testing of Materials ...................................................................................................................................................... 51N 100 Testing of freshly mixed concrete....................................................................................................................... 51N 200 Testing of concrete in the structure..................................................................................................................... 51N 300 Grout for prestressing tendons ............................................................................................................................ 51N 400 Pre-packed blended grout ................................................................................................................................... 51N 500 Reinforcement steel ............................................................................................................................................ 51N 600 Prestressing steel................................................................................................................................................. 51N 700 Mechanical splices for reinforcement................................................................................................................. 51N 800 Components for the prestressing system ............................................................................................................ 51N 900 Welding procedures ............................................................................................................................................ 51N 1000 Testing of repair materials .................................................................................................................................. 51N 1100 Testing of FRP materials .................................................................................................................................... 51

Sec. 5 Loads and Analyses Requirements ................................................................................................. 52A. Requirements to Design ................................................................................................................................................ 52A 100 General................................................................................................................................................................ 52A 200 Site related functional requirements and environmental considerations ............................................................ 52A 300 Facility operational requirements ....................................................................................................................... 52A 400 Structural requirements....................................................................................................................................... 52A 500 Materials requirements........................................................................................................................................ 53A 600 Execution requirements ...................................................................................................................................... 53A 700 Temporary phases requirements ......................................................................................................................... 53

B. Design principles........................................................................................................................................................... 53B 100 General................................................................................................................................................................ 53B 200 Design loads........................................................................................................................................................ 54B 300 Design resistance ................................................................................................................................................ 54

C. Load and Load Effects .................................................................................................................................................. 54C 100 General................................................................................................................................................................ 54C 200 Environmental loads ........................................................................................................................................... 55C 300 Functional loads .................................................................................................................................................. 56C 400 Accidental loads.................................................................................................................................................. 56



D. Load Combinations and Partial Safety Factors............................................................................................................. 58D 100 Partial load factors, f.......................................................................................................................................... 58D 200 Combinations of loads ........................................................................................................................................ 60D 300 Consequence of failure ....................................................................................................................................... 60

E. Structural Analysis ........................................................................................................................................................ 60E 100 General................................................................................................................................................................ 60E 200 Youngs modulus to be used in load effect analyses .......................................................................................... 62E 300 Effects of temperature, shrinkage, creep and relaxation..................................................................................... 63E 400 Special load effects ............................................................................................................................................. 64E 500 Physical representation ....................................................................................................................................... 64E 600 Loads................................................................................................................................................................... 65E 700 Mass simulation .................................................................................................................................................. 65E 800 Damping.............................................................................................................................................................. 65E 900 Linear elastic static analysis................................................................................................................................ 65E 1000 Dynamic analysis ................................................................................................................................................ 65E 1100 Pseudo-static analysis ......................................................................................................................................... 65E 1200 Non-linear analysis ............................................................................................................................................. 65E 1300 Probabilistic analysis .......................................................................................................................................... 65E 1400 Reliability analysis.............................................................................................................................................. 66E 1500 Analyses requirements ........................................................................................................................................ 66E 1600 Analysis of construction stages........................................................................................................................... 66E 1700 Transportation analysis ....................................................................................................................................... 66E 1800 Installation and deck mating analysis ................................................................................................................. 67E 1900 In-service strength and serviceability analyses................................................................................................... 67E 2000 Fatigue analysis................................................................................................................................................... 67E 2100 Seismic analysis .................................................................................................................................................. 67E 2200 Accidental and overload analyses....................................................................................................................... 67E 2300 Platform removal/reuse....................................................................................................................................... 68

F. Topside Interface Design .............................................................................................................................................. 68F 100 Introduction......................................................................................................................................................... 68F 200 Basis for design................................................................................................................................................... 68F 300 Deck/shaft structural connection......................................................................................................................... 69F 400 Topsides - substructures mating ......................................................................................................................... 69F 500 Transportation ..................................................................................................................................................... 69

G. Barges............................................................................................................................................................................ 69G 100 General................................................................................................................................................................ 69

