DNVGL-RU-SHIP-Pt6Ch1 Structural strength and integrity...P a r t 6 C h a p t e r 1 C h a n g e s-c u r r e n t Rules for classification: Ships — DNVGL-RU-SHIP-Pt6Ch1. Edition October

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DNV GL AS

RULES FOR CLASSIFICATION

ShipsEdition October 2015

Part 6 Additional class notations

Chapter 1 Structural strength and integrity

FOREWORD

DNV GL rules for classification contain procedural and technical requirements related to obtainingand retaining a class certificate. The rules represent all requirements adopted by the Society asbasis for classification.

© DNV GL AS October 2015

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

If any person suffers loss or damage which is proved to have been caused by any negligent act or omission of DNV GL, then DNV GL shallpay compensation to such person for his proved direct loss or damage. However, the compensation shall not exceed an amount equal to tentimes the fee charged for the service in question, provided that the maximum compensation shall never exceed USD 2 million.

In this provision "DNV GL" shall mean DNV GL AS, its direct and indirect owners as well as all its affiliates, subsidiaries, directors, officers,employees, agents and any other acting on behalf of DNV GL.

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Rules for classification: Ships — DNVGL-RU-SHIP-Pt6Ch1. Edition October 2015 Page 3Structural strength and integrity

DNV GL AS

CHANGES – CURRENT

This is a new document.

The rules enter into force 1 January 2016.

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CONTENTS

Changes – current...................................................................................................... 3

Section 1 Strengthened for grab loading and unloading - Grab................................ 101 General................................................................................................. 10

1.1 Introduction.......................................................................................101.2 Scope............................................................................................... 101.3 Application.........................................................................................101.4 Class notations.................................................................................. 101.5 Definitions......................................................................................... 11

2 Documentation......................................................................................112.1 Documentation requirements............................................................... 11

3 Design requirements.............................................................................113.1 Plating.............................................................................................. 11

Section 2 Strengthened for heavy cargo - Strengthened.......................................... 131 General................................................................................................. 13



3 Design requirements - strengthened (HA)............................................143.1 External pressure due to heavy distributed load..................................... 143.2 Hull local scantlings............................................................................14

4 Design requirements - strengthened (DK)............................................144.1 External pressure due to heavy distributed load..................................... 144.2 Hull local scantlings............................................................................15

5 Design requirements - strengthened (IB).............................................155.1 Structural arrangement - double bottom structure.................................. 155.2 Internal pressure due to heavy distributed load......................................155.3 Hull local scantlings............................................................................155.4 Loading instrument.............................................................................16

Section 3 Strengthened for heavy liquid - HL...........................................................17

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1 General................................................................................................. 171.1 Introduction.......................................................................................171.2 Scope............................................................................................... 171.3 Application.........................................................................................171.4 Class notations.................................................................................. 171.5 Definitions......................................................................................... 18


3 Design requirements.............................................................................183.1 Loads................................................................................................183.2 Hull scantlings................................................................................... 18

Section 4 Strengthened for heavy cargo in bulk - HC...............................................191 General................................................................................................. 19



3 Pressures and forces due to dry bulk cargo..........................................243.1 General............................................................................................. 243.2 Mass and density............................................................................... 24

4 Loading conditions................................................................................264.1 Specific design loading conditions.........................................................264.2 Design load combinations for direct strength analysis..............................274.3 Standard loading conditions for fatigue assessment................................ 50

5 Hold mass curves................................................................................. 525.1 Introduction.......................................................................................525.2 Single cargo hold............................................................................... 535.3 Two adjacent holds.............................................................................67

6 Hull local scantling............................................................................... 776.1 Plating.............................................................................................. 776.2 Stiffeners...........................................................................................776.3 Intersection of stiffeners and primary supporting members...................... 77

7 Finite element analysis.........................................................................787.1 Cargo hold analysis............................................................................ 787.2 Local structural strength analysis......................................................... 78

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8 Buckling................................................................................................788.1 Hull girder buckling............................................................................ 78

9 Fatigue..................................................................................................789.1 Fatigue strength calculations................................................................789.2 Prescriptive fatigue strength assessment............................................... 799.3 Finite element stress analysis.............................................................. 80

10 Loading manual and loading instrument.............................................8010.1 Loading manual................................................................................8010.2 Loading instrument........................................................................... 8110.3 Guidance for loading/unloading sequences........................................... 81

Section 5 Strengthened for ore cargo - OC.............................................................. 841 General................................................................................................. 84



3 Pressures and forces due to dry bulk cargo..........................................873.1 General............................................................................................. 873.2 Mass and density............................................................................... 87

4 Loading conditions................................................................................884.1 Specific design loading conditions.........................................................884.2 Design load combinations for direct strength analysis..............................894.3 Standard loading conditions for fatigue assessment...............................113

5 Hold mass curves............................................................................... 1155.1 Introduction..................................................................................... 1155.2 Single cargo hold............................................................................. 1165.3 Two adjacent holds........................................................................... 120

6 Hull local scantling............................................................................. 1216.1 Plating.............................................................................................1216.2 Stiffeners.........................................................................................1216.3 Intersection of stiffeners and primary supporting members.................... 121

7 Finite element analysis.......................................................................1217.1 Cargo hold analysis.......................................................................... 1227.2 Local structural strength analysis........................................................123

8 Buckling.............................................................................................. 124

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8.1 Hull girder buckling...........................................................................1249 Fatigue................................................................................................124

9.1 Fatigue strength calculations..............................................................1249.2 Prescriptive fatigue strength assessment............................................. 1249.3 Finite element stress analysis............................................................ 125

10 Loading manual and loading instrument...........................................12510.1 Loading manual.............................................................................. 12510.2 Loading instrument......................................................................... 12510.3 Guidance for loading/unloading sequences......................................... 125

Section 6 Extended fatigue analysis of ship details - Plus...................................... 1261 General............................................................................................... 126

1.1 Introduction..................................................................................... 1261.2 Scope..............................................................................................1261.3 Application.......................................................................................1261.4 Class notations.................................................................................1261.5 Definitions....................................................................................... 127

2 Documentation....................................................................................1272.1 Documentation requirements............................................................. 127

3 Design requirements...........................................................................1283.1 General........................................................................................... 1283.2 Finite element analysis......................................................................1283.3 Fatigue critical details....................................................................... 1293.4 Fatigue strength assessment..............................................................131

Section 7 Direct analysis of ship structures - CSA..................................................1321 General............................................................................................... 132



3 Design requirements...........................................................................1343.1 General........................................................................................... 1343.2 Loading conditions............................................................................ 1353.3 Wave load analysis........................................................................... 1353.4 Finite element analysis......................................................................137

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3.5 Fatigue critical details....................................................................... 1383.6 Fatigue strength assessment..............................................................1413.7 Yield and buckling capacity................................................................1413.8 Hull girder ultimate strength.............................................................. 142

Section 8 Global Strength Analysis of Container Ships - RSD................................. 1451 General............................................................................................... 145



3 Design requirements...........................................................................1473.1 General........................................................................................... 1473.2 Loading conditions............................................................................ 1473.3 Wave load analysis........................................................................... 1473.4 Finite element analysis......................................................................1483.5 Fatigue critical details....................................................................... 1493.6 Fatigue strength assessment..............................................................1493.7 Yield and buckling capacity................................................................1503.8 Hatch cover movements.................................................................... 150

Section 9 Performance standard for protective coatings - COAT-PSPC....................1511 General............................................................................................... 151

1.1 Introduction..................................................................................... 1511.2 Scope..............................................................................................1511.3 Application.......................................................................................1511.4 Class notations.................................................................................1521.5 References.......................................................................................152


3 Design requirements...........................................................................1543.1 Corrosion prevention systems............................................................ 1543.2 Coating Technical File (CTF)...............................................................1543.3 Yard coating inspectors..................................................................... 1553.4 Review of coating technical file.......................................................... 155

Section 10 Strengthening against collisions - COLL................................................157

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1 General............................................................................................... 1571.1 Introduction..................................................................................... 1571.2 Scope..............................................................................................1571.3 Application.......................................................................................1571.4 Class notations.................................................................................1571.5 Definitions....................................................................................... 157


3 Design requirements...........................................................................1583.1 General........................................................................................... 1583.2 Deformation energy.......................................................................... 1593.3 Critical speed................................................................................... 162

Section 11 Wave induced hull girder vibrations - WIW.......................................... 1641 General............................................................................................... 164

1.1 Introduction..................................................................................... 1641.2 Scope..............................................................................................1641.3 Application.......................................................................................1641.4 Class notation.................................................................................. 1641.5 Definitions....................................................................................... 164


3 Design requirements...........................................................................1653.1 General........................................................................................... 1653.2 Loading conditions............................................................................ 1663.3 Sea states....................................................................................... 1663.4 Speed............................................................................................. 1663.5 Damping..........................................................................................1663.6 Extreme loads.................................................................................. 1663.7 Target fatigue life............................................................................. 1673.8 Extreme strength calculations............................................................ 1673.9 Fatigue strength calculations..............................................................167

4 Ship type requirements...................................................................... 1674.1 Container ships................................................................................ 1674.2 Other ships......................................................................................168

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SECTION 1 STRENGTHENED FOR GRAB LOADING AND UNLOADING -GRAB

1 General

1.1 IntroductionAdditional class notation Grab includes design requirements for local strengthening of structural membersthat are exposed to impact loads by grabs, when loading and unloading.

1.2 ScopeThe scope of additional class notation Grab is to add an additional level of safety in relation to thestrengthening of those parts of the hull structure that are exposed to impact loads from grabs. The rules inthis section are considered to satisfy the requirements for determining the net thickness [strengthening] ofstructural elements, such as inner bottom and lower parts of transverse and longitudinal bulkheads; alignedwith, and dependent upon, selected qualifiers as shown in Table 1.

1.3 ApplicationShips built in compliance with the design requirements given in this section may be assigned the additionalclass notation Grab with qualifiers giving further description of the area(s) being strengthened and includingthe weight of grab. The additional class notation Grab does not negate the use of heavier grabs. However,the owner and operators should be made aware of the increased risk of local damage and possible earlyrenewal if heavier grabs are used to load or unload cargo.

1.4 Class notations1.4.1 GrabShips built in compliance with the requirements as specified in Table 1 will be assigned the additional notationrelated to structural strength and integrity as follows:

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Table 1 Additional class notation - Grab

Class Notation Qualifier Purpose Application

1-XStrengthened inner bottom forgrab loading and unloading, withgrab mass X ≥ 20 t

Mandatory for ships with Class Notation HC(M),unless Grab(2-X) or Grab(3-X) is assigned

Mandatory for ships with freeboard length LLL

≥ 150 m, carrying solid bulk cargoes havinga density ≥ 1.0 t/m3, unless Grab(2-X) orGrab(3-X) is assigned

2-X

Strengthened inner bottom andlower part of transverse bulkheadfor grab loading and unloading,with grab mass X ≥ 20 t

Grab

Mandatory:

Yes

Design requirements:

[3]

FiS requirements:

NA3-X

Strengthened inner bottom, andlower part of transverse bulkheadand longitudinal bulkhead for grabloading and unloading, with grabmass X ≥ 20 t

Mandatory for Ore carrier with Class NotationOC(M) or OC(H)

Mandatory for dry cargo ships with ClassNotation HC(A), HC(B) or HC(B*)

1.5 Definitions1.5.1 SymbolsFor symbols not defined in this section, refer to Pt.3 Ch.1 Sec.4 [2].

MGR = mass of unladen grab, in t, taken not less than:= 35 t for ships with L ≥ 250 m,= 30 t for ships with 200 m ≤ L < 250 m,= 20 t otherwise.

2 Documentation

2.1 Documentation requirements2.1.1 GrabAll documentation requirements are covered by main class.

3 Design requirements

3.1 Plating3.1.1 GeneralThe net thickness of plating strengthened for grab loading and unloading shall be taken as the greater of thefollowing values:

— t, as obtained according to requirements in Pt.3 Ch.6 and Pt.5 Ch.1— tG, as defined in [3.1.2] and [3.1.3] for the structural elements listed in Table 2.

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Table 2 Structural elements subject to strengthening depending on qualifiers of the Grab notation

Structural elements Grab(1-X) Grab(2-X) Grab(3-X)

Inner bottom, excluding bilge wells V V V

Lower part of transverse bulkhead, including the followingstructural elements, where applicable:

— Transverse lower stool plating— Transverse plane bulkhead plating— Face plate of transverse corrugated bulkheads without

lower stool

- V V

Lower part of longitudinal bulkhead, including the followingstructural elements, where applicable:

— Hopper tank sloped plating— Vertical inner hull

- - V

V: To be strengthened -: Need not be strengthened

3.1.2 Inner bottom platingThe net thickness tG, in mm, of the inner bottom plating shall be obtained from the following formula:

3.1.3 Vertical and sloped cargo hold boundariesThe net thickness tG, in mm, of vertical and sloped cargo hold boundaries up to a height of 3.0 m above thelowest point of the inner bottom shall be obtained from the following formula:

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SECTION 2 STRENGTHENED FOR HEAVY CARGO - STRENGTHENED

1 General

1.1 IntroductionThe additional class notation Strengthened includes an increased level of safety, related to thestrengthening of those parts of the hull structure that are exposed to heavy cargo loading.

1.2 ScopeThe scope of the rules in this section is considered to satisfy the requirements for strengthening of structuralelements, such as weather deck hatch covers, weather decks and inner bottoms, within specified design loadcriteria, for ships loaded with heavy cargo. Design requirements related to external pressure, due to heavydistributed loads, are applied through ensuring compliance with DNV GL rules.

1.3 ApplicationShips built in accordance with the design requirements given in this section may be assigned the additionalnotation Strengthened with qualifiers giving further description of the area(s) being strengthened.

1.4 Class notations1.4.1 StrengthenedShips built in compliance with the requirements as specified in Table 1 may be assigned the additional classnotation Strengthened related to structural strength and integrity as follows:

Table 1 Additional class notation - Strengthened


HA Weather deck hatch coversstrengthened for heavy cargo

DK Weather deck strengthenedfor heavy cargo

Strengthened

Mandatory:

No


[3] to [5]

FiS requirements:

NA

IB Inner bottom strengthenedfor heavy cargo


Pdl-s = static pressure, in kN/m2, due to distributed load on inner bottom and weather deckPdl = total pressure, in kN/m2, due to distributed load on inner bottom and weather deck

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PC = static pressure, in kN/m2, due to distributed load on weather deck hatch coversP = total pressure, in kN/m2, due to distributed load on weather deck hatch covers.

2 Documentation

2.1 Documentation requirements2.1.1 StrengthenedAll documentation requirements are covered by main class.

3 Design requirements - strengthened (HA)

3.1 External pressure due to heavy distributed load3.1.1 GeneralThe total pressure due to distributed load, P, in kN/m2, shall be in accordance with Pt.3 Ch.12 Sec.4 [2.3.1]or CSR Pt.2 Ch.1 Sec.5 [4.1.4], applying a static distributed load in accordance with [3.1.2].

3.1.2 Static distributed loadThe static pressure due to distributed load, PC, in kN/m2, shall be specified, without being less than thevertical weather design load PH, in kN/m2, given in Pt.3 Ch.12 Sec.4 Table 3.

Guidance note:The static distributed load, PC, in t/m2, will be given in the appendix to the classification certificate.

---e-n-d---of---g-u-i-d-a-n-c-e---n-o-t-e---

3.2 Hull local scantlings3.2.1 GeneralThe requirements given in Pt.3 Ch.12 Sec.4 or CSR Pt.2 Ch.1 Sec.5 [5] shall be complied with, applyingpressure in accordance with [3.1].

4 Design requirements - strengthened (DK)

4.1 External pressure due to heavy distributed load4.1.1 GeneralThe total pressure due to distributed load, Pdl, in kN/m2, shall be in accordance with Pt.3 Ch.4 Sec.5 [2.3.1]or CSR Pt.1 Ch.4 Sec.5 [2.3.1], applying a static distributed load in accordance with [4.1.2].

4.1.2 Static distributed loadThe static pressure due to distributed load, Pdl-s, in kN/m2, shall be specified, without being less than theminimum wave pressure on exposed deck PD-min, in kN/m2, given in Pt.3 Ch.4 Sec.5 Table 30.

Guidance note:The static distributed load, Pdl-s, in t/m2, will be given in the appendix to the classification certificate.


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4.2 Hull local scantlings4.2.1 GeneralThe requirements given in Pt.3 Ch.6 Sec.1 to Sec.7 or CSR Pt.1 Ch.6 Sec.1 to Sec.5 and CSR Pt.1 Ch.3 Sec.6[5] shall be complied with, applying pressure in accordance with [4.1].

5 Design requirements - strengthened (IB)

5.1 Structural arrangement - double bottom structure5.1.1 Double bottom with longitudinal stiffeningFor a longitudinally stiffened double bottom the spacing of floors shall not be greater than the height of thedouble bottom.

5.1.2 Double bottom with transverse stiffeningFor transversely stiffened double bottom floors shall be fitted at every frame.

5.2 Internal pressure due to heavy distributed load5.2.1 GeneralThe total pressure due to distributed load, Pdl, in kN/m2, shall be in accordance with Pt.3 Ch.4 Sec.6 [2.2.1],applying a static distributed load in accordance with [5.2.2].

5.2.2 Static distributed loadThe static pressure due to distributed load, Pdl-s, in kN/m2, shall be specified.

For ships carrying dry cargo in bulk the static pressure due to distributed load, Pdl-s, in kN/m2, shall not beless than:

where:

ρC = cargo mass density in homogeneous loading condition for fully filled hold, in t/m3, in accordancewith Pt.5 Ch.1 Sec.2 Table 2

hc = height of bulk cargo for fully filled hold, in m, from the inner bottom to the upper surface of bulkcargo, as defined in Pt.5 Ch.1 Sec.2 [3.3.1].

Guidance note:The static distributed load, Pdl-s, in t/m2, will be given in the appendix to the classification certificate.


5.3 Hull local scantlings5.3.1 GeneralThe requirements given in Pt.3 Ch.6 Sec.1 to Sec.5 and Sec.7 shall be complied with, applying pressure inaccordance with [5.2].

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5.3.2 Primary supporting membersThe scantlings of primary supporting members within the double bottom shall be determined by an advancedcalculation method in accordance with Pt.3 Ch.6 Sec.6 [2.2].Unless block loading conditions with static distributed load in accordance with [5.2.2] are included inthe loading manual, the scantlings of primary supporting members within the double bottom shall bestrengthened for internal pressures in accordance with [5.2] on the minimum ballast draught, TBAL.

Guidance note:If block loading conditions are included in the loading manual, the design load combinations for direct strength analysis of PSM givenin Pt.5 Ch.1 Sec.5 [4.2.5] may be used as guidance.