Sec. 6 Detailed Design of Offshore Concrete Structures ......................................................................... 70A. General .......................................................................................................................................................................... 70A 100 Introduction......................................................................................................................................................... 70A 200 Material ............................................................................................................................................................... 70A 300 Load effects......................................................................................................................................................... 70A 400 Effective flange width......................................................................................................................................... 70A 500 Composite structures........................................................................................................................................... 71A 600 Prestressed structures with unbonded tendons.................................................................................................... 71A 700 Yield line theory ................................................................................................................................................. 72

B. Design Principles .......................................................................................................................................................... 72B 100 General................................................................................................................................................................ 72B 200 Limit states.......................................................................................................................................................... 72B 300 Characteristic values for material strength ......................................................................................................... 73B 400 Partial safety factors for materials ...................................................................................................................... 73B 500 Design by testing ................................................................................................................................................ 73

C. Basis for Design by Calculation.................................................................................................................................... 73C 100 Design material strength ..................................................................................................................................... 73C 200 Stress strain curve for structural grout and fibre reinforced grout...................................................................... 79C 300 Steel reinforcement stress strain curves .......................................................................................................... 79C 400 FRP reinforcement stress strain curves............................................................................................................ 80C 500 Geometrical dimensions in the calculation of sectional capacities..................................................................... 80C 600 Tension in structural members............................................................................................................................ 81C 700 Creep effects ....................................................................................................................................................... 81C 800 Effect of water pressure ...................................................................................................................................... 81

D. Bending Moment and Axial Force (ULS)..................................................................................................................... 81D 100 General................................................................................................................................................................ 81

E. Slender Structural Members.......................................................................................................................................... 82E 100 General................................................................................................................................................................ 82



F. Shear Forces in Beams and Slabs ................................................................................................................................. 84F 100 Basis.................................................................................................................................................................... 84F 200 Simplified method............................................................................................................................................... 85F 300 Truss model method............................................................................................................................................ 87F 400 Additional force in the longitudinal reinforcement from shear force ................................................................. 87F 500 Slabs subjected to concentrated actions.............................................................................................................. 88

G. Torsional Moments in Beams ....................................................................................................................................... 90G 100 General................................................................................................................................................................ 90

H. General Design Method for Structural Members Subjected to In-plane Forces........................................................... 91H 100 General................................................................................................................................................................ 91H 200 Membrane (in-plane) shear resistance ................................................................................................................ 92

I. Regions with Discontinuity in Geometry or Loads ...................................................................................................... 94I 100 General................................................................................................................................................................ 94

J. Shear Forces in Construction Joints.............................................................................................................................. 94J 100 General................................................................................................................................................................ 94

K. Bond Strength and Anchorage Failure.......................................................................................................................... 95K 100 General................................................................................................................................................................ 95

L. Partially Loaded Areas................................................................................................................................................ 100L 100 General.............................................................................................................................................................. 100

M. Fatigue Limit State...................................................................................................................................................... 102M 100 General.............................................................................................................................................................. 102M 200 Fatigue strength, design life.............................................................................................................................. 103M 300 Bending moment and axial force ...................................................................................................................... 104M 400 Shear force ........................................................................................................................................................ 105M 500 Anchorage and splicing..................................................................................................................................... 105

N. Accidental Limit State ................................................................................................................................................ 106N 100 General.............................................................................................................................................................. 106N 200 Explosion and impact........................................................................................................................................ 106N 300 Fire .................................................................................................................................................................... 106

O. Serviceability Limit State............................................................................................................................................ 107O 100 General.............................................................................................................................................................. 107O 200 Durability .......................................................................................................................................................... 107O 300 Crack width limitations..................................................................................................................................... 108O 400 Displacements ................................................................................................................................................... 109O 500 Vibrations.......................................................................................................................................................... 110O 600 Tightness against leakages of fluids ................................................................................................................. 110O 700 Tightness against leakage of gas....................................................................................................................... 110O 800 Crack width calculation .................................................................................................................................... 110O 900 Limitation of stresses in prestressed structures................................................................................................. 112O 1000 Freeze/thaw cycles ............................................................................................................................................ 112O 1100 Temperature effects .......................................................................................................................................... 112O 1200 Deflection prediction for FRP reinforced concrete members .......................................................................... 112

P. Design by Testing ....................................................................................................................................................... 113P 100 General.............................................................................................................................................................. 113P 200 The test specimen.............................................................................................................................................. 113P 300 Design actions................................................................................................................................................... 113P 400 Test procedure................................................................................................................................................... 113P 500 Processing of the test results ............................................................................................................................. 114P 600 Test report ......................................................................................................................................................... 114

Q. Rules for Detailing of Reinforcement ......................................................................................................................... 115Q 100 Positioning ....................................................................................................................................................... 115Q 200 Concrete cover .................................................................................................................................................. 115Q 300 Splicing ............................................................................................................................................................. 116Q 400 Bending of steel reinforcing bars...................................................................................................................... 117Q 500 Bending of FRP bars......................................................................................................................................... 118Q 600 Minimum area of reinforcement - General ....................................................................................................... 118Q 700 Minimum area of reinforcement - slabs/plates ................................................................................................. 118Q 800 Minimum area of reinforcement - flat slabs ..................................................................................................... 119Q 900 Minimum area of reinforcement - beams.......................................................................................................... 120Q 1000 Minimum area of reinforcement - columns ...................................................................................................... 121Q 1100 Minimum area of reinforcement - walls ........................................................................................................... 122Q 1200 Minimum area of reinforcement - reinforced foundations ............................................................................... 123Q 1300 Minimum area of reinforcement - prestressed structures ................................................................................. 123



R. Corrosion Control ....................................................................................................................................................... 123R 100 General.............................................................................................................................................................. 123R 200 Corrosion zones and environmental parameters .............................................................................................. 124R 300 Forms of corrosion and associated corrosion rates ........................................................................................... 124R 400 Cathodic protection........................................................................................................................................... 124

S. Design of Fibre Reinforced Concrete Members ......................................................................................................... 125S 100 General.............................................................................................................................................................. 125

T. Design of Structural Members made of Grout............................................................................................................ 125T 100 General.............................................................................................................................................................. 125T 200 Design for strength in ULS and ALS................................................................................................................ 126T 300 Design for fatigue life ....................................................................................................................................... 126T 400 FE Analyses of grouted connections................................................................................................................. 127T 500 Fibre reinforced grout ....................................................................................................................................... 127T 600 Type A steel to steel connections with grout .................................................................................................... 127T 700 Type B steel to concrete connection ................................................................................................................. 128T 800 Type C concrete to concrete connection........................................................................................................... 128T 900 Type D connecting two precast concrete elements with in-situ cast structural grout connection ................... 129

Sec. 7 Construction ................................................................................................................................... 130A. General ........................................................................................................................................................................ 130A 100 Application........................................................................................................................................................ 130A 200 Codes and standards.......................................................................................................................................... 130A 300 Scope................................................................................................................................................................. 130

B. Definitions................................................................................................................................................................... 130B 100 Terms ................................................................................................................................................................ 130

C. Documentation ............................................................................................................................................................ 130C 100 General.............................................................................................................................................................. 130

D. Quality Control - Inspection, Testing and Corrective Actions ................................................................................... 130D 100 General.............................................................................................................................................................. 130D 200 Inspection Classes............................................................................................................................................. 131D 300 Inspection of materials and products ................................................................................................................ 131D 400 Inspection of execution ..................................................................................................................................... 131

E. Construction Planning................................................................................................................................................. 133E 100 General.............................................................................................................................................................. 133

F. Materials and Material Testing ................................................................................................................................... 134F 100 General.............................................................................................................................................................. 134F 200 Constituent Materials ........................................................................................................................................ 134F 300 Reinforcement and prestressing system components ....................................................................................... 135F 400 Production and on-site quality control testing .................................................................................................. 136F 500 Testing of concrete in the structure................................................................................................................... 137F 600 Non-cementitious materials .............................................................................................................................. 137