5.4 Loading instrumentShips having large deck openings shall belong to category I irrespectively of ship’s length and shall beprovided with a loading instrument complying with the requirements given in Pt.3 Ch.1 Sec.5 [3].

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SECTION 3 STRENGTHENED FOR HEAVY LIQUID - HL

1 General

1.1 IntroductionThe additional class notation HL sets requirements for the strengthening of cargo tanks or holds, which carryliquids that are more dense than sea water.

1.2 ScopeThe scope of the additional class notation HL is to satisfy the requirements for the strengthening of structuralmembers of cargo tanks or holds that are exposed to heavy liquid loads. The design criteria includes strengthassessment, related to static and dynamic liquid pressure, the application of design pressure loads for hullscantlings, and fatigue strength assessment related to given maximum design densities, primarily for shipsintended for the carriage of heavy liquids.

1.3 ApplicationThe additional class notation HL applies to ships carrying heavy liquids in cargo tanks or holds [98% full],where the density of the liquid is greater than that of sea water. Ships built in accordance with the designrequirements given in this section may be assigned the additional notation HL with qualifier ρ giving furtherdescription of the maximum design density, in t/m3, in specified cargo tanks or holds.

1.4 Class notations1.4.1 HLShips built in compliance with the requirements as specified in Table 1 may be assigned the additionalnotation HL, related to structural strength and integrity of cargo tanks or holds, as follows:

Table 1 Additional class notation - HL


HL

Mandatory:

No


[3]

FiS requirements:

NA

ρCargo tanks or holds strengthened for heavyliquid, where ρ denotes the maximum density int/m3 in specified cargo tanks or holds

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ρL = density of liquid in the tank, in t/m3.

2 Documentation

2.1 Documentation requirements2.1.1 HLAll documentation requirements are covered by main class.


3.1 Loads3.1.1 Internal loads for strength assessmentFor strength assessment, the static liquid pressure and dynamic liquid pressure shall be in accordance withPt.3 Ch.4 Sec.6 or IACS common structural rules Pt.1 Ch.4 Sec.6, applying the given design density.

Guidance note:The design density, ρL, in t/m3, will be given in the appendix to the classification certificate.


3.2 Hull scantlings3.2.1 GeneralThe requirements given in Pt.3 and, where applicable, in Pt.5, or IACS common structural rules shall becomplied with when applying design pressure loads, in accordance with [3.1].

3.2.2 Fatigue strength assessmentFor ships primarily intended for carriage of heavy liquids, fatigue strength assessment shall be carried out,applying the given design density requirements.

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SECTION 4 STRENGTHENED FOR HEAVY CARGO IN BULK - HC

1 General

1.1 IntroductionAdditional class notation HC includes design requirements for cargo ships intended for the carriage of drybulk cargoes. Strengthening of these types of ship will be determined by conditions related to the intendedtrading pattern and types of dry bulk cargo carried.

1.2 ScopeThe scope of additional class notation HC is to add a further level of safety in relation to the strengthening ofthe hull structure, due to the carriage of dry bulk cargo. The rules in this section are considered to satisfy thedesign requirements based on the given rule defined maximum dry bulk cargo density and the rule definedloading flexibility, depending upon selected qualifiers, which are shown in Table 1.This section includes requirements for hull strength, including:

— [3]: Pressures and forces due to dry bulk cargo— [4]: Loading conditions— [3]: Hold mass curves— [6]: Hull local scantling— [7]: Finite element analysis— [8]: Buckling— [9]: Fatigue— [10]: Loading manual and loading instrument.

1.3 ApplicationOne of the HC notations specified in this section shall be applied to:

— ships assigned the ship type notation General dry cargo ship designed for carriage of solid bulk cargoes,having minimum five cargo holds and a length L of not less than 150 m

— ships assigned the ship type notation Multi-purpose dry cargo ship designed for carriage of solid bulkcargoes, having minimum five cargo holds and a length L of not less than 150 m

— ships assigned the ship type notation Bulk carrier (without CSR) having a length L of not less than 150m.

One of the HC notations may be assigned to ships designed for the carriage of solid bulk cargoes with lessthan five cargo holds and/or length L of less than 150 m.

1.4 Class notations1.4.1 HCShips built in compliance with the requirements as specified in Table 1 will be assigned the additional notationrelated to structural strength and integrity as follows:

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Table 1 Additional class notation - HC


A

Strengthened to carry drybulk cargoes of density ≥1.0 t/m3 with specified holdsempty at scantling draught, inaddition to HC(B)

B

Strengthened to carry drybulk cargoes of density ≥ 1.0t/m3 with all holds loaded, inaddition to HC(C)

B*

Strengthened to carry drybulk cargoes of density ≥ 1.0t/m3 with any hold empty atscantling draught

CStrengthened to carry drybulk cargoes of density < 1.0t/m3

HC

Mandatory:

Yes


[3] to [10]

FiS requirements:

NA

MDesigned to carry dry bulkcargoes as described in theloading manual

HC with one of qualifiers A, B, B*, C or M aremandatory for:

— General dry cargo ship designed forcarriage of solid bulk cargoes, with L ≥ 150m, having minimum five cargo holds

— Multi-purpose dry cargo ship designed forcarriage of solid bulk cargoes, with L ≥ 150m, having minimum five cargo holds

— Bulk carrier without CSR notation, with L ≥150 m

1.4.2 Maximum cargo densityShips built in compliance with the requirements as specified in Table 2 will be assigned the additional notationrelated to structural strength and integrity as follows:

Table 2 Additional class notation - Maximum cargo density


Maximum cargo density

Mandatory:

Yes


[4.1.3] to [4.1.4]

FiS requirements:

NA

ρ Designed for a maximumcargo density ρ in t/m3

Mandatory for ships with Class Notation HC(A),HC(B) or HC(B*) designed for a maximumcargo density < 3.0 t/m3

1.4.3 No MPShips built in compliance with the requirements as specified in Table 3 will be assigned the additional notationrelated to structural strength and integrity as follows:

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Table 3 Additional class notation - No MP


No MP

Mandatory:

No


[4] to [9]

FiS requirements:

NA

<None>Ships not designed for loadingand unloading in multipleports

1.4.4 Holds n may be emptyShips built in compliance with the requirements as specified in Table 4 will be assigned the additional notationrelated to structural strength and integrity as follows:

Table 4 Additional class notation - Holds n may be empty


Holds n may be empty

Mandatory:

Yes


[4.1.4]

FiS requirements:

NA

<None>

Holds may be empty atscantling draught where n isthe identification number foreach hold that may be empty

Mandatory for ships with class notationHC(A),and HC(M) if alternate loadingconditions are included in the loading manual


h = vertical distance from the top of inner bottom plating to the lowest point of the upper deckplating at the ship’s centreline, in m

ha = vertical distance from the top of inner bottom plating to the lowest point of the upper deckplating at the ship’s centreline of the aft cargo hold of two adjacent cargo holds, in m

hf = vertical distance from the top of inner bottom plating to the lowest point of the upper deckplating at the ship’s centreline of the fore cargo hold of two adjacent cargo holds, in m

MH = cargo mass, in t, as defined in Pt.5 Ch.1 Sec.2MFull = cargo mass, in t, as defined in Pt.5 Ch.1 Sec.2MHD = cargo mass, in t, as defined in Pt.5 Ch.1 Sec.2MBLK = the maximum cargo mass in each cargo hold of two adjacent cargo holds according to the block

loading condition in the loading manual, in t

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VH = volume in m3, as defined in Pt.5 Ch.1 Sec.2Va = volume of the after cargo hold of two adjacent cargo holds excluding volume of the hatchway

part, in m3

Vf = volume of the forward cargo hold of two adjacent cargo holds excluding volume of the hatchwaypart, in m3

Σ = the sum of masses of two adjacent cargo holdsEA = empty hold in alternate loading conditionFA = full hold in alternate loading conditionT = draught, horizontal axis for the hold mass curves, in m, at mid-hold position of single cargo hold

length or at mid-length of the two adjacent cargo holds consideredTHB = deepest ballast draught, in m, at mid-hold position of single cargo hold length or at mid-length

of the two adjacent cargo holds consideredTLB = lightest ballast draught, in m, at mid-hold position of single cargo hold length or at mid-length of

the two adjacent cargo holds consideredTmin = 0.75 TSC or THB, whichever is greater, in mTH1 = minimum permissible mean draught in way of two adjacent cargo holds, in m, in harbour

condition, with each of the two adjacent cargo holds having maximum allowable cargo weight, tobe taken as:

— for HC(A), HC(B) and HC(C) ships having No MP notation assigned, with MFull:

— for HC(A), HC(B) and HC(C) ships not having No MP notation assigned, with MFull:

— for HC(B*) ships, with 1.1MFull:

TH2 = minimum permissible draught at mid-hold position, in m, in harbour condition, in way of a single

cargo hold with MFull, to be taken as:

— for EA holds of HC(A) ships or HC(B) and HC(C) ships having No MP notation assigned:

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— for EA holds of HC(A) ships or HC(B) and HC(C) ships not having No MP notation assigned:

TH3 = minimum permissible mean draught in way of two adjacent cargo holds, in m, in harbour

condition in case of block loading with MBLK in each of the two adjacent holds of HC(A) ships, tobe taken as:

TH4 = minimum permissible draught at mid-hold position, in m, in harbour condition, in way of a single

cargo hold having maximum allowable ore cargo weight, to be taken as:

— for FA holds of HC(A) ships, with MHD:

— for and hold of HC(B*) ships, with 1.2MFull:

2 Documentation

2.1 Documentation requirements2.1.1 HCDocumentation shall be submitted as required by Table 5.

Table 5 Documentation requirements - HC

Object Documentation type Additional description Info

H112 – Loading sequence description,preliminary AP, VS

Ship hull structure

H114 – Loading sequence description, final AP, VS

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AP = For approval; FI = For information; ACO = As carried out; L = Local handling; R = On request; TA = Covered bytype approval; VS = Vessel specific

For general requirements for documentation, including definition of the info codes, see Pt.1 Ch.3 Sec.1.For a full definition of the documentation types, see Pt.1 Ch.3 Sec.3.

3 Pressures and forces due to dry bulk cargo

3.1 GeneralPressures and forces due to dry bulk cargo shall be in accordance with Pt.5 Ch.1 Sec.2 [3], applying cargothe mass and density given in [3.2].

3.2 Mass and density— for strength assessment: the values are defined in Table 6— for fatigue assessment: the values are defined in Table 7.

Table 6 Dry bulk cargo mass and density for strength assessment

Homogeneous loading condition Alternate loading condition

HCCargo mass

Cargo density Fully filled hold Partiallyfilled hold Fully filled hold Partially filled hold

M M = MFull

HC(C)ρC

but not less than 1.0

N/A N/A

M M = MFull M = MH

HC(B)ρC


ρC = 3.0 1)N/A

HC(A) M M = MFull M = MH

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Homogeneous loading condition Alternate loading condition

HCCargo mass

Cargo density Fully filled hold Partiallyfilled hold Fully filled hold Partially filled hold

ρC


ρC = 3.0 1)

ρC = 3.0 1)

M M = MFull M = MH M =1.2 MFull M =1.2 MFull

HC(B*)ρC


ρC = 3.0 1)

ρC = 3.0 1)

M M = MH M = MH M = MHD M = MHD

HC(M)2), 3)

ρC

but not less than 0.7 4)

Maximum valuespecified in theloading manual

Maximum valuespecified in theloading manual

1) To be taken as 3.0 unless an alternative maximum allowable cargo density is specified in the loading manual.In such cases, the maximum density of the cargo that the ship is allowed to carry shall be indicated within theadditional notation Maximum cargo density (x.y t/m3) as defined in [1.4.2].

2) Alternate loading conditions are only applicable if such conditions are included in the loading manual.3) Homogeneous loading condition with partially filled hold is only applicable if loading conditions having a mass

density not less than 1.0 are included in the loading manual.4) If a mass density of 0.7 for all cargo holds represents a total cargo intake Σ 0.7MFullthat is exceeding the total cargo

capacity of the ship ρC may be reduced after special consideration.

Table 7 Dry bulk cargo mass and density for fatigue assessment

HC Cargo massCargo density

Homogeneous loading condition,fully filled hold

Alternate loading condition,partially filled hold

M M = MH

HC(C)ρC

HC(B) M M = MH

N/A

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HC Cargo massCargo density

Homogeneous loading condition,fully filled hold

Alternate loading condition,partially filled hold

ρC

M M = MH M = MHD

HC(A)ρC

ρC = 3.0 1)

M M = MH M = 1.2MFull

HC(B*)ρC

ρC = 3.0 1)

M M = MH M = MHD

HC(M)2)

ρC

Maximum value specifiedin the loading manual

1) To be taken as 3.0 unless an alternative maximum allowable cargo density is specified in the loading manual.In such cases, the maximum density of the cargo that the ship is allowed to carry shall be indicated within theadditional notation Maximum cargo density (x.y t/m3) as defined in [1.4.2].

2) Alternate loading conditions are only applicable if such conditions are included in the loading manual.

4 Loading conditions

4.1 Specific design loading conditions4.1.1 GeneralThe seagoing loading conditions given in [4.1.2] to [4.1.6] shall be included, as a minimum, in the loadingmanual.

4.1.2 Cargo loading condition for HC(C) and HC(M)Homogeneous cargo loaded condition shall be included in the loading manual where the cargo densitycorresponds to all cargo holds, including hatchways, being 100% full at scantling draught with all ballasttanks empty.

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4.1.3 Cargo loading condition for HC(B)As required for HC(C), plus:Homogeneous cargo loaded condition shall be included in the loading manual where the cargo density istaken equal to 3.0 t/m3, and all cargo holds are taken with the same filling ratio (cargo mass/hold cubiccapacity) at scantling draught with all ballast tanks empty.In cases where the cargo density applied for this design loading condition is different from 3.0 t/m3, themaximum density of the cargo that the ship is allowed to carry shall be indicated with the additional notationMaximum cargo density (x.y t/m3).

4.1.4 Cargo loading condition for HC(A)As required for HC(B), plus:At least one cargo loaded condition with specified holds empty, with cargo density 3.0 t/m3, and the samefilling ratio (cargo mass/hold cubic capacity) in all loaded cargo holds at scantling draught with all ballasttanks empty.The combination of specified empty holds shall be indicated with the additional notation Holds a, b, … maybe empty.In such cases where the design cargo density applied is different from 3.0 t/m3, the maximum density ofthe cargo that the ship is allowed to carry shall be indicated with the additional notation Maximum cargodensity (x.y t/m3).

4.1.5 Cargo loading condition for HC(B*)As required for HC(B), plus:Cargo loaded conditions showing holds empty at scantling draught with all ballast tanks empty. Each holdshall be shown empty at scantling draught in minimum one seagoing loading condition.

4.1.6 Ballast loading conditionsAs required in Pt.3 Ch.4 Sec.8 [1.1], plus:

1) the ballast tanks may be full, partially full or empty. Where partially full option is used, the requirementsin Pt.3 Ch.4 Sec.8 [1.2.1] shall be complied with

2) any cargo hold or holds adapted for the carriage of water ballast at sea shall be empty3) the propeller shall be fully immersed4) the trim shall be by the stern and shall not exceed 0.015L5) the forward bottom structures shall be strengthened in accordance with Pt.3 Ch.10 Sec.2 against

slamming for the condition listed above at the lightest forward draught TF.

4.1.7 Steel coils or heavy cargoesIn case of steel coil loading or heavy cargoes the hold mass curves given in [5] are not valid. The followingnote shall be included in the loading manual:“Where the ship engages in a service carrying such cargoes as steel coils or heavy cargoes that may have anadverse effect on the local strength of the double bottom and which is not described as cargo in the loadingmanual, the maximum permissible and the minimum required mass of cargo shall be considered specially.”

4.2 Design load combinations for direct strength analysis4.2.1 Applicable general loading patternsThe following loading patterns shall be applied:

a) any cargo hold carrying MFull, with fuel oil tanks in way of the cargo hold, if any, being 100% full andballast water tanks in the double bottom in way of the cargo hold being empty, at scantling draught TSC

b) any cargo hold carrying minimum 50% of MH, with all double bottom tanks in way of the cargo holdbeing empty, at scantling draught TSC

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c) any cargo hold taken empty, with all double bottom tanks in way of the cargo hold being empty, at thedeepest ballast draught THB.

For HC(M) item a): MH instead of MFull is applicable.

4.2.2 Multiport conditionsThe following multiport conditions are applicable to HC(C), HC(B) and HC(A), except when the additionalnotation No MP is assigned:

a) any cargo hold carrying MFull, with fuel oil tanks in way of the cargo hold, if any, being 100% full andballast water tanks in the double bottom in way of the cargo hold being empty, at 67% of scantlingdraught

b) any cargo hold taken empty, with all double bottom tanks in way of the cargo hold being empty, at 83%of scantling draught

c) any two adjacent cargo holds carrying MFull, with the next holds being empty, with fuel oil tanks in way ofthe cargo holds, if any, being 100% full and ballast water tanks in the double bottom in way of the cargoholds being empty, at 67% of the scantling draught. This requirement to the mass of the cargo and fueloil in double bottom tanks in way of the cargo hold applies also to the condition where the adjacent holdis filled with ballast

d) any two adjacent cargo holds being empty, with the next holds being full, with all double bottom tanks inway of the cargo hold being empty, at 75% of scantling draught.

4.2.3 Alternate conditionsThe following alternate conditions are applicable to HC(A) only:

a) cargo holds which are intended to be empty at scantling draught, being empty with all double bottomtanks in way of the cargo holds also being empty

b) cargo holds which are intended to be loaded with high density cargo, carrying MHD plus 10% of MH, inthe partially filled condition with highest density according to Table 6. The fuel oil tanks in way of thecargo hold, if any, being 100% full and ballast water tanks in the double bottom being empty in way ofthe cargo hold, at scantling draught

c) cargo holds which are intended to be loaded with high density cargo, carrying MHD plus 10% of MH in thefull condition with lowest density according to Table 6. The fuel oil tanks in way of the cargo hold, if any,being 100% full and ballast water tanks in the double bottom being empty in way of the cargo hold, atscantling draught

d) if the ship is intended to operate in alternate block load condition, any two adjacent cargo holds shall beloaded with the next holds being empty, carrying 10% of MH in each hold in addition to the maximumcargo load according to that design loading condition, with fuel oil tanks in way of the cargo hold, if any,being 100% full and ballast water tanks in the double bottom in way of the cargo hold being empty, atscantling draught. In operation the maximum allowable mass shall be limited to the maximum cargo loadaccording to the design loading conditions.

For HC(M) having alternate loading condition included in the loading manual: item a) is applicable, items b)and c) with MHD instead of MHD plus 10% of MH, and item d) is not applicable.