G. Formwork.................................................................................................................................................................... 137G 100 Design, materials and erection.......................................................................................................................... 137G 200 Slip-form systems ............................................................................................................................................. 138G 300 Jump-forming systems ...................................................................................................................................... 138G 400 Inserts in formwork, recesses and blockouts .................................................................................................... 138G 500 Removal of formwork and falsework ............................................................................................................... 139G 600 Surface treatment and final preparation............................................................................................................ 139

H. Reinforcement and Embedded Steel ........................................................................................................................... 139H 100 Reinforcement................................................................................................................................................... 139H 200 Prestressing ducts and anchorages .................................................................................................................... 140H 300 Embedded steel ................................................................................................................................................. 141H 400 Inspection and survey ....................................................................................................................................... 141

I. Production of Concrete and Grout .............................................................................................................................. 142I 100 General.............................................................................................................................................................. 142

J. Transport, Casting, Compaction and Curing of Concrete........................................................................................... 142J 100 Transport ........................................................................................................................................................... 142J 200 Casting and compaction.................................................................................................................................... 143J 300 Curing ............................................................................................................................................................... 144J 400 Completion........................................................................................................................................................ 144

K. Completion of Prestressing Systems........................................................................................................................... 145K 100 Threading and stressing of tendons................................................................................................................... 145K 200 Tensioning of tendons....................................................................................................................................... 145



K 300 Pre-tensioning ................................................................................................................................................... 145K 400 Post-tensioning.................................................................................................................................................. 146K 500 Protective measures, grouting, greasing, concreting ........................................................................................ 146K 600 Unbonded tendons ............................................................................................................................................ 146K 700 Grouting of ducts .............................................................................................................................................. 146K 800 Greasing operations .......................................................................................................................................... 147

L. Repairs ........................................................................................................................................................................ 147L 100 General.............................................................................................................................................................. 147

M. Corrosion Protection ................................................................................................................................................... 147M 100 General.............................................................................................................................................................. 147

N. Site Records and As-built Documentation.................................................................................................................. 147N 100 General.............................................................................................................................................................. 147

O. Precast Concrete Elements.......................................................................................................................................... 148O 100 General.............................................................................................................................................................. 148O 200 Handling and storage ........................................................................................................................................ 148O 300 Placing and adjustment ..................................................................................................................................... 148O 400 Jointing and completion works ......................................................................................................................... 148

P. Geometrical Tolerances .............................................................................................................................................. 149P 100 General.............................................................................................................................................................. 149P 200 Reference system .............................................................................................................................................. 149P 300 Member tolerances (Guidelines)....................................................................................................................... 149P 400 Cross-sectional tolerances (Guidelines)............................................................................................................ 150P 500 Embedments and penetrations (Guidelines) ..................................................................................................... 150

Q. Grouting Operations.................................................................................................................................................... 151Q 100 General.............................................................................................................................................................. 151

Sec. 8 In-service Inspection, Maintenance and Conditional Monitoring............................................. 152A. General ........................................................................................................................................................................ 152A 100 Application........................................................................................................................................................ 152A 200 Scope................................................................................................................................................................. 152A 300 Personnel qualifications .................................................................................................................................... 152A 400 Planning ............................................................................................................................................................ 152A 500 Programme for inspection and condition monitoring ....................................................................................... 153A 600 Inspection and condition monitoring milestones and intervals ........................................................................ 153A 700 Documentation.................................................................................................................................................. 153A 800 Important items related to inspection and condition monitoring ...................................................................... 154A 900 Corrosion protection ......................................................................................................................................... 155A 1000 Inspection and condition monitoring types....................................................................................................... 156A 1100 Marking............................................................................................................................................................. 156A 1200 Guidance for inspection of special areas .......................................................................................................... 156