4.2.4 Heavy ballast conditionThe following condition applies to ballast holds only, if applicable:

— cargo holds which are designed as ballast water holds, being 100% full of ballast water includinghatchways, with all double bottom tanks in way of the cargo hold being 100% full, at any heavy ballastdraught. For ballast holds adjacent to topside wing, hopper and double bottom tanks, it shall be froma strength perspective, acceptable that the ballast holds are filled when the topside wing, hopper anddouble bottom tanks are empty.

4.2.5 Multiport conditions ensuring high loading flexibilityThe following conditions are applicable to HC(B*) only:

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a) any cargo hold carrying 1.2MFULL, with fuel oil tanks in way of the cargo hold, if any, being 100% fulland ballast water tanks in the double bottom in way of the cargo hold being empty, at 67% of scantlingdraught

b) any cargo hold taken empty, with all double bottom tanks in way of the cargo hold being empty, atscantling draught

c) any two adjacent cargo holds carrying 1.1MFULL, with the next holds being empty, with fuel oil tanks inway of the cargo holds, if any, being 100% full and ballast water tanks in the double bottom in way ofthe cargo holds being empty, at 67% of the scantling draught. This requirement related to the massof the cargo and fuel oil in double bottom tanks in way of the cargo holds applies also to the conditionwhere the adjacent hold is filled with ballast

d) any two adjacent cargo holds being empty, with the next holds being full, with all double bottom tanks inway of the cargo hold being empty, at 75% of scantling draught

e) any cargo hold loaded with high density cargo in the partially filled condition with highest densityaccording to Table 6

f) any cargo hold loaded with low density cargo in the full condition with lowest density according to Table6.

4.2.6 Additional harbour conditionThe following additional harbour conditions shall be applied:

a) at reduced draught during loading and unloading in harbour, the maximum allowable mass in a cargohold may be increased by 15% of the maximum mass allowed at the scantling draught in seagoingcondition, but shall not exceed the mass allowed at scantling draught in the seagoing condition. Theminimum required mass may be reduced by the same amount

b) any single cargo hold holding the maximum allowable seagoing mass at 67% of scantling draught, inharbour condition

c) any two adjacent cargo holds carrying MFull, with the next holds being empty, with fuel oil tanks in thedouble bottom in way of the cargo hold, if any, being 100% full and ballast water tanks in the doublebottom in way of the cargo hold being empty, at 67% of scantling draught, in harbour condition.

For HC(M): only item a) applies.For HC(B*): item b) and item c) are less critical than corresponding items a) and b) given in [4.2.5].

4.2.7 Applicable loading patterns depending on qualifiers of the HC notationThe loading patterns to be considered in the direct strength analysis of HC ships are summarised in Table 8.

Table 8 Applicable loading patterns depending on qualifiers of the HC notation

HC HCNo MPLoading pattern Requirement

A B B* C M A B C

Full load in homogeneous condition [4.2.1] item a × × × × x 1) × × ×

Slack load [4.2.1] item b × × × × x 2) × × ×

Deepest ballast [4.2.1] item c × × × × × × × ×

Multiport-1 [4.2.2] item a × × ×

Multiport-2 [4.2.2] item b × × ×

Multiport-3 [4.2.2] item c × × ×

Multiport-4 [4.2.2] item d × × ×

Alternate load partial [4.2.3] items a & b × x 3) ×

Alternate load full [4.2.3] items a & c × x 3) ×

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HC HCNo MPLoading pattern Requirement

A B B* C M A B C

Alternate block load [4.2.3] item d × ×

Heavy ballast [4.2.4] × × x × x × × ×

Harbour condition [4.2.6] × × x 4) × x 5) × × ×

Any hold empty on TSC partially filled condition [4.2.5] items b & e ×

Any hold empty on TSC full condition [4.2.5] items b & f ×

Any hold 1.2MFULL on 0.67TSC partial [4.2.5] items a & e ×

Any hold 1.2MFULL on 0.67TSC full [4.2.5] items a & f ×

Two adjacent holds 1.1MFULLon 0.67TSC [4.2.5] item c ×

Two adjacent holds emptyon 0.75TSC [4.2.5] item d ×

1) MH instead of MFull.2) For ships with special cargo hold arrangement, cargo mass for slack loaded hold may be specially considered.3) Only [4.2.3] if such condition is included in the loading manual, MHD instead of MHD + 0.1MH.4) Only [4.2.6] item a) is relevant as seagoing loading patterns are more decisive for item b) and c).5) Only [4.2.6] item a).

4.2.8 Standard design load combinations for cargo hold FE analysisLoad combinations providing the calculations details for each loading pattern are given in Table 10 to Table 16and summarised in Table 9.

Table 9 Standard FE design load combination tables for HC ships

Midship cargo hold region

HC(A) – EA Table 10

HC(A) – FA Table 11

HC(B) and HC(C) Table 12

HC(B*) Table 13

HC(M) Table 14

HC(M) with alternate loading condition included in loading manual – EA Table 15

HC(M) with alternate loading condition included in loading manual – FA Table 16

Guidance note:Further explanations of the columns in Table 10 to Table 16 are given in the Society's document DNVGL-CG-0127, Finite elementanalysis, [3.4.4].


Guidance note:If cargo hold models of cargo holds outside the midship region, aftmost cargo hold and/or foremost cargo hold is provided, the designload combination tables given in CSR Pt.1 Ch.4 Sec.8 [4.2] may be used as guidance.


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Table 10 FE Load combinations applicable to empty hold in alternate condition (EA) of HC(A) -midship cargo hold region

No.Description

Req. refLoading pattern Aft Mid Fore Draught

% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

Seagoing conditions

1 2) Full load

[4.1.3]

TSC50%(sag.) ≤100%

BSP-1P/S

OST-1P/S

2 1) Full load

[4.2.1] item a

TSC50%(sag.) ≤100% BSP-1P/S

3Slack load

[4.2.1] item b

TSC 0% ≤100% BSP-1P/S

4Slack load

[4.2.1] item b

TSC 0% ≤100% BSP-1P/S

100%(hog.) ≤100%

FSM-2

BSR-1P/S

OST-2P/S5 3)4) Deepest ballast

[4.2.1] item c

THB

100%(sag.) ≤100%

BSP-1P/S

BSR-1P/S

OST-1P/S

6Multiport 3

[4.2.2] item c

0.67TSC100%(sag.) ≤100%

HSM-1

OST-1P/S

7Multiport 3

[4.2.2] item c

0.67TSC100%(sag.) ≤100%

HSM-1

OST-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

100%(hog.) ≤100%

HSM-2

OST-2P/S

8Multiport 4

[4.2.2] item d

0.75TSC100%(sag.) ≤100%

BSP-1P/S

BSR-1P/S

OST-1P/S

100%(hog.) ≤100%

HSM-2

OST-2P/S

9Multiport 4

[4.2.2] item d

0.75TSC100%(sag.) ≤100%

BSP-1P/S

BSR-1P/S

OST-1P/S

100% 9)

Max SFLCFSM-2

100% 10)

Max SFLCFSM-2

100%(hog.)

≤100% OST-2P/S

≤100%BSP-1P/S

OST-1P/S

10 2)

Alternateload partial

[4.2.3] itemsa and b

TSC

0%100% 11)

Max SFLCHSM-1

100% 9)

Max SFLCFSM-2

HSM-2

100% 10)

Max SFLCFSM-2

HSM-2

100%(hog.)

≤100% OST-2P/S

≤100% BSP-1P/S

11

Alternateload full

[4.2.3] itemsa and c

TSC

0% 100% 11)

Max SFLCHSM-1

100%(hog.) ≤100%

FSM-2OST-2P/S

122)5)6)14)

Alt-block load

[4.2.3] item d

TSC100%(sag.) ≤100%

HSM-1BSP-1P/S

OST-1P/S

100%(hog.) ≤100%

FSM-2OST-2P/S

132)5)6)14)

Alt-block load

[4.2.3] item d

TSC100%(sag.) ≤100%

HSM-1BSP-1P/S

OST-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

100% 11)

Max SFLCFSM-2HSM-20%

≤100% BSR-1P/S

100% 9)

Max SFLCHSM-1

100% 10)

Max SFLCHSM-1

14 7) Heavy ballast

[4.2.4]

THB

100%(sag.)

≤100% BSR-1P/S

0% ≤100% BSR-1P/S

15 7)8) Heavy ballast

[4.2.4]

THB 100%(sag.) ≤100% BSR-1P/S

Harbour conditions

100%(hog.) ≤100% N/A

16

Harbourcondition


TH1100%(sag.) ≤100% N/A

100%(hog.) ≤100% N/A

17

Harbourcondition


TH1100%(sag.) ≤100% N/A

100% 12)

Max SFLCN/A

100%(hog.) 100% 13)

Max SFLCN/A

100% 12)

Max SFLCN/A

18

Harbourcondition


TH2

100%(sag.) 100% 13)

Max SFLCN/A

100%(hog.) ≤100% N/A

19 14)

Alt-blockharbourcondition

[4.2.3] item d

TH3100%(sag.) ≤100% N/A

100%(hog.) ≤100% N/A

20 14)


[4.2.3] item d

TH3100%(sag.) ≤100% N/A

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

1) Loading pattern No. 1 with the cargo mass MFull and the maximum cargo density as defined in [4.1.4] can beanalysed in lieu of this loading pattern.

2) Maximum cargo density as defined in [4.1.4] shall be used for calculation of dry cargo pressure.3) In case of no ballast hold, normal ballast condition with assuming MSW = 100% (hog.) shall be analysed.4) Position of ballast hold shall be adjusted as appropriate.5) This condition is only required when this loading condition is included in the loading manual.6) Actual still water vertical bending moment, as given in the loading manual, may be used instead of design value.7) This condition shall be considered for the empty hold which is assigned as ballast hold, if any.8) This condition is not required when this loading condition is explicitly prohibited in the loading manual.9) For the mid-hold where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at aft bulkhead

of the mid-hold.10) For the mid-hold where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at forward

bulkhead of the mid-hold.11) This load combination shall be considered only for the mid-hold where xb-aft>0.5L or xb-fwd<0.5L.12) The shear force shall be adjusted to target value at aft bulkhead of the mid-hold.13) The shear force shall be adjusted to target value at forward bulkhead of the mid-hold.14) This condition is only required when block loading condition is included in the loading manual.

Table 11 FE Load combinations applicable to loaded hold in alternate condition (FA) of HC(A) -midship cargo hold region

No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

Seagoing conditions

1 2) Full load[4.1.3]

TSC50%(sag.) ≤100%

BSP-1P/S

OST-1P/S

2 1) Full load[4.2.1] item a


3Slack load

[4.2.1] item b

TSC 0% ≤100% BSP-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

100%(hog.) ≤100%

FSM-2

BSR-1P/S


[4.2.1] item c

THB

100%(sag.) ≤100%

BSP-1P/S

BSR-1P/S

OST-1P/S

100% 9)

Max SFLCFSM-2

HSM-2

100% 10)

Max SFLCFSM-2

HSM-2

100%(hog.)

≤100% OST-2P/S

100% 11)

Max SFLCHSM-1

5Multiport 2

[4.2.2] item b

0.83TSC

100%(sag.)

≤100%BSP-1P/S

OST-1P/S

6Multiport 3

[4.2.2] item c

0.67TSC100%(sag.) ≤100%

BSP-1P/S

OST-1P/S

7Multiport 3

[4.2.2] item c

0.67TSC100%(sag.) ≤100%

BSP-1P/S

OST-1P/S

100%(hog.) ≤100%

FSM-2

HSM-2

BSR-1P/S

OST-2P/S8Multiport 4

[4.2.2] item d

0.75TSC

100%(sag.) ≤100%

BSP-1P/S

BSR-1P/S

OST-1P/S

100%(hog.) ≤100%

FSM-2

HSM-2

BSR-1P/S


[4.2.2] item d

0.75TSC

100%(sag.) ≤100%

BSP-1P/S

BSR-1P/S

OST-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

100% 11)

Max SFLCFSM-2

HSM-2100%(hog.)

≤100% OST-2P/S

100% 9)

Max SFLCFSM-1

HSM-1

100% 10)

Max SFLCFSM-1

HSM-1

10 2)



TSC

0%

≤100%BSP-1P/S

OST-1P/S

100% 11)

Max SFLCFSM-2

HSM-2100%(hog.)

≤100% OST-2P/S

100% 9)

Max SFLCHSM-1

100% 10)

Max SFLCHSM-1

11

Alternateload full


TSC

0%

100% BSP-1P/S

100%(hog.) ≤100%

FSM-2

HSM-2

OST-2P/S122)5)6)14)

Alt-block load[4.2.3] item d

TSC

100%(sag.) ≤100%

HSM-1

BSP-1P/S

OST-1P/S

100%(hog.) ≤100%

FSM-2

HSM-2

OST-2P/S132)5)6)14)

Alt-block load[4.2.3] item d

TSC

100%(sag.) ≤100%

HSM-1

BSP-1P/S

OST-1P/S

100% 11)

Max SFLCFSM-2

HSM-20%

≤100% BSR-1P/S

100% 9)

Max SFLCHSM-1

14 7) Heavy ballast[4.2.4]

THB

100%(sag.) 100% 10)

Max SFLCHSM-1

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

≤100% BSR-1P/S

0% ≤100% BSR-1P/S

15 7)8) Heavy ballast[4.2.4]

THB 100%(sag.) ≤100% BSR-1P/S

Harbour conditions

100% 12)

Max SFLCN/A

100%(hog.) 100% 13)

Max SFLCN/A

100% 12)

Max SFLCN/A

16 2)

Harbourcondition


TH4

100%(sag.) 100% 13)

Max SFLCN/A

100%(hog.) ≤100% N/A

17Harbourcondition

[4.2.6]item a

0.67TSC100%(sag.) ≤100% N/A

100%(hog.) ≤100% N/A

18Harbourcondition

[4.2.6]item a

0.67TSC100%(sag.) ≤100% N/A

100%(hog.) ≤100% N/A

19

Harbourcondition


TH1100%(sag.) ≤100% N/A

100%(hog.) ≤100% N/A

20

Harbourcondition


TH1100%(sag.) ≤100% N/A

100%(hog.) ≤100% N/A

21 14)


[4.2.3] item d

TH3100%(sag.) ≤100% N/A

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

100%(hog.) ≤100% N/A

22 14)


[4.2.3] item d

TH3100%(sag.) ≤100% N/A

1) Loading pattern no. 1 with the cargo mass MFull and the maximum cargo density as defined in [4.1.4] can beanalysed in lieu of this loading pattern.

2) Maximum cargo density as defined in [4.1.4] shall be used for calculation of dry cargo pressure.3) In case of no ballast hold, normal ballast condition with assuming MSW = 100% (hog.) shall be analysed.4) Position of ballast hold shall be adjusted as appropriate.5) This condition is only required when block loading condition is included in the loading manual.6) Actual still water vertical bending moment, as given in the loading manual, may be used instead of design value.7) This condition shall be considered for the heavy cargo hold which is assigned as ballast hold, if any.8) This condition is not required when this loading condition is explicitly prohibited in the loading manual.9) For the mid-hold where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at aft bulkhead

of the mid-hold.10) For the mid-hold, where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at forward

bulkhead of the mid-hold.11) This load combination shall be considered only for the mid-hold, where xb-aft>0.5L or xb-fwd<0.5L.12) The shear force shall be adjusted to target value at aft bulkhead of the mid-hold.13) The shear force shall be adjusted to target value at forward bulkhead of the mid-hold.14) This condition is only required when block loading condition is included in the loading manual.

Table 12 FE Load combinations applicable for HC(B) and HC(C) - midship cargo hold region

No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

Seagoing conditions

1 1)3) Full load[4.1.3]

TSC50%(sag.) ≤100%

BSP-1P/SOST-1P/S


TSC50%(sag.) ≤100%

BSP-1P/SOST-1P/S

3Slack load

[4.2.1] item b

TSC 0% ≤100% BSP-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

100%(hog.) ≤100%

FSM-2,BSR-1P/SOST-2P/S

4 4)5) Deepest ballast[4.2.1] item c

THB

100%(sag.) ≤100%

BSP-1P/SBSR-1P/S

OST-1P/S

100% 8)

Max SFLCFSM-2HSM-2

100% 9)

Max SFLCFSM-2HSM-2

100%(hog.)

≤100% OST-2P/S

100% 10)

Max SFLCHSM-1

5Multiport 2

[4.2.2] item b

0.83TSC

100%(sag.)

≤100%BSP-1P/SOST-1P/S

6Multiport 3

[4.2.2] item c

0.67TSC100%(sag.) ≤100%

BSP-1P/SOST-1P/S

7Multiport 3

[4.2.2] item c

0.67TSC100%(sag.) ≤100%

BSP-1P/SOST-1P/S

100%(hog.) ≤100%

FSM-2HSM-2

BSR-1P/S


[4.2.2] item d

0.75TSC

100%(sag.) ≤100%

BSP-1P/SBSR-1P/S

OST-1P/S

100%(hog.) ≤100%

FSM-2HSM-2

BSR-1P/S


[4.2.2] item d

0.75TSC

100%(sag.) ≤100%

BSP-1P/SBSR-1P/S

OST-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

100% 10)


≤100% BSR-1P/S

100% 8)

Max SFLCHSM-1

100% 9)

Max SFLCHSM-1


THB

100%(sag.)

≤100% BSR-1P/S

0% ≤100% BSR-1P/S


THB 100%(sag.) ≤100% BSR-1P/S

Harbour conditions

100%(hog.)

≤100% N/A

12Harbourcondition

[4.2.6]item a

0.67TSC100%(sag.)

≤100% N/A

100%(hog.)

≤100% N/A

13Harbourcondition

[4.2.6]item a

0.67TSC100%(sag.)

≤100% N/A

100%(hog.)

≤100% N/A

14

Harbourcondition


TH1100%(sag.)

≤100% N/A

100%(hog.)

≤100% N/A

15

Harbourcondition


TH1100%(sag.)

≤100% N/A

100% 11)

Max SFLCN/A

100%(hog.) 100% 12)

Max SFLCN/A

100% 11)

Max SFLCN/A

16

Harbourcondition


TH2

100%(sag.) 100% 12)

Max SFLCN/A

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

1) Applicable to HC-B only.2) For HC-B ships, the loading pattern no. 1 with the cargo mass MFull and the maximum cargo density as defined in

[4.1.3] can be analysed in lieu of this loading pattern.3) Maximum cargo density as defined in [4.1.3] shall be used for calculation of dry cargo pressure.4) In case of no ballast hold, normal ballast condition with assuming MSW = 100% (hog.) shall be analysed.5) Position of ballast hold shall be adjusted as appropriate.6) This condition shall be considered for the cargo hold which is assigned as ballast hold, if any.7) This condition is not required when this loading condition is explicitly prohibited in the loading manual.8) For the mid-hold where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at aft bulkhead


bulkhead of the mid-hold.10) This load combination shall be considered only for the mid-hold where xb-aft>0.5L or xb-fwd<0.5L.11) The shear force shall be adjusted to target value at aft bulkhead of the mid-hold.12) The shear force shall be adjusted to target value at forward bulkhead of the mid-hold.

Table 13 FE Load combinations applicable to loaded hold in alternate condition of HC(B*) -midship cargo hold region

No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

Seagoing conditions

1 2) Full load[4.1.3]

TSC50%(sag.) ≤100%

BSP-1P/SOST-1P/S



3Slack load

[4.2.1] item b

TSC 0% ≤100% BSP-1P/S

100%(hog.) ≤100%



THB

100%(sag.) ≤100%

BSP-1P/SBSR-1P/S

OST-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

100% 7)

Max SFLCFSM-2

100% 8)

Max SFLCFSM-2

100%(hog.)

≤100% OST-2P/S


5 2)Any hold empty[4.2.5] items

b and e

TSC

0%100% 9)

Max SFLCHSM-1

100% 7)

Max SFLCFSM-2HSM-2

100% 8)

Max SFLCFSM-2HSM-2

100%(hog.)

≤100% OST-2P/S

≤100% BSP-1P/S

6Any hold empty

[4.2.5]items b and f

TSC

0% 100% 9)

Max SFLCHSM-1

100% 9)


(hog.)≤100% OST-2P/S

100% 7)

Max SFLCFSM-1HSM-1

100% 8)

Max SFLCFSM-1HSM-1

7 2)

Any hold1.2MFULL

[4.2.5] itemsa and e

0.67TSC

0%


100% 9)



100% 7)

Max SFLCHSM-1

100% 8)

Max SFLCHSM-1

8

Any hold1.2MFULL

[4.2.5]items a and f

0.67TSC

0%

≤100% BSP-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

9Two adjacentholds 1.1MFULL

[4.2.5] item c

0.67TSC100%(sag.) ≤100%

BSP-1P/SOST-1P/S

10Two adjacentholds 1.1MFULL

[4.2.5] item c

0.67TSC100%(sag.) ≤100%

BSP-1P/SOST-1P/S

100%(hog.) ≤100%

FSM-2HSM-2

BSR-1P/S

OST-2P/S11Two adjacentholds empty

[4.2.5] item d

0.75TSC

100%(sag.) ≤100%

BSP-1P/SBSR-1P/S

OST-1P/S

100%(hog.) ≤100%

FSM-2HSM-2

BSR-1P/S

OST-2P/S12Two adjacentholds empty

[4.2.5] item d

0.75TSC

100%(sag.) ≤100%

BSP-1P/SBSR-1P/S

OST-1P/S

100% 9)


≤100% BSR-1P/S

100% 7)

Max SFLCHSM-1

100% 8)

Max SFLCHSM-1


THB

100%(sag.)

≤100% BSR-1P/S

0% ≤100% BSR-1P/S


THB 100%(sag.) ≤100% BSR-1P/S

Harbour conditions

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

100% 10)

Max SFLCN/A

100%(hog.) 100% 11)

Max SFLCN/A

100% 8)

Max SFLCN/A

15 2)Harbourcondition

[4.2.6] item a

TH4

100%(sag.) 100% 11)

Max SFLCN/A

100%(hog.) ≤100% N/A

16Harbourcondition

[4.2.6] item a

TH1100%(sag.) ≤100% N/A

100%(hog.) ≤100% N/A

17Harbourcondition

[4.2.6] item a

TH1100%(sag.) ≤100% N/A

1) Loading pattern no. 1 with the cargo mass MFull and the maximum cargo density as defined in [4.1.3] can beanalysed in lieu of this loading pattern.

2) Maximum cargo density as defined in [4.1.3] shall be used for calculation of dry cargo pressure.3) In case of no ballast hold, normal ballast condition with assuming MSW = 100% (hog.) shall be analysed.4) Position of ballast hold shall be adjusted as appropriate.5) This condition shall be considered for the cargo hold which is assigned as ballast hold, if any.6) This condition is not required when this loading condition is explicitly prohibited in the loading manual.7) For the mid-hold where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at aft bulkhead


bulkhead of the mid-hold.9) This load combination shall be considered only for the mid-hold, where xb-aft>0.5L or xb-fwd<0.5L.10) The shear force shall be adjusted to target value at aft bulkhead of the mid-hold.11) The shear force shall be adjusted to target value at forward bulkhead of the mid-hold.

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Table 14 FE Load combinations applicable to HC(M) ships not having alternate loading conditionsincluded in the loading manual - midship cargo hold region

No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

Seagoing conditions

1 2) Full load[4.1.3]

TSC50%(sag.) ≤100%

BSP-1P/SOST-1P/S


TSC50%(sag.) ≤100%

BSP-1P/SOST-1P/S

3Slack load

[4.2.1] item b

TSC 0% ≤100% BSP-1P/S

100%(hog.) ≤100%

FSM-2BSR-1P/S


[4.2.1] item c

THB

100%(sag.) ≤100%

BSP-1P/SBSR-1P/S

OST-1P/S

100% 9)


≤100% BSR-1P/S

100% 7)

Max SFLCHSM-1

100% 8)

Max SFLCHSM-1


THB

100%(sag.)

≤100% BSR-1P/S

0% ≤100% BSR-1P/S


THB 100%(sag.) ≤100% BSR-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

1) Loading pattern No. 1 with the cargo mass MH and the maximum cargo density as defined in [4.1.4] can beanalysed in lieu of this loading pattern.



bulkhead of the mid-hold.9) This load combination shall be considered only for the mid-hold, where xb-aft>0.5L or xb-fwd<0.5L.

Table 15 FE Load combinations applicable to empty hold in alternate condition (EA) of HC(M)ships having alternate loading conditions included in the loading manual - midship cargo holdregion

No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

Seagoing conditions

1 2) Full load[4.1.3]

TSC50%(sag.) ≤100%

BSP-1P/SOST-1P/S



3Slack load

[4.2.1] item b

TSC 0% ≤100% BSP-1P/S

4Slack load

[4.2.1] item b

TSC 0% ≤100% BSP-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

100%(hog.) ≤100%



THB

100%(sag.) ≤100%

BSP-1P/SBSR-1P/S

OST-1P/S

100% 7)

Max SFLCFSM-2

100% 8)

Max SFLCFSM-2

100%(hog.)

≤100% OST-2P/S


6 2)



TSC

0%100% 9)

Max SFLCHSM-1

100% 7)

Max SFLCFSM-2HSM-2

100% 8)

Max SFLCFSM-2HSM-2

100%(hog.)

≤100% OST-2P/S

≤100% BSP-1P/S

7

Alternateload full


TSC

0% 100% 9)

Max SFLCHSM-1

100% 9)


≤100% BSR-1P/S

100% 7)

Max SFLCHSM-1

100% 8)

Max SFLCHSM-1


THB

100%(sag.)

≤100% BSR-1P/S

0% ≤100% BSR-1P/S


THB 100%(sag.) ≤100% BSR-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case




bulkhead of the mid-hold.9) This load combination shall be considered only for the mid-hold where xb-aft>0.5L or xb-fwd<0.5L.

Table 16 FE Load combinations applicable to loaded hold in alternate condition (FA) of HC(M)ships having alternate loading conditions included in the loading manual - midship cargo holdregion

No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

Seagoing conditions

1 2) Full load[4.1.3]

TSC50%(sag.) ≤100%

BSP-1P/SOST-1P/S



3Slack load

[4.2.1] item b

TSC 0% ≤100% BSP-1P/S

100%(hog.) ≤100%

FSM-2BSR-1P/SOST-2P/S


THB

100%(sag.) ≤100%

BSP-1P/SBSR-1P/S

OST-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

100% 9)



100% 7)

Max SFLCFSM-1HSM-1

100% 8)

Max SFLCFSM-1HSM-1

5 2)



TSC

0%


100% 9)



100% 7)

Max SFLCHSM-1

100% 8)

Max SFLCHSM-1

6

Alternateload full


TSC

0%

≤100% BSP-1P/S

100% 9)


≤100% BSR-1P/S

100% 7)

Max SFLCHSM-1

100% 8)

Max SFLCHSM-1


THB

100%(sag.)

≤100% BSR-1P/S

0% ≤100% BSR-1P/S


THB 100%(sag.) ≤100% BSR-1P/S

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No.Description


% ofperm.SWBM

% ofperm.SWSF

Dynamicload case




bulkhead of the mid-hold.9) This load combination shall be considered only for the mid-hold where xb-aft>0.5L or xb-fwd<0.5L.

4.3 Standard loading conditions for fatigue assessment

4.3.1 The standard loading conditions to be applied to for fatigue assessment are defined in Table 17 to Table20 according to their HC notations.



Table 17 Standard design FE Load combinations for fatigue assessment applicable to empty holdin alternate condition (EA) of HC(A) and HC(M) (if specified in the loading manual) - midshipcargo hold region

No. Description Loading pattern Aft Mid Fore Draught% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

1-F 1) Full loadhomogeneous

TSC40%(sag.) All

2-F 2) Full loadalternate

TSC75%

(hog.) ≤100% All

3-F 1) Normal ballast

TBAL80%

(hog.) All

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% ofperm.SWSF

Dynamicload case

1) The actual shear force curve that results from the application of static and dynamic local loads to the FE model shallbe used.

2) The actual shear force curve that results from the application of static and dynamic local loads to the FE model shallbe used. Where this shear force exceeds the target value, the correction of vertical loads shall be applied to adjustthe shear force down to the target value.

Table 18 Standard design FE Load combinations for fatigue assessment applicable to loaded holdin alternate condition (FA) of HC(A) and HC(M) (if specified in the loading manual) - midshipcargo hold region


% ofperm.SWSF

Dynamicload case


TSC40%(sag.) All


TSC75%

(hog.) ≤100% All


TBAL80%

(hog.) All

1) The actual shear force that results from the application of static and dynamic local loads to the FE model shall beused.

2) The actual shear force that results from the application of static and dynamic local loads to the FE model shall beused. Where this shear force exceeds the target value, the correction of vertical loads shall be applied to adjust theshear force down to the target value.

Table 19 Standard design FE load combinations for fatigue assessment of HC(B), HC(C) and HC(M)(if alternate conditions are not specified in the loading manual) - midship cargo hold region


% ofperm.SWSF

Dynamicload case


TSC40%(sag.) All

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% ofperm.SWSF

Dynamicload case


TBAL80%

(hog.) All

1) The actual shear force curve that results from the application of static and dynamic local loads to the FE model shallbe used.

2) The actual shear force curve that results from the application of static and dynamic local loads to the FE model shallbe used. Where this shear force exceeds the target value, the correction of vertical loads shall be applied to adjustthe shear force down to the target value.

Table 20 Standard design FE Load combinations for fatigue assessment applicable to BC(B*) -midship cargo hold region


% ofperm.SWSF

Dynamicload case


TSC40%(sag.) All


TSC75%

(hog.) ≤100% All


TBAL80%

(hog.) All

1) The actual shear force that results from the application of static and dynamic local loads to the FE model shall beused.

2) The actual shear force that results from the application of static and dynamic local loads to the FE model shall beused. Where this shear force exceeds the target value, the correction of vertical loads shall be applied to adjust theshear force down to the target value.

5 Hold mass curves

5.1 Introduction5.1.1 ScopeThis sub-section describes the procedure to be used for determination of:

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— the maximum and minimum mass of cargo in each cargo hold as a function of the draught at mid-holdposition of cargo hold

— the maximum and minimum mass of cargo in any two adjacent holds as a function of the draught at mid-length of these two adjacent cargo holds.

5.1.2 Relations with the design loading criteriaThe maximum allowable or minimum required cargo mass in a cargo hold, or in two adjacent loaded holdsis related to the net load on the double bottom. The net load on the double bottom is a function of draught,cargo mass in the cargo hold, as well as the mass of fuel oil and ballast water contained in double bottomtanks.Based on the design loading criteria, as given in [4.2.1] to [4.2.6], hold mass curves for each single hold, aswell as for any two adjacent holds shall be included in the loading manual and the loading instrument.If the ship structure is checked for more severe loading conditions than the ones considered in [4.2.8], theminimum required cargo mass and the maximum allowable cargo mass can be based on those correspondingloading conditions.

5.1.3 Loading/unloading conditions in harbourThe maximum permissible cargo mass and the minimum required cargo mass of single cargo hold or of twoadjacent cargo holds, corresponding to draught for loading/unloading conditions in harbour may be increasedor decreased by 15% of the maximum permissible mass at the maximum draught for the cargo hold inseagoing condition. However, maximum permissible mass is in no case to be greater than the maximumpermissible cargo mass at designed maximum load draught for each cargo hold.

5.1.4 Maximum and minimum permissible mass expressionThe maximum and minimum permissible mass in seagoing conditions, (WmaxS(T), WminS(T)) and in harbourcondition ((WmaxH(T), WminH(T)) at various draughts (T) is obtained, in t, by the following formulae given intables of [5.2] and [5.3] for the following:

— HC(A) ships not having No MP notation assigned— HC(A) ships having No MP notation assigned— HC(B) and HC(C) ships not having No MP notation assigned— HC(B) and HC(C) ships having No MP notation assigned— HC(B*) ships— HC(M) ships not having alternate loading conditions included in the loading manual— HC(M) ships having alternate loading conditions included in the loading manual.

5.2 Single cargo hold5.2.1 HC(A) ships not having No MP notation assignedMaximum permissible mass and minimum required mass of single cargo hold of HC(A) ships not having NoMP notation assigned, applicable to full hold in alternate condition (FA) and empty in alternate condition(EA), are shown in Table 21.

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Table 21 HC(A) ships not having No MP notation assigned

Hold Loadingconditions Max / Min curves Curve

Ref Ref

Maximum:

I [4.2.3] b & c

SeagoingMinimum:

II [4.2.2] b

Maximum:

III-1III-2

[4.2.6] b[4.2.6] a

FA

Harbour

Minimum:

IV [4.2.6] b

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Ref Ref

Maximum

I [4.2.2] a

SeagoingMinimum:

II [4.2.3] a

Maximum

III [4.2.6] a

EA

HarbourMinimum:

IV [4.2.6] a

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Ref Ref

5.2.2 HC(A) ships having No MP notation assignedMaximum permissible mass and minimum required mass of single cargo hold of HC(A) ships having No MPnotation assigned, applicable to full hold in alternate condition (FA) and empty in alternate condition (EA),are shown in Table 22.

Table 22 HC(A) ships having No MP notation assigned


Ref Ref

FA Seagoing

Maximum:

I [4.2.3] b & c

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Ref Ref

Minimum:

II-1II-2

[4.2.1] c[4.2.1] b

Maximum:

III-1III-2

[4.2.6] b[4.2.6] a

Harbour

Minimum:

IV [4.2.6] a

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Ref Ref

Maximum

I [4.2.1] a

SeagoingMinimum:

II [4.2.3] a

Maximum

III-1III-2

[4.2.6] b[4.2.6] a

EA

Harbour

Minimum:

IV [4.2.6] a

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Ref Ref

5.2.3 HC(B) and HC(C) ships not having No MP notation assignedMaximum permissible mass and minimum required mass of single cargo hold of HC(B) and HC(C) ships nothaving No MP notation assigned, are shown in Table 23.

Table 23 HC(B) and HC(C) ships not having No MP notation assigned

Loading conditions Max / Min curves CurveRef Ref

Maximum

I [4.2.2] a

SeagoingMinimum:

II [4.2.2] b

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Maximum

III [4.2.6] a

HarbourMinimum:

IV [4.2.6] a

5.2.4 HC(B) and HC(C) ships having No MP notation assignedMaximum permissible mass and minimum required mass of single cargo hold of HC(B) and HC(C) shipshaving No MP notation assigned, are shown in Table 24.

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Table 24 HC(B) and HC(C) ships having No MP notation assigned


Maximum:

I [4.2.1] a

SeagoingMinimum:

II-1II-2

[4.2.1] c[4.2.1] b

Maximum:

III-1III-2

[4.2.6] b[4.2.6] a

Harbour

Minimum:

IV [4.2.6] a

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5.2.5 HC(B*) shipsMaximum permissible mass and minimum required mass of single cargo hold of HC(B*) ships are shown inTable 25.

Table 25 HC(B*) ships


Maximum

I [4.2.5] a

SeagoingMinimum:

II [4.2.5] b

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Maximum

III [4.2.6] a

HarbourMinimum:

IV [4.2.6] a

5.2.6 HC(M) ships not having alternate loading conditions included in the loading manualMaximum permissible mass and minimum required mass of single cargo hold of HC(M) ships not havingalternate loading conditions included in the loading manual, are shown in Table 26.

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Table 26 HC(M) ships not having alternate loading conditions included in the loading manual


Maximum:

I [4.2.1] a

SeagoingMinimum:

II-1II-2

[4.2.1] c[4.2.1] b

Maximum:

III [4.2.6] a

HarbourMinimum:

IV [4.2.6] a

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5.2.7 HC(M) ships having alternate loading conditions included in the loading manualMaximum permissible mass and minimum required mass of single cargo hold of HC(M) ships havingalternate loading conditions included in the loading manual, applicable to full hold in alternate condition (FA)and empty in alternate condition (EA), are shown in Table 27.

Table 27 HC(M) ships having alternate loading conditions included in the loading manual

Hold Loading conditions Max / Min curves CurveRef Ref

FA Seagoing

Maximum:

I [4.2.3] b & c

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Minimum:

II-1II-2

[4.2.1] c[4.2.1] b

Maximum:

III [4.2.6] a

HarbourMinimum:

IV [4.2.6] a

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Maximum

I [4.2.1] a

SeagoingMinimum:

II [4.2.3] a

Maximum:

III [4.2.6] a

HarbourMinimum:

IV [4.2.6] a

EA

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5.3 Two adjacent holds5.3.1 HC(A) ships not having No MP notation assignedMaximum permissible mass and minimum required mass of two adjacent holds of HC(A) ships not having NoMP notation assigned, are shown in Table 28.

Table 28 HC(A) ships not having No MP notation assigned

Loadingconditions Max / Min curves Curve

Ref Ref

Maximum:

I-11)

I-2[4.2.3] d[4.2.2] c

Seagoing

Minimum:

II [4.2.2] d

Maximum:

III-11)

III-2[4.2.6] a[4.2.6] a

HarbourMinimum:

IV-11)

IV-2[4.2.6] a[4.2.6] a

1) This limit curve is only applicable when block loading condition is included in the loading manual.