Sec. 9 Certification and Classification .................................................................................................... 159A. General ........................................................................................................................................................................ 159A 100 Application ....................................................................................................................................................... 159A 200 Certification and classification principles......................................................................................................... 159A 300 Assumptions...................................................................................................................................................... 159A 400 Documentation requirements ............................................................................................................................ 159A 500 Certificate types ................................................................................................................................................ 159A 600 Requirements to Certification ........................................................................................................................... 160

B. Classification of Offshore Structures .......................................................................................................................... 160B 100 General.............................................................................................................................................................. 160B 200 Materials ........................................................................................................................................................... 160B 300 Certification of materials .................................................................................................................................. 160

C. Classification of Concrete Barges............................................................................................................................... 161C 100 General.............................................................................................................................................................. 161C 200 Materials ........................................................................................................................................................... 161C 300 Certification of materials .................................................................................................................................. 161

D. Certification of FRP Reinforcement (NV).................................................................................................................. 161D 100 General ............................................................................................................................................................. 161D 200 Material testing ................................................................................................................................................. 161D 300 Manufacturing site approval ............................................................................................................................. 161D 400 Award of certificate .......................................................................................................................................... 162D 500 Maintenance of certificate................................................................................................................................. 162



E. Certification of Structural Grout (NV)........................................................................................................................ 162E 100 General.............................................................................................................................................................. 162E 200 Material testing ................................................................................................................................................. 162E 300 Approval of supporting documentation and mock up testing........................................................................... 163E 400 Manufacturing site approval ............................................................................................................................. 163E 500 Award of certificate .......................................................................................................................................... 164E 600 Maintenance of certificate................................................................................................................................. 164

App. A Environmental Loading (Guidelines) ........................................................................................... 165

A. General ........................................................................................................................................................................ 165A 100 Environmental Loads ........................................................................................................................................ 165A 200 Extreme wave loads .......................................................................................................................................... 165A 300 Diffraction analysis........................................................................................................................................... 166A 400 Additional requirements for dynamic analysis under wave load...................................................................... 166A 500 Model testing .................................................................................................................................................... 166A 600 Current load ...................................................................................................................................................... 167A 700 Wind loads ........................................................................................................................................................ 168

App. B Structural Analyses Modelling (Guidelines)............................................................................. 169

A. General ........................................................................................................................................................................ 169A 100 Physical representation ..................................................................................................................................... 169A 200 Loads................................................................................................................................................................. 170A 300 Mass simulation ................................................................................................................................................ 171A 400 Damping............................................................................................................................................................ 171

App. C Structural Analyses (Guidelines) .................................................................................................. 172

A. General ........................................................................................................................................................................ 172A 100 Linear elastic static analysis.............................................................................................................................. 172A 200 Dynamic analysis .............................................................................................................................................. 172A 300 Pseudo-static analysis ....................................................................................................................................... 173A 400 Non-linear analysis ........................................................................................................................................... 173

App. D Use of Alternative Detailed Design Standard (Guidelines) ....................................................... 175

A. General ........................................................................................................................................................................ 175A 100 Introduction....................................................................................................................................................... 175A 200 Conditions ......................................................................................................................................................... 175

App. E Crack width Calculation (Guidelines).......................................................................................... 177

A. Steel reinforced structures........................................................................................................................................... 177A 100 Introduction....................................................................................................................................................... 177A 200 Stabilized crack pattern..................................................................................................................................... 177A 300 Distance between cracks with deviations between the principle strain directions and the direction of the

reinforcement .................................................................................................................................................... 178A 400 General Method ................................................................................................................................................ 178A 500 Simplified Approach......................................................................................................................................... 178

B. FRP reinforced structures............................................................................................................................................ 178

App. F Requirements to Content in Material Certificates for FRP Bars .............................................. 181

A. General ........................................................................................................................................................................ 181A 100 Minimum requirements..................................................................................................................................... 181

B. Testing of Materials .................................................................................................................................................... 182B 100 Recommended testing....................................................................................................................................... 182B 200 Requirements of testing .................................................................................................................................... 182