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Ref Ref

5.3.2 HC(A) ships having No MP notation assignedMaximum permissible mass and minimum required mass of two adjacent holds of HC(A) ships having NoMP notation assigned, are shown in Table 29.

Table 29 HC(A) ships having No MP notation assigned


Ref Ref

Seagoing

Maximum:

I-11)

I-2[4.2.3] d[4.2.2] a

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Ref Ref

Minimum:

II-1II-2

[4.2.2] c[4.2.2] b

Maximum:

III-11)

III-2

III-3

[4.2.6] a[4.2.6] c

[4.2.6] a

Harbour

Minimum:

IV-11)

IV-2[4.2.6] a[4.2.6] a

1) This limit curve is only applicable when block loading condition is included in the loading manual.

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Ref Ref

5.3.3 HC(B) and HC(C) ships not having No MP notation assignedMaximum permissible mass and minimum required mass of two adjacent holds of HC(B) and HC(C) shipsnot having (No MP) notation assigned, are shown in Table 30.

Table 30 HC(B) and HC(C) ships not having No MP notation assigned


Ref Ref

Maximum:

I [4.2.2] c

SeagoingMinimum:

II [4.2.2] d

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Ref Ref

Maximum:

III [4.2.6] a

HarbourMinimum:

IV [4.2.6] a

5.3.4 HC(B) and HC(C) ships having No MP notation assignedMaximum permissible mass and minimum required mass of two adjacent holds of HC(B) and HC(C) shipshaving (No MP) notation assigned, are shown in Table 31.

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Table 31 HC(B) and HC(C) ships having No MP notation assigned


Ref Ref

Maximum:

I [4.2.1] a

Seagoing

Minimum:

II-1II-2

[4.2.1] c[4.2.1] b

Maximum:

III-1III-2

[4.2.6] b[4.2.6] a

Harbour

Minimum:

IV [4.2.6] a

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Ref Ref

5.3.5 HC(B*) shipsMaximum permissible mass and minimum required mass of two adjacent holds of HC(B*) ships are shown inTable 32.

Table 32 HC(B*) ships


Ref Ref

Maximum:

I [4.2.5] c

SeagoingMinimum:

II [4.2.5] d

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Ref Ref

Maximum:

III [4.2.6] a

HarbourMinimum:

IV [4.2.6] a

5.3.6 HC(M) shipsMaximum permissible mass and minimum required mass of two adjacent holds of HC(M) ships are shown inTable 29.

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Table 33 HC(M) ships


Ref Ref

Maximum:

I

[4.2.1] a

SeagoingMinimum:

II-1II-2

[4.2.1] c[4.2.1] b

Maximum:

III [4.2.6] a

HarbourMinimum:

IV [4.2.6] a

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Ref Ref

6 Hull local scantling

6.1 Plating6.1.1 Plating subject to lateral pressureThe requirements given in Pt.3 Ch.6 Sec.4 [1] shall be complied with, applying the additional design loadsets given in Pt.5 Ch.1 Sec.2 [5.1], with mass and density in accordance with [3.2].

6.2 Stiffeners6.2.1 Stiffeners subject to lateral pressureThe requirements given in Pt.3 Ch.6 Sec.5 [1] shall be complied with, applying the additional design loadsets given in Pt.5 Ch.1 Sec.2 [5.1], with mass and density in accordance with [3.2].

6.3 Intersection of stiffeners and primary supporting members6.3.1 Connection of stiffeners to primary supporting membersThe requirements for connection of stiffeners to primary supporting members shall comply with Pt.3 Ch.6Sec.7 [1] with internal pressures due to dry bulk cargo in accordance with Pt.5 Ch.1 Sec.2 [3], applyingcargo mass and density given in [3.2].

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7 Finite element analysis

7.1 Cargo hold analysis7.1.1 GeneralCargo hold analysis shall be carried out in accordance with Pt.5 Ch.1 Sec.5 [7.2] using detailed requirementsgiven in the following sub-sections.

7.1.2 FE load combinationsApplicable FE load combinations are given in [4.2.8].

7.1.3 Internal loadsBulk pressures and shear loads in accordance with Pt.5 Ch.1 Sec.2 [3], with mass and density in accordancewith [3.2], shall be applied to the FE model.

7.2 Local structural strength analysis7.2.1 GeneralLocal structural strength analysis shall be carried out in accordance with Pt.3 Ch.7 Sec.4 using detailedrequirements given in the following sub-sections.

Guidance note:Calculation methods acceptable to the Society are further outlined in the Society's document DNVGL-CG-0127, Finite element analysis.


7.2.2 ApplicationLocal structural strength analysis by use of finite element analysis shall be carried out within the midshipregion for the following member:

— one longitudinal section with connections between inner bottom and bottom longitudinal stiffeners, andadjoining structures of transverse bulkhead, subject to maximum relative displacement between supports.


7.2.4 Internal loadsBulk pressures and shear loads in accordance with Pt.5 Ch.1 Sec.2 [3], with mass and density in accordancewith [3.2], shall be applied to the FE model.

8 Buckling

8.1 Hull girder bucklingThe requirements given in Pt.3 Ch.8 Sec.3 shall be complied with, applying the additional design load setsgiven in Pt.5 Ch.1 Sec.2 [5.1], with mass and density in accordance with [3.2].

9 Fatigue

9.1 Fatigue strength calculations

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9.1.1 GeneralFatigue assessment shall be carried out in accordance with Pt.3 Ch.9 using detailed requirements in thefollowing sub-sections.

Guidance note:Calculation methods acceptable to the Society are further outlined in the Society's document DNVGL-CG-0129, Fatigue assessmentof ship structure.


9.1.2 Loading conditionsParameters as input to the fatigue calculation shall be in accordance with Pt.3 Ch.9 Sec.4 Table 2, withspecific parameters for HC ships given in Table 34.Radius of gyration, kr, and metacentric height, GM, shall be in accordance with Pt.5 Ch.1 Sec.2 Table 4.Dry cargo mass and density shall be in accordance with [3.2].

Table 34 Standard values to be used for fatigue analysis

HC notation HC(A), HC(B*) andHC(M)with alternate loading

HC(B), HC(C) andHC(M) withoutalternate loading

α, full load homogeneous condition 0.3 0.5

α, full load alternate condition 0.3 NA

α, ballast condition 0.4 0.5

Draft, full load homogeneous condition Tsc Tsc

Draft, full load alternate condition Tsc NA

Draft, ballast condition TBal TBal

β; Msw, FLS, full load homogeneous condition 40% (sag.) 40% (sag.)

β; Msw, FLS, full load alternate condition 75% (hog.) NA

β; Msw, FLS, ballast condition 80% (hog.) 80% (hog.)

9.2 Prescriptive fatigue strength assessment9.2.1 GeneralWithin the cargo region, the fatigue life of longitudinal end connections in way of web frames and transversebulkheads shall be assessed in accordance with the Society's document DNVGL-CG-0129 Fatigue assessmentof ship structure. The following stress components shall be considered in the fatigue assessment:

— DNVGL-CG-0129 [4.4]: stress due to global hull girder stress— DNVGL-CG-0129 [4.6]: local stiffener bending stress— local relative deflection stress in accordance with [8.2.2].

9.2.2 Local relative deflection stressThe effect of relative deflection of stiffener end connections in way of transverse bulkhead within the midshipregion shall be taken into account in the fatigue strength assessment according to the Society's documentDNVGL-CG-0129, Fatigue assessment of ship structure, [4.7].Standard fatigue loading conditions as given in [4.3.1] shall be applied to the midship FE cargo hold model.

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9.3 Finite element stress analysis9.3.1 Application and scopeWithin the midship region, the connection between the inner bottom and the longitudinal bulkhead or hopperplating in way of floors, being a web-stiffened cruciform joint, shall be assessed in accordance with theSociety's document DNVGL-CG-0129, Fatigue assessment of ship structure, [6.5.2].Standard fatigue loading conditions as given in [4.3.1] shall be applied to the stress concentration model.

10 Loading manual and loading instrument

10.1 Loading manual10.1.1 General requirementsThe requirements given in the following sub-sections apply in addition to Pt.3 Ch.1 Sec.5 [2.1].

10.1.2 Requirements specific to dry cargo shipsThe loading manual shall contain the loading conditions described in [4].The loading manual shall describe:

— envelope results and permissible limits of still water bending moments and shear forces in the holdflooded condition, where applicable, see Pt.5 Ch.1 Sec.4

— the cargo hold(s) or combination of cargo holds that might be empty at full draught. If no cargo hold isallowed to be empty at full draught, this shall be clearly stated in the loading manual

— maximum allowable and minimum required mass of cargo and double bottom contents of each hold as afunction of the draught at mid-hold position, see [5.2]

— maximum allowable and minimum required mass of cargo and double bottom contents of any twoadjacent holds as a function of the mean draught in way of these holds. This mean draught may becalculated by averaging the draughts at the two mid-hold positions, see [5.3]

— maximum allowable tank top loading together with specification of the nature of the cargo for cargoesother than bulk cargoes

— maximum allowable load on deck and hatch covers. If the ship is not approved to carry load on deck orhatch covers, this shall be clearly stated in the loading manual

— maximum rate of ballast change together with the advice that a load plan shall be agreed with theterminal on the basis of the achievable rates of change of ballast.

The additional following loading conditions, subdivided into departure and arrival conditions as appropriate,shall be included in the loading manual:

— homogeneous light and heavy cargo loading conditions at maximum draught— alternate light and heavy cargo loading conditions at maximum draught, where applicable— ballast conditions. For ships having ballast holds adjacent to topside wing, hopper and double bottom

tanks, it shall be strengthwise acceptable that the ballast holds are filled when the topside wing, hopperand double bottom tanks are empty

— short voyage conditions where the ship shall be loaded to maximum draught but with a limited amount ofbunkers

— multiple port loading/unloading conditions— deck cargo conditions, where applicable— typical sequences for change of ballast at sea, where applicable— typical loading sequences where the ship is loaded from commencement of cargo loading to reaching full

deadweight capacity, for homogeneous conditions, relevant part load conditions and alternate conditionswhere applicable. Typical unloading sequences for these conditions are also to be included. The typicalloading/unloading sequences are also to be developed so as not to exceed applicable strength limitations.

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The typical loading sequences are also to be developed paying due attention to loading rate and thedeballasting capability. Figure 1 contains, as guidance only, an example of a loading sequence summaryform.

10.2 Loading instrument10.2.1 General requirementsThe requirements given in the following sub-section applies in addition to Pt.3 Ch.1 Sec.5 [3.1].

10.2.2 Requirements specific to dry cargo shipsThe loading instrument shall ascertain as applicable:

— the mass of cargo and double bottom contents in way of each hold as a function of the draught at mid-hold position does not exceed the allowable loading defined by the hold mass curves

— the mass of cargo and double bottom contents of any two adjacent holds as a function of the meandraught in way of these holds does not exceed the allowable loading defined by the hold mass curves

— that the still water bending moment and shear forces in the hold flooded conditions do not exceed thespecified permissible values, where applicable.

The approval shall include, as applicable:

— acceptance of hull girder bending moment limits for all read-out points— acceptance of hull girder shear force limits for all read-out points— acceptance of limits for the mass of cargo and double bottom contents of each hold as a function of

draught— acceptance of limits for the mass of cargo and double bottom contents in any two adjacent holds as a

function of draught.

10.3 Guidance for loading/unloading sequences

10.3.1 The typical loading/unloading sequences shall be developed paying due attention to the loading/unloading rate, the ballasting/deballasting capacity and the applicable strength limitations.

10.3.2 The typical loading sequences as relevant shall include:

— alternate light and heavy cargo load condition— homogeneous light and heavy cargo load condition— short voyage condition where the ship is loaded to maximum draught but with limited bunkers— multiple port loading/unloading condition— deck cargo condition— block loading.

10.3.3 The loading/unloading sequences may be port specific or typical.

10.3.4 The sequence shall be built up step by step from commencement of cargo loading to reach fulldeadweight capacity. Each time the loading equipment changes position to a new hold defines a step.Each step shall be documented and submitted to the Society. In addition to longitudinal strength, the localstrength of each hold shall be considered.

10.3.5 For each loading condition, a summary of all steps shall be included. This summary shall highlight theessential information for each step, such as:

— how much cargo is filled in each hold during the different steps— how much ballast is discharged from each ballast tank during the different steps— the maximum still water bending moment and shear force at the end of each step

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— the ship’s trim and draught at the end of each step.

Rules for classification: S

hips — D

NVG

L-RU

-SH

IP-Pt6Ch1. Edition O

ctober 2015Page 83

Structural strength and integrity

DN

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Part 6 Chapter 1 Section 4

Figure 1 Loading Sequence Summary Form

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SECTION 5 STRENGTHENED FOR ORE CARGO - OC

1 General

1.1 IntroductionAdditional class notation OC includes design requirements for cargo ships intended for the carriage of ore.Strengthening of these types of ship will be determined by conditions related to the intended trading pattern,i.e. homogeneous or additional strengthening for loading and unloading in multiple ports.

1.2 ScopeThe scope of class notation OC is to add an additional level of safety in relation to the strengthening of thehull structure due to the carriage of ore cargo. The rules in this section are considered to satisfy the designrequirements based on the given rule defined loading flexibility, depending upon selected qualifiers, seeTable1.This section includes requirements for hull strength, including:

— [3]: Pressures and forces due to dry bulk cargo— [4]: Loading conditions— [5]: Hold mass curves— [6]: Hull local scantling— [7]: Finite element analysis— [8]: Buckling— [9]: Fatigue— [10]: Loading manual and loading instrument.

1.3 ApplicationOne of the OC class notations specified in this section shall be applied to ships assigned the ship typenotation Ore carrier having a length L of not less than 150 m.

1.4 Class notations1.4.1 OCShips built in compliance with the requirements as specified in Table 1 will be assigned the additional notationrelated to structural strength and integrity as follows:

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Table 1 Additional class notation - OC


MStrengthened for loading andunloading in multiple ports, inaddition to OC(H)

Mandatory for Ore carrier with L ≥ 150 m,unless OC(H) is assigned

OC

Mandatory:

Yes


[3] to [10]

FiS requirements:

NA

HDesigned to carry ore cargoesin seagoing homogeneousloading conditions

Mandatory for Ore carrier with L ≥ 150 m,unless OC(M) is assigned

1.4.2 Holds n may be emptyShips built in compliance with the requirements as specified in Table 2 will be assigned the additional notationrelated to structural strength and integrity as follows:

Table 2 Additional class notation - Holds n may be empty


Holds n may be empty

Mandatory:

Yes


[4.1.3]

FiS requirements:

NA

<None>

Holds may be empty atmaximum draught among theseagoing loading conditionsin the loading manual withspecified holds empty, wheren is the identification numberfor each hold that may beempty

Mandatory for ships with Class Notation OC(M)


h = vertical distance from the top of inner bottom plating to the lowest point of theupper deck plating at the ship’s centreline, in m

ha = vertical distance from the top of inner bottom plating to the lowest point of theupper deck plating at the ship’s centreline of the aft cargo hold of two adjacentcargo holds, in m

hf = vertical distance from the top of inner bottom plating to the lowest point of theupper deck plating at the ship’s centreline of the fore cargo hold of two adjacentcargo holds, in m

MH = cargo mass, in t, as defined in Pt.5 Ch.1 Sec.2Ti = draught, horizontal axis for the hold mass curves, in m, at mid-hold position of

single cargo hold length or at mid-length of the two adjacent cargo holds considered

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THB = deepest ballast draught, in m, at mid-hold position of single cargo hold length or atmid-length of the two adjacent cargo holds considered

TLB = lightest ballast draught, in m, at mid-hold position of single cargo hold length or atmid-length of the two adjacent cargo holds considered

TS,MIN,FULL,HAR = minimum draught, in m, at mid-hold position of single cargo hold with MH in harbourcondition given in the loading and unloading sequences

TADJ,MIN,FULL,HAR = minimum draught, in m, at mid-length of the two adjacent cargo holds consideredwith ΣMH in harbour condition given in the loading and unloading sequences

TS,MAX,EMPTY,HAR = maximum draught, in m, at mid-hold position of single cargo hold being empty inharbour condition given in the loading and unloading sequences

TADJ,MAX,EMPTY,HAR = maximum draught, in m, at mid-length of the two adjacent cargo holds consideredwith adjacent holds being empty in harbour condition given in the loading andunloading sequences

TS,MIN,ALT,SEA = minimum draught, in m, at mid-hold position of single cargo hold with MH inalternate seagoing condition given in the loading manual

TS,MAX,ALT,SEA = maximum draught, in m, at mid-hold position of single cargo hold being empty inalternate seagoing condition given in the loading manual

TADJ,MIN,ALT,SEA = minimum draught, in m, at mid-length of the two adjacent cargo holds considered inalternate seagoing condition given in the loading manual

TADJ,MAX,ALT,SEA = maximum draught, in m, at mid-length of the two adjacent cargo holds consideredin alternate seagoing condition given in the loading manual

TMAX,EMPTY,WBE = maximum draught, in m, at mid-hold position of single cargo hold being empty, withwing ballast tank empty across, in seagoing condition according to the sequentialwater ballast exchange procedures

VH = volume in m3, as defined in Pt.5 Ch.1 Sec.2Va = volume of the after cargo hold of two adjacent cargo holds excluding volume of the

hatchway part, in m3

Vf = volume of the forward cargo hold of two adjacent cargo holds excluding volume ofthe hatchway part, in m3

Σ = the sum of masses of two adjacent cargo holdsEA = empty hold in alternate loading conditionFA = full hold in alternate loading condition.

2 Documentation

2.1 Documentation requirements2.1.1 OCDocumentation shall be submitted as required by Table 3.

Table 3 Documentation requirements - OC


H112 – Loading sequence description,preliminary AP, VS

Ship hull structure

H114 – Loading sequence description, final AP, VS



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3 Pressures and forces due to dry bulk cargo

3.1 GeneralPressures and forces due to dry bulk cargo shall be in accordance with Pt.5 Ch.1 Sec.2 [3], applying cargomass and density given in [3.2].

3.2 Mass and density— for strength assessment: the values defined in Table 4— for fatigue assessment: the values defined in Table 5.

Table 4 Dry bulk cargo mass and density for strength assessment

Homogeneous loading condition Alternate loading conditionOC

Cargo massCargo density Fully filled hold Partially filled hold Fully filled hold Partially filled hold

M M = MH M = MH

OC(H)ρC

ρC = 3.0N/A

M M = MH M = MH M = MH M = MH

OC(M)ρC

ρC = 3.0

ρC = 3.0

Table 5 Dry bulk cargo mass and density for fatigue assessment

OC Cargo mass Cargo densityHomogeneous loading condition,

partially filled hold

M M = MHOC(H)

ρC ρC = 3.0

M M = MHOC(M)

ρC ρC = 3.0

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4 Loading conditions

4.1 Specific design loading conditions4.1.1 GeneralThe seagoing loading conditions given in [4.1.2] to [4.1.5]shall be included, as a minimum, in the loadingmanual.

4.1.2 Cargo loading condition for OC(H)Homogeneous cargo loaded condition shall be included in the loading manual where the cargo density istaken equal to 3.0 t/m3 in all cargo holds at scantling draught.

4.1.3 Cargo loading condition for OC(M)As required for OC(H), plus:At least one cargo loaded condition with specified holds empty, with all loaded cargo holds having loadingaccording to [4.1.2], at reduced draught.The combination of specified empty holds shall be indicated with the additional notation Holds n may beempty.

4.1.4 Light ballast conditionThe ship shall have a light ballast condition where:

1) the ballast tanks may be full, partially full or empty. Where partially full option is exercised, theconditions in [4.1.6] shall be complied with

2) the propeller shall be fully immersed3) the structures of bottom forward shall be strengthened in accordance with Pt.3 Ch.10 Sec.2 against

slamming for the condition listed above at the lightest forward draught TF4) the longitudinal strength requirements shall be met for the conditions listed above.

4.1.5 Heavy ballast conditionThe vessel shall have a heavy ballast condition where:

1) all ballast tanks within the cargo hold region are full or partially full. Where partially full option isexercised, the conditions in [4.1.6] shall be complied with

2) the longitudinal strength requirements shall be met for the condition listed above.

4.1.6 Partially filled ballast tanks in ballast loading conditionsThe requirements in Pt.3 Ch.4 Sec.8 [1.2.1] apply in general.

For conventional ore carriers with large wing water ballast tanks in the cargo region, where empty or fullballast water filling levels of one or maximum two pairs of these tanks lead to the ship's trim exceeding oneof the following criteria, it is sufficient to demonstrate compliance with maximum, minimum and intendedpartial filling levels of one or maximum two pairs of ballast tanks such that the ship's trim does not exceedany of these trim limits. Filling levels of all other wing ballast tanks shall be considered between empty andfull. The trim conditions mentioned above are:

— trim by stern of 0.03 L, or— trim by bow of 0.015 L, or— any trim that cannot maintain propeller immersion (I/D) not less than 25%.

where:

I the distance from propeller centerline to the waterline, in m.D propeller diameter, in m.

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See Figure 1.

The maximum and minimum filling levels of the above mentioned pairs of side ballast tanks shall be indicatedin the loading manual.

Figure 1 Propeller immersion

4.2 Design load combinations for direct strength analysis4.2.1 Applicable general seagoing loading patternsThe following loading patterns shall be applied:

a) any cargo hold carrying MH, with all double bottom fuel oil tanks in way of the cargo hold, if any, being100% full, at scantling draught TSC

b) any cargo hold taken empty, with all double bottom tanks in way of the cargo hold, if any, being empty,at the deepest ballast draught THB

c) any two adjacent cargo holds carrying MH, with all double bottom fuel oil tanks in way of the adjacentcargo holds, if any, being 100% full, at scantling draught TSC

d) any two adjacent cargo holds being empty, with all double bottom tanks in way of the adjacent cargoholds, if any, being empty, at the deepest ballast draught THB

e) any wing ballast tank being 100% full, with fuel oil tanks in wing space, if any, being 100% full, at thelightest ballast draught TLB

f) any wing ballast tank being empty, with fuel oil tanks in wing space, if any, being empty, at scantlingdraught TSC

g) the deck girder structures and the web frames in the wing tanks shall be able to withstand the hatchcover reaction forces specified by the hatch cover maker

h) any transverse bulkhead in the cargo hold region shall be capable of withstanding MH from one side, atscantling draught TSC

i) the longitudinal bulkhead in way of the empty holds shall be strengthened for empty hold, with emptywing tank across, at the lightest ballast draught TLB

j) any fuel oil tank being 100% full, with adjacent tank, if any, being empty, at the lightest ballast draughtTLB.

4.2.2 Required harbour loading patterns depending on guidance for loading/unloading sequencesThe following loading patterns shall be applied depending on information given in the guidance for theloading/unloading sequences:

a) any cargo hold carrying MH, with all double bottom fuel oil tanks in way of the cargo hold, if any, being100% full, at the lightest draught given in the loading/unloading sequences TS,MIN,FULL,HAR

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b) any cargo hold taken empty, with all double bottom tanks in way of the cargo hold, if any, being empty,at the deepest draught given in the loading/unloading sequences TS,MAX,EMPTY,HAR

c) any two adjacent cargo holds carrying MH, with the next holds being empty, with all double bottom fueloil tanks in way of the adjacent cargo holds, if any, being 100% full, at the lightest draught given in theloading/unloading sequences TADJ,MIN,FULL,HAR

d) any two adjacent cargo holds being empty with the next holds being full, with all double bottom tanksin way of the adjacent cargo holds, if any, being empty, at the deepest draught given in the loading/unloading sequences TADJ,MAX,EMPTY,HAR

e) in the guidance for the loading/unloading sequences, a minimum required amount of ballast in the wingtank shall be considered when the adjacent cargo hold is empty:

— if the loading/unloading sequences show that the unloading sequence from commencement of cargodischarge to completion is time-wise synchronized with the ballasting operation, empty hold with finalballast filling level for the wing tank across will be considered

— If the ballasting operation is not synchronized with the cargo discharge, the longitudinal bulkheadshall be strengthened for a minimum amount of ballast in the wing tank when the adjacent cargo holdis empty. If such a minimum amount of ballast is not given in the guidance for the loading/unloadingsequences, the longitudinal bulkhead shall be strengthened for empty cargo hold at the deepestdraught given in the loading/unloading sequences TS,MAX,EMPTY,HAR, with wing tank empty across.

f) ore carriers having a deadweight capacity above 200 000 DWT shall be capable of being loaded to thefull deadweight capacity using one pour per hold.

4.2.3 Required loading patterns depending on loading manualThe following loading patterns shall be considered depending on information given in the loading manual:

a) watertight transverse bulkheads within the cargo hold region shall be capable of withstanding flooding ofsea water up to the freeboard deck at side

b) if water ballast is exchanged by sequential method, the longitudinal bulkhead shall be capable ofhaving empty wing tank and empty cargo hold across at the deepest draught given in the ballast waterexchange manual

c) unsymmetrical loading conditions, if included in the loading manual or in the ballast water exchangemanual, shall be specially considered

d) for seagoing loading conditions involving partially filled wing water ballast tanks, the primary supportingmembers shall be strengthened for filling levels empty and 100% full.

4.2.4 Multiport seagoing conditionsThe following alternate conditions are applicable to OC(M) only:

a) specified holds carrying MH, with all double bottom fuel oil tanks in way of the cargo hold, if any, being100% full, at the lightest draught given in the loading manual TS,MIN,ALT,SEA

b) specified holds taken empty, with all double bottom tanks in way of the cargo hold, if any, being empty,at the deepest draught given in the loading manual TS,MAX,ALT,SEA

c) the longitudinal bulkhead in way of the empty holds shall be strengthened for empty hold with emptywing tank across, at the deepest draught given in the loading manual TS,MAX,ALT,SEA

d) the double bottom in way of the empty holds shall be strengthened for empty hold with full wing tankacross, at the deepest draught given in the loading manual TS,MAX,ALT,SEA.

4.2.5 Assumptions with respect to structural arrangement for the provided standard design loadcombinationsThe standard design load combinations given in [4.2.8] and the standard loading conditions for fatigueassessment given in [4.3.1] are based on the following assumptions with respect to structural arrangements:

— within the midship region partial transverse bulkheads are fitted in the double side separating wing waterballast tanks and void spaces

— fuel oil tanks are fitted in the double side in way of the aftmost cargo hold.

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4.2.6 Assumptions with respect to tank fillings depending on loading manual and guidance forloading/unloading sequencesThe standard design load combinations given in [4.2.8] are further based on the following assumptions withrespect to tank fillings applied to the loading conditions included in the loading manual and in the guidancefor loading/unloading sequences:

— in order to avoid excessive forward trim when consuming fuel oil, the wing water ballast tank in way ofthe aftmost cargo hold are being partially filled. Departure conditions (with 100% full fuel oil tanks andempty wing water ballast tanks), and arrival conditions (with empty fuel oil tanks and 100% full wingwater ballast tanks) are shown in Table 10

— for harbour conditions representing the guidance for loading/unloading sequences, it is assumed thatcargo loading/unloading is time-wise synchronized with ballasting/de-ballasting of wing water ballasttanks adjacent to cargo holds being loaded/unloaded.

4.2.7 Limitations to the standard design load combinationsIf the assumptions given in [4.2.5] and [4.2.6] are not complied with the standard design load combinationsshall be adjusted accordingly.Effects on the longitudinal shear strength and the girder strength due to asymmetrical loading during ballastwater exchange conditions shall be specially considered, where relevant. Additional design load combinationsshall then be defined with target hull girder shear adjusted to 100% of permissible limit in way of transversebulkheads.

4.2.8 Standard design load combinations for cargo hold FE analysisThe hold mass curves given in [5] shall form the basis for the design load combinations for direct strengthanalysis.In the following tables for the standard design load combinations, references to the required loading patternsin accordance with [4.2.1] to [4.2.4] are given for each design load combination. The standard design loadcombinations for FE analysis are given as follows, see Table 6:

Table 6 Standard FE design load combination tables OC ships

Midship cargohold region Aftmost cargo hold Foremost cargo hold

OC(H) and OC(M) Table 7 Table 10 Table 13

OC(M) – EA Table 8 Table 11 Table 14

OC(M) – FA Table 9 Table 12 Table 15



The fraction of permissible still water bending moment (SWBM) for each design load combination representsminimum required. If a loading condition with same loading pattern is given in the loading manual or in theloading/unloading sequences having a greater fraction of SWBM, the value given in the loading informationshall be applied as target.


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Table 7 FE Load combinations - Midship cargo hold region

No. Description Req. ref Loading pattern Draught% ofperm.SWBM

% ofperm.SWSF

Dynamicload case

Seagoing conditions

0% ≤100%

BSR-1P/S

OST-2P/S

OSA-1P/S

1 1)

Full loadcondition [4.1.2]

Hold full [4.2.1] item a

Adj, holds full[4.2.1] item c

WBT empty[4.2.1] item f

TSC

100%(sag.) ≤100%

BSP-1P/S

BSR-1P/S

OST-1P/S

OSA-2P/S

0% ≤100%FSM-2

HSM-2

2 1)

Full loadcondition [4.1.2]


Adj, holds full[4.2.1] item c

WBT empty[4.2.1] item f

HC reaction forces[4.2.1] item g

TSC100%(sag.) ≤100%

FSM-1

HSM-1

HSA-1


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% ofperm.SWSF

Dynamicload case

3

Heavy ballastcondition [4.1.5]

Hold empty[4.2.1] item b

Adj, holds empty[4.2.1] item d

THB100%(hog.) ≤100%

FSM-2

HSM-2

BSR-1P/S

OST-2P/S

OSA-1P/S

100% 7)

Max SFLCFSM-2

HSM-2

100% 8)

Max SFLCFSM-2

HSM-2100%(hog.)

≤100%

FSM-2

HSM-2

BSR-1P/S

OST-2P/S

OSA-1P/S

≤100%

HSA-1

BSP-1P/S

BSR-1P/S

OSA-2P/S

4Light ballast

condition [4.1.4]

WBT full [4.2.1] item e

TLB

50%(sag.)

100% 9)

Max SFLCFSM-1

HSM-1


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% ofperm.SWSF

Dynamicload case

100% 7)

Max SFLCFSM-2

HSM-2

100% 8)

Max SFLCFSM-2

HSM-2100%(hog.)

≤100%

FSM-2

HSM-2

BSR-1P/S

OST-2P/S

OSA-1P/S

≤100%

HSA-1

BSP-1P/S

BSR-1P/S

OSA-2P/S

5

Light ballastcondition [4.1.4]

WBT and holdempty [4.2.1] item i

TLB

50%(sag.)

100% 9)

Max SFLCFSM-1

HSM-1

0% ≤100% OSA-1P/S

6 2) TBHD [4.2.1] item h

TSC 100%(sag.) ≤100%

HSA-1

BSP-1P/S

BSR-1P/S

OSA-2P/S


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% ofperm.SWSF

Dynamicload case

100% 7)

Max SFLCFSM-2

HSM-2100%(hog.) 100% 8)

Max SFLCFSM-2

HSM-2

7 3)

BWM-E(s)[4.2.3] item b

Unsymmetricalloading [4.2.3] item c

T MAX,E

MPT

Y,W

BE

50%(sag.)

100% 9)

Max SFLCFSM-1

HSM-1

Harbour conditions

100% 5)

Max SFLC N/A50%

(hog.) 100% 6)

Max SFLC N/A

100% 5)

Max SFLC N/A

100% 6)

Max SFLC N/A

8 1) Hold full [4.2.2] item a

T S,M

IN,F

ULL

,HAR

100%(sag.)

≤100% N/A

100% 5)

Max SFLC N/A

100% 6)

Max SFLC N/A100%(hog.)

≤100% N/A

100% 5)

Max SFLC N/A

9 1)

Hold empty[4.2.2] item b

Min WB across[4.2.2] item e

T S

,MAX,E

MPT

Y,H

AR

50%(sag.) 100% 6)

Max SFLC N/A


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% ofperm.SWSF

Dynamicload case

50%(hog.) ≤100% N/A

10 1)

T AD

J,M

IN,F

ULL

,HAR

100%(sag.) ≤100% N/A

50%(hog.) ≤100% N/A

11 1)

Adj. hold full[4.2.2] item c

T AD

J,M

IN,F

ULL

,HAR

100%(sag.) ≤100% N/A

100%(hog.) ≤100% N/A

12 1)

Adj. hold empty[4.2.2] item d

Min WB across[4.2.2] item e

T A

DJ,

MAX,E

MPT

Y,H

AR

50%(sag.) ≤100% N/A


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% ofperm.SWSF

Dynamicload case

100%(hog.) ≤100% N/A

13 1)

T AD

J,M

AX,E

MPT

Y,H

AR

50%(sag.) ≤100% N/A

Flooded conditions

14 4) Hold flooded[4.2.3] item a

TDAM100%(sag.) ≤100% N/A

1) Maximum cargo density shall be used for calculation of dry cargo pressure.2) Cargo assumed filled up to top of hatch coaming shall be used for calculation of dry cargo pressure.3) Load case only relevant if ballast is exchanged by means of sequential method.4) Load case only relevant if the transverse bulkhead is defined as watertight according to the damage control plan.5) The shear force shall be adjusted to target value at aft bulkhead of the mid-hold.6) The shear force shall be adjusted to target value at forward bulkhead of the mid-hold.7) For the mid-hold where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at aft bulkhead of the mid-hold.8) For the mid-hold where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at forward bulkhead of the mid-hold.9) This load combination shall be considered only for the mid-hold, where xb-aft>0.5L or xb-fwd<0.5L


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Table 8 Additional FE Load combinations applicable to empty hold in alternate condition (EA) of OC(M) - Midship cargohold region


% ofperm.SWSF

Dynamicload case

Seagoing conditions

100% 2)

Max SFLCFSM-2

HSM-2

100% 3)

Max SFLCFSM-2

HSM-2100%(hog.)

≤100%

FSM-2

HSM-2

BSR-1P/S

OST-2P/S

OSA-1P/S

≤100%BSP-1P/S

BSR-1P/S

15 1)

Alternate load condition[4.1.3]

Hold empty [4.2.4] itemb

Empty WB across [4.2.4]item c

T S,M

AX,A

LT,S

EA

50%(sag.) 100% 4)

Max SFLCFSM-1

HSM-1

16 1)

Alternate load condition[4.1.3]

Hold empty [4.2.4] itemb

Full WB across [4.2.4]item d

T S,M

AX,A

LT,S

EA

100%(hog.) ≤100%

FSM-2

HSM-2

BSR-1P/S

OST-2P/S

OSA-1P/S

1) Maximum cargo density shall be used for calculation of dry cargo pressure.2) For the mid-hold where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at aft bulkhead of the mid-hold.3) For the mid-hold, where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at forward bulkhead of the mid-hold.4) This load combination shall be considered only for the mid-hold, where xb-aft>0.5L or xb-fwd<0.5L.


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Table 9 Additional FE Load combinations applicable to loaded hold in alternate condition (FA) of OC(M) - Midship cargohold region


% ofperm.SWSF

Dynamicload case

Seagoing conditions

100% 4)

Max SFLCFSM-2

HSM-250%(hog.)

≤100% OSA-1P/S

100% 2)

Max SFLCFSM-1

HSM-1

100% 3)

Max SFLCFSM-1

HSM-1

15 1)Alternate load condition[4.1.3]


T S,M

IN,A

LT,S

EA

100%(sag.)

≤100%

HSA-1

BSP-1P/S

BSR-1P/S

OSA-2P/S

1) Maximum cargo density shall be used for calculation of dry cargo pressure.2) For the mid-hold where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at aft bulkhead of the mid-hold.3) For the mid-hold, where xb-aft<0.5L and xb-fwd>0.5L, the shear force shall be adjusted to target value at forward bulkhead of the mid-hold.4) This load combination shall be considered only for the mid-hold, where xb-aft>0.5L or xb-fwd<0.5L.

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Table 10 FE Load combinations - Aftmost cargo hold


% ofperm.SWSF

Dynamicload case

Seagoing conditions

0% ≤100%

OST-2P/S

OSA-1P/S

BSR-1P/S

1a 1)

TSC

100%(sag.) ≤100%

BSP-1P/S

BSR-1P/S

OST-1P/S

0% ≤100%

OST-2P/S

OSA-1P/S

BSR-1P/S

1b 1)

Full load condition [4.1.2]


Adj, holds full [4.2.1] item c

WBT empty [4.2.1]item f

Part. filled WBT [4.2.3] item d

TSC

100%(sag.) ≤100%

BSP-1P/S

BSR-1P/S

OST-1P/S

0% ≤100%

FSM-2

HSM-2

HSA-2

2a 1)




WBT empty [4.2.1] item f


HC reaction forces [4.2.1] item g

TSC

100%(sag.)

100%Max SFLC

FSM-1

HSM-1

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0% ≤100%

FSM-2

HSM-2

HSA-2

2b 1)

TSC

100%(sag.)

100%Max SFLC

FSM-1

HSM-1

3a

THB100%(hog.) ≤100%

FSM-2

HSM-2

BSR-1P/S

OSA-1P/S

3b

Heavy ballast condition [4.1.5]

Hold empty [4.2.1] item b

Adj, holds empty [4.2.1] item d


THB100%(hog.) ≤100%

FSM-2

HSM-2

BSR-1P/S

OSA-1P/S

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100% 7)

Max SFLCFSM-2

HSM-2100%(hog.)