App. G QA/QC System for Manufacture of FRP Bars (Guidelines) ...................................................... 184

A. General ........................................................................................................................................................................ 184A 100 Minimum documentation.................................................................................................................................. 184A 200 Physical properties of bars ................................................................................................................................ 186

App. H Requirements to Content in Material Certificate for Structural Grout ................................... 188

A. General ........................................................................................................................................................................ 188A 100 Minimum requirements..................................................................................................................................... 188

B. Testing of Materials .................................................................................................................................................... 189B 100 Recommended testing....................................................................................................................................... 189



B 200 Requirements of testing .................................................................................................................................... 191

C. Supporting Documentation ......................................................................................................................................... 192C 100 Minimum requirements..................................................................................................................................... 192

App. I QA/QC System for Manufacture of Structural Grout, or Equivalent Material (Guidelines) 194

A. General ........................................................................................................................................................................ 194A 100 Minimum requirements .................................................................................................................................... 194


Offshore Standard DNV-OS-C502, September 2012 Sec.1 Page 12

SECTION 1INTRODUCTION

A. GeneralA 100 Introduction101 This offshore standard provides principles, technical requirements and guidelines for the design,construction and in service inspection of Offshore Concrete Structures. The Concrete Structures may befloating or ground supported structures.102 This standard shall be used together with the general offshore design standards for steel structures DNV-OS-C101, DNV-OS-C102, DNV-OS-C103, DNV-OS-C105 and DNV-OS-C106. These standards cover awide range of different structures.103 The standard covers design, fabrication/construction, installation and inspection of Offshore ConcreteStructures.104 For design and construction of offshore concrete wind turbines, reference is made to DNV-OS-J101Design of Offshore Wind Turbines Structures.105 For design and construction of LNG terminal structures and containment systems, reference is made toDNV-OS-C503 Concrete LNG Terminal Structures and Containment Systems.106 This standard covers design of fixed and floating platforms/structures for oil production and oil storageand barges where reinforced and prestressed concrete is used as structural material.107 To provide manufacturers, which are currently supplying grouts for DNV Certified and/or Verifiedprojects, time to attain certification for their products; the requirements included here-in for MaterialCertificates for grout and equivalent materials shall not come into effect until 1st January 2014.

A 200 Objective201 The objectives of this standard are to:

Provide an international standard for the design, construction and in-service inspection of OffshoreConcrete Structures with an acceptable level of safety by defining minimum requirements for design,construction control and in-service inspection.

Serve as a contractual reference document between supplier and purchasers related to design, constructionand in-service inspection.

Serve as a guideline for designer, supplier, purchasers and regulators.

A 300 Scope and applications301 The standard is applicable to design, construction, inspection and maintenance of Offshore ConcreteStructures, using structural concrete and reinforcement, as defined in Section 4, as the structural material in thesupport structure, as defined in 302 below.302 The standard can be used in the structural design of the following types of support structures, which arereferred in this standard as Offshore Concrete Structures:

Gravity Based Structures (GBS) for oil/gas production offshore. GBS for oil/gas production with oil storage facility. GBS for offshore and onshore wind turbine foundations. Floating concrete structures for production of oil/gas. The structure may be of any type: floating structure,

i.e. Tension leg platform (TLP), column stabilised units and barge type units. Deep water caisson type concrete foundation of bridges. Floating foundations for bridges, parking houses or storage buildings.

303 Appendices A to E contain guidelines for the design of Offshore Concrete Structures.304 Floating Offshore Concrete Structures shall be designed with freeboard and intact stability in accordancewith DNV-OS-C301. For temporary phases the stability shall be in accordance with DNV Rules for Planningand Execution of Marine Operations.305 The development and design of new concepts for Offshore Concrete Structures requires a systematichazard identification process in order to mitigate the risk to an acceptable risk level. Hazard identification istherefore a central tool in this standard for this purpose.306 Appendix F contains requirements for the contents of the Material Certificate for FRP bars.307 Appendix G contains QA/QC system for manufacture of FRP bars.308 Appendix H contains requirements for the Material Certificate of structural grout and fibre reinforcedstructural grout.