≤100%

HSA-2

BSR-1P/S

OSA-1P/S

100% 7)

Max SFLCFSM-1

HSM-1

4

Light ballast condition [4.1.4]



TLB

0%

≤100%BSP-1P/S

BSR-1P/S

100% 7)

Max SFLCFSM-2

HSM-2100%(hog.)

≤100%

HSA-2

BSR-1P/S

OSA-1P/S

100% 7)

Max SFLCFSM-1

HSM-1

5


WBT empty [4.2.1] item i


TLB

0%

≤100%BSP-1P/S

BSR-1P/S

0% ≤100%HSA-2

OSA-1P/S

6 2) TBHD [4.2.1] item h

TSC100%(sag.) ≤100%

BSP-1P/S

BSR-1P/S

100%(hog.)

100% 7)

Max SFLCFSM-2

HSM-2

7 3)BWM-E(s) [4.2.3] item b


T MAX,E

MPT

Y,W

BE

0%100% 7)

Max SFLCFSM-1

HSM-1

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100%(hog.) ≤100%

HSA-2

OSA-1P/S

8a

TLB

0% ≤100%BSP-1P/S

BSR-1P/S

100%(hog.) ≤100%

HSA-2

OSA-1P/S

8b

FO strength [4.2.1] item j

TLB

0% ≤100%BSP-1P/S

BSR-1P/S

Harbour conditions

100% 5)

Max SFLC N/A50%

(hog.) 100% 6)

Max SFLC N/A

100% 5)

Max SFLC N/A9 1) Hold full [4.2.2] item a

T S,M

IN,F

ULL

,HAR

100%(sag.) 100% 6)

Max SFLC N/A

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100% 5)

Max SFLC N/A100%(hog.) 100% 6)

Max SFLC N/A

100% 5)

Max SFLC N/A10 1) Hold empty [4.2.2] item b

Min WB across [4.2.2] item e

T S,M

AX,E

MPT

Y,H

AR

50%(sag.) 100% 6)

Max SFLC N/A

50%(hog.) ≤100% N/A

11 1) Adj. hold full [4.2.2] item c

T A

DJ,

MIN

,FU

LL,H

AR

100%(sag.) ≤100% N/A

100%(hog.) ≤100% N/A

12Adj. hold empty [4.2.2] item d


T AD

J,M

AX,E

MPT

Y,H

AR

50%(sag.) ≤100% N/A

Flooded conditions

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13 4) Hold flooded [4.2.3] item a

TDAM100%(sag.) ≤100% N/A

14 4) ER flooded [4.2.3] item a

TDAM100%(hog.) ≤100% N/A

1) Maximum cargo density shall be used for calculation of dry cargo pressure.2) Cargo assumed filled up to top of hatch coaming shall be used for calculation of dry cargo pressure.3) Load case only relevant if ballast is exchanged by means of sequential method.4) Only transverse bulkheads defined as watertight according to the damage control plan to be evaluated.5) The shear force shall be adjusted to target value at engine room bulkhead.6) The shear force shall be adjusted to target value at forward bulkhead.7) If method 1 (M1) given in DNVGL-CG-127, Finite element analysis, [3.6.3.5] result in total vertical shear force

exceeding the total vertical hull girder shear capacity at mid hold length, method 2 (M2) should be applied.

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Table 11 Additional FE Load combinations applicable to empty hold in alternate condition (EA) ofOC(M) - Aftmost cargo hold


% ofperm.SWSF

Dynamicload case

Seagoing conditions

100%2)

Max SFLCFSM-2

HSM-250%(hog.)

≤100%BSR-1P/S

OSA-1P/S

100%2)

Max SFLCFSM-1

HSM-115 1)

Alternate load condition [4.1.3]


Empty WB across [4.2.4] item c


T S,M

AX,A

LT,S

EA

0%

≤100%BSP-1P/S

BSR-1P/S

16 1)



Full WB across [4.2.4] item d


T S,M

AX,A

LT,S

EA

50%(hog.) ≤100%

FSM-2

HSM-2

BSR-1P/S

OSA-1P/S

1) Maximum cargo density shall be used for calculation of dry cargo pressure.2) If method 1 (M1) given in DNVGL-CG-127, Finite element analysis, [3.6.3.5] result in total vertical shear force

exceeding the total vertical hull girder shear capacity at mid hold length, method 2 (M2) should be applied.

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Table 12 Additional FE Load combinations applicable to loaded hold in alternate condition (FA) ofOC(M) - Aftmost cargo hold


% ofperm.SWSF

Dynamicload case

Seagoing conditions

100%Max SFLC

FSM-2

HSM-20%

≤100%HSA-2

OSA-1P/S

100%Max SFLC

FSM-1

HSM-115 1)




T S,M

IN,A

LT,S

EA

50%(sag.)

≤100%BSP-1P/S

BSR-1P/S

1) Maximum cargo density shall be used for calculation of dry cargo pressure.

Table 13 FE Load combinations - Foremost cargo hold


% ofperm.SWSF

Dynamicload case

Seagoing conditions

0% ≤100%BSR-1P/S

OST-2P/S

1 1)





TSC100%(sag.) ≤100%

BSP-1P/S

BSR-1P/S

OST-1P/S

OSA-2P/S

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% ofperm.SWSF

Dynamicload case

0% ≤100%FSM-2

HSM-2

≤100% HSA-1

2 1)





HC reaction forces [4.2.1] item g

TSC100%(sag.) 100%

Max SFLCFSM-1

HSM-1

3

Heavy ballast condition [4.1.5]


Adj, holds empty [4.2.1] item d

THB100%(hog.) ≤100%

FSM-2

HSM-2

BSR-1P/S

OST-2P/S

100%Max SFLC

FSM-2

HSM-2100%(hog.)

≤100%BSR-1P/S

OST-2P/S

100%Max SFLC

FSM-1

HSM-14



TLB

0%

≤100%

HSA-1

BSP-1P/S

BSR-1P/S

OSA-2P/S

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% ofperm.SWSF

Dynamicload case

100%Max SFLC

FSM-2

HSM-2100%(hog.)

≤100%BSR-1P/S

OST-2P/S

5Light ballast condition [4.1.4]

WBT empty [4.2.1] item i

TLB

0%100%

Max SFLCFSM-1

HSM-1

6 2) TBHD [4.2.1] item h

TSC100%(sag.) ≤100%

HSA-1

BSP-1P/S

BSR-1P/S

OSA-2P/S

100%(hog.)

100%Max SFLC

FSM-2

HSM-2

7 3)BWM-E(s) [4.2.3] item b


T MAX,E

MPT

Y,W

BE

0%100%

Max SFLCFSM-1

HSM-1

Harbour conditions

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% ofperm.SWSF

Dynamicload case

100% 5)

Max SFLC N/A50%

(hog.) 100% 6)

Max SFLC N/A

100% 5)

Max SFLC N/A8 1) Hold full [4.2.2] item a

T S,M

IN,F

ULL

,HAR

100%(sag.) 100% 6)

Max SFLC N/A

100% 5)

Max SFLC N/A100%(hog.) 100% 6)

Max SFLC N/A

100% 5)

Max SFLC N/A9 1) Hold empty [4.2.2] item b


T S,M

AX,E

MPT

Y,H

AR

50%(sag.) 100% 6)

Max SFLC N/A

50%(hog.) ≤100% N/A

10 1) Adj. hold full [4.2.2] item c

T AD

J,M

IN,F

ULL

,HAR

100%(sag.) ≤100% N/A

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% ofperm.SWSF

Dynamicload case

100%(hog.) 100% N/A

11Adj. hold empty [4.2.2] item d


T AD

J,M

AX,E

MPT

Y,H

AR

50%(sag.) ≤100% N/A

Flooded conditions

12 4) Hold flooded [4.2.3] item a

TDAM100%(sag.) ≤100% N/A

13 4) FP flooded [4.2.3] item a

TDAM100%(sag.) ≤100% N/A

1) Maximum cargo density shall be used for calculation of dry cargo pressure.2) Cargo assumed filled up to top of hatch coaming shall be used for calculation of dry cargo pressure.3) Load case only relevant if ballast is exchanged by means of sequential method.4) Only transverse bulkheads defined as watertight according to the damage control plan to be evaluated.5) The shear force shall be adjusted to target value at aft bulkhead.6) The shear force shall be adjusted to target value at fore peak bulkhead.

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Table 14 Additional FE Load combinations applicable to empty hold in alternate condition (EA) ofOC(M) - Foremost cargo hold

No. Description Req. ref Loading pattern Draught % of perm.SWBM

% ofperm.SWSF

Dynamicload case

Seagoing conditions

100%Max SFLC

FSM-2

HSM-250% (hog.)

≤100%BSR-1P/S

OST-2P/S

100%Max SFLC

FSM-1

HSM-114 1)



Empty WB across [4.2.4] item c

T S,M

AX,A

LT,S

EA

0%

≤100%

BSP-1P/S

BSR-1P/S

OSA-2P/S

15 1)Alternate load condition [4.1.3]


Full WB across [4.2.4] item d

T S,M

AX,A

LT,S

EA

50% (hog.) ≤100%

BSR-1P/S

FSM-2

HSM-2

OST-2P/S


Table 15 Additional FE Load combinations applicable to loaded hold in alternate condition (FA) ofOC(M) - Foremost cargo hold


% of perm.SWSF

Dynamicload case

Seagoing conditions

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% of perm.SWSF

Dynamicload case

0%100%

Max SFLCFSM-2

HSM-2

100%Max SFLC

FSM-1

HSM-1

14 1) Alternate load condition [4.1.3]


T S,M

IN,A

LT,S

EA

50% (sag.)

≤100%

HSA-1

BSP-1P/S

BSR-1P/S

OSA-2P/S


4.3 Standard loading conditions for fatigue assessment

4.3.1 Standard loading conditions to be applied to ore carriers for fatigue assessment are give in Table 16.Guidance note:Further explanations of the columns in Table 16 are given in DNVGL-CG-0127, Finite element analysis, [3.4.4].



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Table 16 FE Load combinations - Midship cargo hold region


% ofperm.SWSF

Dynamicload case

Seagoing conditions

1-F 1) Full load homogeneous

TSC100%(sag.) NA All


TBAL50%(sag.) ≤100% All

1) The actual shear force curve that results from the application of static and dynamic loads to the FE model shall be used.2) The actual shear force curve that results from the application of static and dynamic loads to the FE model shall be used. Where this shear force

exceeds the target value, the correction of vertical loads shall be applied to adjust the shear force down to the target value.

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5 Hold mass curves

5.1 Introduction5.1.1 ScopeThis sub-section describes the procedure to be used for determination of:

— the maximum and minimum mass of cargo in each cargo hold as a function of the draught at mid-holdposition of cargo hold

— the maximum and minimum mass of cargo in any two adjacent holds as a function of the draught at mid-length of these two adjacent cargo holds.

5.1.2 Relations with the design loading criteriaThe maximum allowable or minimum required cargo mass in a cargo hold, or in two adjacent loaded holdsis related to the net load on the double bottom. The net load on the double bottom is a function of draught,cargo mass in the cargo hold, as well as the mass of fuel oil and ballast water contained in double bottomtanks, if any.Based on the design loading criteria, as given in [4.2.1] to [4.2.4], hold mass curves for each single hold, aswell as for any two adjacent holds shall be included in the loading manual and the loading instrument.The allowable loading represented by the hold mass curves shall envelope all seagoing loading conditions andall loading/unloading sequences.

Guidance note:For the hold mass curves, MH and the draughts in way of the knuckle points will be applied as design basis in the design loadcombinations for direct strength analysis in [4.2.8]. It is therefore recommended that, for initial design, the following margins areapplied when establishing the hold mass curves:

— MH from the provided preliminary loading information should be increased by 2% and rounded up to closest 100 t

— the draughts from the provided preliminary loading information, representing the knuckle points of the maximum hold masscurves, should be reduced by 200 mm and rounded down to the closest 100 mm

— the draughts from the provided preliminary loading information, representing the knuckle points of the minimum hold masscurves, should be increased by 200 mm and rounded up to the closest 100 mm.


5.1.3 Hold mass curves within the midship cargo hold regionThe validity of hold mass curves for every single cargo hold and every two adjacent holds within the midshipregion shall be confirmed by FE cargo hold analysis in accordance with [7.1]. All holds within the midshipregion having same volume and shape shall be represented by the same hold mass curves, unless FE cargohold analysis in accordance with [7.1] is carried out for such holds.

5.1.4 Cargo holds outside midship region not covered by FE cargo hold modelCargo holds outside the midship region not covered by a cargo hold model in accordance with [7.1], havingsame volume and shape as for the cargo holds within the midship region, shall not have hold mass curvesthat are exceeding the allowable loading established for the cargo holds within the midship region.

Guidance note:In such case the hold mass curves being representative for the cargo holds within the midship region may have to be adjusted inorder to envelope the loading information for similar holds outside the midship region.


5.1.5 Maximum and minimum permissible mass expressionThe maximum and minimum permissible mass in seagoing conditions, (WmaxS(T), WminS(T)) and in harbourcondition ((WmaxH(T), WminH(T)) at various draughts (T) is obtained, in t, by the following formulae given intables of [5.2] and [5.3] for the following:

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— OC(H) ships— OC(M) ships.

5.2 Single cargo hold5.2.1 OC(H) shipsMaximum permissible mass and minimum required mass of single cargo hold of OC(H) ships are shown inTable 17.

Table 17 OC(H) ships


Maximum:

I [4.2.1] a

SeagoingMinimum:

II

[4.2.1] b

Maximum:

III

[4.2.2] a

HarbourMinimum:

IV [4.2.2] b

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5.2.2 OC(M) shipsMaximum permissible mass and minimum required mass of single cargo hold of OC(M) ships are shown inTable 18.

Table 18 OC(M) ships


Ref Ref

Maximum:

I [4.2.4] a

FA SeagoingMinimum:

II

[4.2.1] b

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Ref Ref

Maximum:

III [4.2.2] a

HarbourMinimum:

IV [4.2.2] b

EA Seagoing

Maximum

I [4.2.4] b

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Ref Ref

Minimum:

II [4.2.1] b

Maximum:

III [4.2.2] a

HarbourMinimum:

IV [4.2.2] b

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5.3 Two adjacent holds5.3.1 OC(H) and OC(M) shipsMaximum permissible mass and minimum required mass of two adjacent holds of OC(H) and OC(M) shipsare shown in Table 19.

Table 19 OC(H) and OC(M) ships


Ref Ref

Maximum:

I [4.2.1] c

SeagoingMinimum:

II [4.2.1] d

Maximum:

III [4.2.2] c

HarbourMinimum:

IV [4.2.2] d

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Ref Ref

6 Hull local scantling

6.1 Plating6.1.1 Plating subject to lateral pressureThe requirements given in Pt.3 Ch.6 Sec.4 [1] shall be complied with, applying the additional design loadsets given in Pt.5 Ch.1 Sec.2 [5.1], with mass and density in accordance with [3.2].

6.2 Stiffeners6.2.1 Stiffeners subject to lateral pressureThe requirements given in Pt.3 Ch.6 Sec.5 [1] shall be complied with, applying the additional design loadsets given in Pt.5 Ch.1 Sec.2 [5.1], with mass and density in accordance with [3.2].

6.3 Intersection of stiffeners and primary supporting members6.3.1 Connection of stiffeners to primary supporting membersThe requirements for connection of stiffeners to primary supporting members shall comply with Pt.3 Ch.6Sec.7 [1] with internal pressures due to dry bulk cargo in accordance with Pt.5 Ch.1 Sec.2 [3], applyingcargo mass and density given in [3.2].

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7 Finite element analysis

7.1 Cargo hold analysis7.1.1 GeneralCargo hold analysis shall be carried out in accordance with Pt.5 Ch.1 Sec.7 [7.1] using detailed requirementsgiven in the following sub-sections.

7.1.2 ApplicationCargo hold analysis by use of finite element analysis is mandatory for:

— midship region— foremost cargo hold— aftmost cargo hold.

For ore carriers having different wing tank configuration between cargo hold transverse bulkheads within themidship region, such as additional partial transverse bulkheads fitted separating wing water ballast tanks andwing void spaces, minimum two midship cargo hold models are mandatory.

7.1.3 Selection of cargo hold model(s) within the midship regionCargo hold model(s) within the midship region shall be selected such that the transverse section at atransverse bulkhead with the maximum hull girder forces (still water and wave) will be assessed.

Guidance note:Ballast loading conditions with full wing ballast tanks within the mid hold length only and all cargo holds empty will induce a hullgirder shear force correction, increasing the hull girder shear force for the ship’s side in way of the transverse bulkheads. Designload sets with such filling and hull girder shear forces adjusted to permissible limits in way of transverse bulkheads will give asufficient verification of ship’s side shear force strength in way of transverse bulkheads, including shear force correction due to unevendistribution of vertical loads.


7.1.4 Primary supporting members outside midship region not covered by FE cargo hold modelFor primary supporting members for cargo holds outside the midship region, with structural arrangementsand hold mass curves as for the midship cargo region, the net scantlings of such primary strength membersshall not be less than those required for the cargo holds within the midship region, with due attention toreduction in longitudinal stress.


7.1.6 Internal loadsBulk pressures and shear loads in accordance with Pt.5 Ch.1 Sec.2 [3], with mass and density in accordancewith [3.2], shall be applied to the FE models.

7.1.7 Evaluation of transverse bulkheads subject to dry bulk and flooded pressuresFor design load combinations intended only for strength evaluation of transverse bulkheads due to dry bulkpressures as required in [4.2.1] item h) and, where applicable, for flooded scenarios as required in [4.2.3]item a), the evaluation areas are limited to:

— for corrugated transverse bulkheads: corrugations, including upper stool and lower stool— for plane transverse bulkheads: primary supporting members in way of the transverse bulkhead.

7.1.8 Evaluation of FO tank bulkheadsFor design load combinations intended only for strength evaluation of fuel oil tank bulkheads as required in[4.2.1] item j), the evaluation areas are limited to the primary supporting members in way of the FO tankboundaries.

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7.1.9 Extended evaluation areas of foremost cargo hold modelProvided that the complete fore peak is modelled with actual hull shape and representative layout of primarysupporting members, the foremost cargo hold model may be used for compliance with the requirementsgiven in Pt.5 Ch.1 Sec.7 [6.4.2].If scantlings of all primary supporting members within the fore peak are based on the foremost cargo holdmodel the requirements given in Pt.5 Ch.1 Sec.7 [3.3.1] to Pt.5 Ch.1 Sec.7 [3.3.4], Pt.5 Ch.1 Sec.7 [6.1.1]and Pt.5 Ch.1 Sec.7 [6.3.2] can be disregarded.Required design load combinations intended for strength evaluation of the fore peak are limited to the fullload condition, 2 given in Table 13, combined with Equivalent Design Waves FSM-1, HSM-1 and HSA-1.