309 Appendix I contains QA/QC system for manufacture of structural grout and fibre reinforced structuralgrout.

A 400 Codes and standards other than DNV standard401 In case of conflict between the requirements of DNV standard and a reference document other than DNVstandard, the requirement of DNV standard shall prevail.402 The provision for using codes or standards other than DNV is that the same safety level as provided bythis DNV standard is obtained.403 Where reference is made to codes and standards other than DNV, the valid revision shall be taken as therevision which is current at the date of issue of this standard, unless otherwise noted.404 In addition to the requirements mentioned in this standard, it is also the responsibility of the designer,owner and operator to comply with additional requirements that may be imposed by the flag state or the coastalstate or any other jurisdictions in the intended area of deployment and operation.

A 500 Classification501 Classification principles, procedures and application of class notations related to classification servicesof offshore units are specified in the DNV Offshore Service Specifications given in Table A1.

502 See Section 9 for details of DNV services with regard to the classification of Concrete Barges.

A 600 Certification601 See Section 9 for details of DNV services.

B. References

B 100 General101 In this standard, when dated references are presented, only the edition cited applies. For undatedreferences, the latest edition of the referenced document (including amendments) applies.

B 200 Normative references 201 The standards in Table B1 include provisions, which through reference in this text constitute provisionsof this standard.

Table A1 DNV Offshore Service SpecificationsReference Title

DNV-OSS-101 Rules for Classification of Offshore Drilling and Support Units DNV-OSS-102 Rules for Classification of Floating Production and Storage UnitsDNV-OSS-103 Rules for Classification of LNG/LPG Floating Production and Storage Units or InstallationsDNV-OSS-121 Classification Based on Performance Criteria Determined by Risk Assessment MethodologyDNV-OSS-304 Risk Based Verification of Offshore StructuresDNV-OSS-309 Verification, certification and classification of gas export and receiving terminalsDNV-OSS-401 Technology Qualification Management

Table B1 DNV Rules and Offshore StandardsReference Title

DNV Rules Rules for Classification of Ships Pt.5 Ch.7 Sec.14 Concrete BargesDNV Rules DNV Rules for Planning and Execution of Marine OperationsDNV-OS-A101 Safety Principles and ArrangementDNV-OS-C101 Design of Offshore Steel Structures, General (LRFD Method)DNV-OS-C102 Structural Design of Offshore ShipsDNV-OS-C103 Structural Design of Column-stabilised Units (LRFD method)DNV-OS-C105 Structural Design of TLPS (LRFD method)DNV-OS-C106 Structural Design of Deep Draught Floating Units/Spars (LRFD and WSD Method)DNV-OS-C301 Stability and Watertight IntegrityDNV-OS-C503 Concrete LNG Terminal Structures and Containment SystemsDNV-OS-J101 Design of Offshore Wind Turbine Structures



B 300 Informative references301 The latest valid revision of the documents in Table B2, Table B3 and Table B4 apply. These includeacceptable methods for fulfilling the requirements in this standard. See also current DNV List of Publications.302 Other recognised codes or standards may be applied provided it is documented that they meet or exceedthe level of safety of this DNV Offshore Standard, reference is made to Appendix D.

Table B2 DNV Rules and Offshore Object Standards for Structural DesignReference Title

DNV Rules Rules for Classification of Ships. Pt.5 Ch.5 Liquefied Gas CarriersDNV-OS-B101 Metallic MaterialsDNV-OS-C401 Fabrication and Testing of Offshore StructuresDNV-OS-E301 Position MooringDNV-OS-J102 Offshore Substations for Wind Farms

Table B3 DNV Recommended Practices and Classification NotesReference Title

DNV-RP-C201 Buckling Strength of Plated StructuresDNV-RP-C202 Buckling Strength of ShellsDNV-RP-C203 Fatigue Strength Analysis of Offshore Steel StructuresDNV-RP-C205 Environmental Conditions and Environmental LoadsDNV-RP-E301 Design and Installation of Fluke Anchors in ClayDNV-RP-E302 Design and Installation of Plate Anchors in ClayClassification Note 30.1 Buckling Strength Analysis of Bars and Frames, and Spherical Shells Section 2 Bars and

FramesClassification Note 30.4 FoundationsClassification Note 30.6 Structural Reliability Analysis of Marine StructuresClassification Note 30.7 Fatigue Assessments of Ship Structures

Table B4 Other referencesReference Title

ACI 440.1R-06 Guide for the design and construction of structural concrete reinforced with FRP barsACI 440.3R-04 Guide test methods for fibre-reinforced polymers (FRPs) for reinforcing or strengthening concrete

structuresACI 440-4R 04 Prestressing Concrete Structures with FRP TendonsACI 440R-07 Report on fibre-reinforced polymer (FRP) reinforcement for concrete structures. ASTM C150 Standard Specification for Portland CementASTM C157 Standard Test Method for Length Change of Hardened Hydraulic-Cement Mortar and ConcreteASTM C191 Standard Test method for Time of Setting of Hydraulic Cement by Vicat NeedleASTM C230 Standard Specification for Flow Table for Use in Tests of Hydraulic CementASTM C348 Standard Test Method for Flexural Strength of Hydraulic Cement MortarsASTM C403 Standard Test Method for Time of Setting of Concrete Mixtures by Penetration ResistanceASTM C457 Standard Test Method for Microscopical Determination of Parameters of the Air-Void System in

Hardened ConcreteASTM C469 Standard Test Method for Static Modulus of Elasticity and. Poisson's Ratio of Concrete in

CompressionASTM C490 Standard Practice for Use of Apparatus for the Determination of Length Change of Hardened

Cement Paste, Mortar, and ConcreteASTM C512 Standard Test Method for Creep of Concrete in CompressionASTM C940 Standard Test Method for Expansion and Bleeding of Freshly Mixed Grouts for Preplaced-

Aggregate Concrete in the LaboratoryCSA S806-12 Design and construction of building structures with fibre-reinforced polymersEN 12350-6 Testing fresh concrete - Part 6: Density EN 12350-7 Testing fresh concrete - Part 7: Air content - pressure methodsEN 12350-8 Testing fresh concrete - Part 8: Self-compacting concrete - Slump flow testEN 12390-3 Testing hardened concrete - Part 3: Compressive strength of test specimens EN 12390-7 Testing hardened concrete - Part 7: Density of hardened concrete



C. DefinitionsC 100 Verbal forms101 Shall: Indicates a mandatory requirement to be followed for fulfilment or compliance with the presentstandard. Deviations are not permitted unless formally and rigorously justified, and accepted by all relevantcontracting parties.102 Should: Indicates a recommendation that a certain course of action is preferred or particularly suitable.Alternative courses of action are allowable under the standard where agreed between contracting parties butshall be justified and documented.103 May: Indicates a permission, or an option, which is permitted as part of conformance with the standard.

C 200 Terms201 Abnormal Level Earthquake (ALE): Intense earthquake of abnormal severity under the action of whichthe structure should not suffer complete loss of integrity. When exposed to the ALE, a manned structure issupposed to maintain structural and/or floating integrity for a sufficient period of time to enable evacuation totake place.202 Accidental Limit States (ALS): Limit state related to the possibility of the structure to resist accidentalloads and maintain integrity and performance of the structure due to local damage or flooding.203 Accidental loads (A): Rare occurrences of extreme environmental loads, fire, flooding, explosions,dropped objects, collisions, unintended pressure differences, leakage of LNG etc.204 Aggregates: Constituent material of concrete or grout added to

dnv-os-c502: offshore concrete structures · det norske veritas as offshore standard dnv-os-c502,...

Documents