Guidance note:The boundary constrains at the fore end of the model should be applied to the foremost web frame of the fore peak, with evaluationarea limited to between the collision bulkhead and the web frame adjacent to the foremost web frame.


The requirement given in Pt.5 Ch.1 Sec.7 [3.3.5] can be disregarded provided that it is demonstrated thatthe chain locker support has sufficient strength.

Guidance note:An acceptable method to the Society to demonstrate sufficient strength of the chain locker support would be applying the weight ofthe chain cable as uniform distributed load on the bottom of the chain locker, combined with Equivalent Design Wave HSA-1.


7.1.10 Extended evaluation areas of aftmost cargo hold modelProvided that the complete machinery space is modelled with actual hull shape and representative layoutof primary supporting members, the aftmost cargo hold model may be used for compliance with therequirements given in Pt.5 Ch.1 Sec.7 [6.4.3].If scantlings of all primary supporting members within the machinery space are based on the aftmost cargohold model the requirements given in Pt.5 Ch.1 Sec.7 [3.4.1] to Pt.5 Ch.1 Sec.7 [3.4.3], Pt.5 Ch.1 Sec.7[6.1.2] and Pt.5 Ch.1 Sec.7 [6.3.3] can be disregarded.Required design load combinations intended for strength evaluation of the machinery space are limited to thefull load condition with fuel oil tanks full, 2a given in Table 10, combined with Equivalent Design Waves FSM-1and HSM-1.

Guidance note:The boundary constrains at the aft end of the model should be applied to the engine room aft bulkhead, with evaluation area limitedto between the web frame adjacent to the engine room aft bulkhead and the engine room front bulkhead.


7.2 Local structural strength analysis7.2.1 GeneralLocal structural strength analysis shall be carried out in accordance with Pt.3 Ch.7 Sec.4 using detailedrequirements given in the following sub-sections.

Guidance note:Calculation methods acceptable to the Society are further outlined in the Society's document DNVGL-CG-0127 Finite element analysis.


7.2.2 ApplicationLocal structural strength analysis by use of finite element analysis shall be carried out within the midshipregion for the following members:

— one longitudinal section within the cargo hold with connections between inner bottom and bottomlongitudinal stiffeners, and adjoining structures of transverse bulkhead, subject to maximum relativedisplacement between supports

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— one longitudinal section within the wing tank with connections between deck and bottom longitudinalstiffeners and adjoining structures of transverse bulkhead, subject to maximum relative displacementbetween supports.


7.2.4 Internal loadsBulk pressures and shear loads in accordance with Pt.5 Ch.1 Sec.2 [3], with mass and density in accordancewith [3.2], shall be applied to the FE models.

8 Buckling

8.1 Hull girder bucklingThe requirements given in Pt.5 Ch.1 Sec.7 [8.1] shall be complied with, applying the additional design loadsets given in Pt.5 Ch.1 Sec.2 [5.1], with mass and density in accordance with [3.2].

9 Fatigue

9.1 Fatigue strength calculations9.1.1 GeneralFatigue assessment shall be carried out in accordance with Pt.3 Ch.9 using detailed requirements in thefollowing sub-sections.

Guidance note:Calculation methods acceptable to the Society are further outlined in the Society's document DNVGL-CG-0129 Fatigue assessmentof ship structure.


9.2 Prescriptive fatigue strength assessment9.2.1 GeneralWithin the cargo region, the fatigue life of longitudinal end connections in way of web frames and transversebulkheads shall be assessed in accordance with the Society's document DNVGL-CG-0129 Fatigue assessmentof ship structure. The following stress components shall be considered in the fatigue assessment:

— DNVGL-CG-0129 [4.4]: stress due to global hull girder stress— DNVGL-CG-0129 [4.6]: local stiffener bending stress— Local relative deflection stress in accordance with [8.2.2].

9.2.2 Local relative deflection stressThe effect of relative deflection of stiffener end connections in way of transverse bulkhead within the midshipregion shall be taken into account in the fatigue strength assessment according to the Society's documentDNVGL-CG-0129 Fatigue assessment of ship structure, [4.7].Standard fatigue loading conditions as given in [4.3.1] shall be applied to the midship FE cargo hold model.

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9.3 Finite element stress analysis9.3.1 Application and scopeWithin the midship region, the connection between the inner bottom and the longitudinal bulkhead or hopperplating in way of floors, being a web-stiffened cruciform joint, shall be assessed in accordance with theSociety's document DNVGL-CG-0129 Fatigue assessment of ship structure, [6.5.2].Standard fatigue loading conditions as given in [4.3.1] shall be applied to the stress concentration model.

10 Loading manual and loading instrument

10.1 Loading manualThe requirements given in Sec.4 [10.1] shall be complied with.

10.2 Loading instrumentThe requirements given in Sec.4 [10.2] shall be complied with.

10.3 Guidance for loading/unloading sequencesThe requirements given in Sec.4 [10.3] shall be complied with.

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SECTION 6 EXTENDED FATIGUE ANALYSIS OF SHIP DETAILS - PLUS

1 General

1.1 IntroductionAdditional class notationPlus specifies an extended scope of fatigue strength verification for hull structuraldetails. The Plus class notation will lower the probability of fatigue damage to hull structural details that arenot covered by main class requirements in combination with ship type requirements given in Pt.5, or CSR.

1.2 ScopeThe scope of additional class notation Plus is to add an increased level of safety related to additional fatiguestrength assessment of hull structural details. The additional fatigue strength assessment includes fatiguestrength calculations based on finite element analysis of selected fatigue critical details. The rules in thissection are considered to satisfy the requirements for fatigue strength assessment in addition to thosespecified in main class requirements in combination with ship type requirements given in Pt.5, or CSR. Anoverall description is given in Table 1:

Table 1 Calculation scope – Plus

Class notation Ultimate strength Fatigue strength locations Loads

Plus NA

— Longitudinal stiffener-frame connections to web stiffener, cut outand lug plate, see [3.3.2]

— Stringer heels and toes, see [3.3.2]— Bottom and side shell plating, see [3.3.2]— Strength deck plating in way of openings and attachments, see

[3.3.2]— For ships with internal structural members exposed to repeated

yielding, low cycle fatigue of locations given in [3.3.3]

Rule loads

1.3 Application1.3.1 Applicable ship typesThe additional class notationPlus is primarily intended for tankers and gas carriers of conventional design,but may also be applied to other types of vessels.

1.3.2 Plus in combination with CSAThe additional class notation Plus may be combined with the CSA notation, see Sec.7 [3.1.3].

1.4 Class notations1.4.1 PlusShips built in compliance with the requirements as specified in Table 2 may be assigned the additionalnotation related to structural strength and integrity as follows:

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Table 2 Additional class notation - Plus


Plus

Mandatory:

No


[3]

FiS requirements:

NA

<None> Extended scope of fatigue strength verification for hullstructural details


2 Documentation

2.1 Documentation requirements2.1.1 PlusDocumentation shall be submitted as required by Table 3.

Table 3 Documentation requirements - Plus


H080 – Strength analysis

Cargo hold FE models of aftmost hold, hold amidships andforemost hold, including:

— General information, see Pt.3 Ch.7 Sec.1 [4]— Detailed information, see DNVGL-CG-0127, Finite element

analysis, [1.2]

FI


Fine mesh FE models of typical frames in way of aftmost hold,hold amidships and foremost hold, including:

— General information, see Pt.3 Ch.7 Sec.1 [4]— Detailed information, see DNVGL-CG-0152, PLUS

FI


Very fine mesh FE models for details without tabulated stressconcentration factors, including:

— General information, see Pt.3 Ch.7 Sec.1 [4]— Detailed information, see DNVGL-CG-0129, Fatigue

assessment of ship structure, [6.3]

FI

Ship hullstructure

H085 – Fatigue analysis See DNVGL-CG-0152, PLUS, For more details FI

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H134 – Hole andpenetration plan

All holes and cut-outs in way of continuous members within thecargo hold region FI


For general requirements for documentation, including definition of the information codes, see Pt.1 Ch.3Sec.1.For a full definition of the documentation types, see Pt.1 Ch.3 Sec.3.


3.1 General3.1.1 Recognised computer programThe calculations required in the following sub-sections shall be carried out by computer programs supplied byor recognised by the Society. Recognised computer programs are programs applied by builders or designerswhere reliable results have been demonstrated to the satisfaction of the Society.

3.1.2 Minimum net scantlingsThe net scantlings shall not to be less than those determined by the main class requirements in combinationwith ship type requirements given in Pt.5, or CSR.

3.1.3 Hot spots covered by ship type requirements or CSRHot spots covered by the main class requirements in combination with ship type requirements given in Pt.5or CSR need not be recalculated according to the Plus requirements.

3.2 Finite element analysis3.2.1 Required structural modelsCharacteristics and application of different structural model types are given in Table 4.Cargo hold FE models shall be used to represent the overall stiffness of the primary supporting members.Fine mesh FE models shall be used to capture more local stress distributions in way of stiffener endconnections to web frames.The hot spot stresses are obtained either by use of tabulated stress concentration factors or very fine meshFE models.Fatigue pressure loads shall be applied to the structural models in accordance Pt.3 Ch.4 or CSR Pt.1 Ch.4.

Table 4 Required FE models - Plus

Model type Characteristics Application 4)

Cargo hold FEmodel 1)

— Three cargo hold length— stiffener spaced mesh (b x b)— May include fine mesh (50 mm x 50 mm)— May include very fine mesh (t × t)— Include local pressure loads and targeted global loads— Net scantlings (see Pt.3 Ch.3 Sec.2 or CSR Pt.1 Ch.3

Sec.2)

— Boundary conditions for sub-models— Screening of fatigue critical details— Reference stress for longitudinal

stiffener-frame connections subject toscreening

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Fine mesh FEmodel 2)

— Fine mesh (50 mm x 50 mm)— May include very fine mesh (t × t)— Sub-model— Longitudinal extent at least one frame spacing on each

side of the target frame— Include local pressure loads— Net scantlings (see Pt.3 Ch.3 Sec.2 or CSR Pt.1 Ch.3

Sec.2)

— Evaluate local geometric stress flowin way of stiffener end connections,including the effect of cut-outs andtripping brackets

— Establish scaling factor for screeningof typical stiffener-frame connections

— Assess shear flow distribution fromlongitudinal stiffener to web frame

Very fine meshFE model 3)

— Very fine mesh (t × t)— Sub-model— Size such that boundary effects are avoided— Include local pressure loads— Net scantlings (see Pt.3 Ch.3 Sec.2 or CSR Pt.1 Ch.3

Sec.2)

— Establish stress concentration factorsfor longitudinal stiffener-frameconnections

— Establish hot spot stress

1) Detailed modelling principles are further outlined in DNVGL-CG-0127, Finite element analysis, [3].2) Detailed modelling principles are further outlined in DNVGL-CG-0152, PLUS3) Detailed modelling principles are further outlined in DNVGL-CG-0129, Fatigue assessment of ship structure, [6.3].4) Application of each FE model type are further outlined in DNVGL-CG-0152, PLUS

3.3 Fatigue critical details3.3.1 Selection criteriaAn overview of typical fatigue critical details subject to fatigue strength assessment are given in [3.3.2] and[3.3.3]. Additional details may be required on a case-by-case basis.The results obtained for the critical details being assessed shall be extrapolated to other locations of similardetails.

3.3.2 High cycle fatigue critical detailsHigh cycle fatigue critical details that shall be assessed are given in Table 5.High cycle fatigue assessment around openings in way of other longitudinal strength members than the maindeck, e.g. tween decks and bottom, may be required on a case-by-case basis.

Table 5 Overview of high cycle fatigue critical details - Plus

Detail Location Selection criteria Stress concentration method

Longitudinal stiffener-frameconnections to:

— web stiffener— cut out— lug plate

— One frame amidships 1)

— One frame in foremost hold 1)

— One frame in aftmost hold 1)

All connection typesi.w.o.:

— bottom— inner bottom— side— inner side— hopper tank

Fine mesh FE model withtabulated stress concentrationfactors 2)

Stringer heels and toes— one location amidships— one location in foremost hold— one location in aftmost hold

Based on screeningof cargo hold model

Stress concentration model(very fine mesh)

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Bottom and side shell platingconnection to stiffener andframes

— One frame amidships— One frame in foremost hold— One frame in aftmost hold

All connections Cargo hold model with tabulatedstress concentration factors 2)

Main deck plating, includingstress concentrations from:

— openings— scallops— pipe penetrations— attachments

All deck openings and deckdetails within the cargo holdregion

All deck openingsand deck detailswithin the cargohold region 3)

Stress concentration model(very fine mesh), or cargo holdmodel with tabulated stressconcentration factor 2)

1) Except from frames adjacent to transverse bulkheads, all other frames within the cargo hold region shall bescreened in order to predict the fatigue life by using scaling factors multiplied with reference stress from the cargohold models. The scaling factors shall be established by use of the fine mesh FE models. Details are given in DNVGL-CG-0152, PLUS

2) Tabulated stress concentration factors of typical details are given in DNVGL-CG-0152, PLUS3) The fatigue life requirements for the deck plating will be satisfied provided that the target fatigue life is obtained

with a stress concentration factor kG = 3.0.

3.3.3 Low cycle fatigue critical detailsShips with internal structural members exposed to repeated high cyclic static loads alternating betweentension and compression due to cargo loading and unloading shall be assessed. Low cycle fatigue criticaldetails that shall be assessed are given in Table 6.

Table 6 General overview of low cycle fatigue critical details - Plus


Longitudinal stiffener-frameconnections to:

— web stiffener 1)

— cut out 2)

— lug plate 2)


Typical connectiontypes i.w.o.:

— inner bottom— hopper tank

Fine mesh FE model withtabulated stress concentrationfactors 3)

Stringer heels and toessubject to frequent alternateloading

Inner bottom connection totransverse bulkhead subjectto frequent alternate liquidloading

Lower stool connection toinner bottom subject tofrequent alternate liquidloading

— one location amidships— one location in foremost hold— one location in aftmost hold

Based on screeningof cargo hold model

Stress concentration model(very fine mesh)

1) In particular critical for large profiles with long span connected to a web stiffener on top of moderate size.2) In particular critical in way of areas with high girder shear stress, or when web stiffener is not fitted on top of

longitudinal flange.3) Stress concentration factors of typical details are given in DNVGL-CG-0152, PLUS

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3.4 Fatigue strength assessment3.4.1 High cycle fatigueThe fatigue strength assessment shall be carried out in accordance with Pt.3 Ch.9 Sec.4 or CSR Pt.1 Ch.9Sec.3 for the fatigue critical details specified in [3.3.2].The fraction of the total design life spent at sea should not be taken less than 0.85. The fraction of design lifein the fully loaded and ballast conditions should be taken according to Pt.3 Ch.9 Sec.4 Table 2 or CSR Pt.1Ch.9 Sec.1 [6]. Other fractions will be considered if request.

Guidance note:If the hole and cut-out plan is not available at an early design stage a preliminary document should be provided with allowable stressconcentration factors or FAT classes.


3.4.2 Low cycle fatigueTypical low cycle fatigue critical details that shall be assessed are specified in [3.3.3]. Low cycle fatiguestrength assessment shall be considered as significant yielding can cause cracks at hotspots even though thedynamic stress from wave loading is low.

Guidance note:A procedure for calculating the combined damage due to high cycle and low cycle fatigue acceptable to the Society is further outlinedin the Society's document DNVGL-CG-0129, Fatigue assessment of ship structure, App.H.


3.4.3 Standard details for longitudinal stiffener-frame connectionsFor standard details of longitudinal stiffener-frame connections with proven fatigue resistance fatiguestrength assessment will not be required.

Guidance note:Standard details of longitudinal stiffener-frame connections, where fatigue strength assessment is not required, are shown in theSociety's document DNVGL-CG-152, PLUS.


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SECTION 7 DIRECT ANALYSIS OF SHIP STRUCTURES - CSA

1 General

1.1 IntroductionThe additional class notation CSA(Computational Ship Analysis), specifies an extended scope of strengthverification focused on longitudinal structural members, global transverse members and primary supportingmembers, by use of wave load analysis and global structural model.

1.2 ScopeThe scope of additional class notationCSA (Computational Ship Analysis) is to add a supplementary levelof safety related to strength verification of longitudinal structural members, global transfer members andprimary supporting members. Such verification design requirements include: loading conditions for fatigueand ultimate strength, wave load and finite element analysis, fatigue and ultimate strength analysis relatedto yield and buckling capacity and hull girder strength, respectively. The rules in this section are consideredto satisfy the requirements for additional ultimate strength and fatigue assessment, in addition to thosespecified in main class requirements in combination with ship type requirements given in Pt.5, or CSR. Anoverall description is given in Table 1.The additional class notation CSA has four different alternatives represented by specific qualifiers. QualifierFLS1 represents the first level of the range of CSA notations, focusing on fatigue only. Qualifier FLS2addresses fatigue limit state evaluations, but with a more comprehensive analysis scope. The CSA(1) andCSA(2) notations cover ultimate limit state assessment in addition to the fatigue strength assessments.

Table 1 Calculation scope – CSA

Class notations Ultimate strength Fatigue strength locations Loads

CSA(FLS1) NA— Panel knuckles, stringer heels and toes,

discontinuous plating structure, see [3.5.2]— Ship type specific details, see [3.5.3]

Direct wave load

CSA(FLS2) NA

— Longitudinal stiffener-frame connections to webstiffener, cut out and lug plate, see [3.5.4]

— Bottom and side shell plating, see [3.5.4]— Strength deck plating i.w.o. openings and

attachments, see [3.5.4]— Details as defined for CSA(FLS1)

Direct wave load

CSA(1) — Yield and buckling— Hull girder capacity

— As for CSA(FLS1) Direct wave load

CSA(2) — Yield and buckling— Hull girder capacity

— As for CSA(FLS2) Direct wave load

1.3 Application1.3.1 Applicable ship typesThe CSA notation is primarily intended for:

— Tankers, gas carriers and ore carriers of conventional design.

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— Special design configurations related to main dimensions, hull form, structural arrangement and/or massdistribution (steel, equipment and cargo).

1.3.2 Qualifiers of the CSA notationThe class notations CSA(FLS1), CSA(FLS2), CSA(1) and CSA(2) can not be given independently of eachother as the higher level class notation also includes the scope of the lower level class notation as shown inTable 1.

1.4 Class notations1.4.1 CSAShips built in compliance with the requirements as specified in Table 2 may be assigned the additional classnotation related to structural strength and integrity as follows:

Table 2 Additional class notation - CSA


1 Fatigue strength control in accordance with CSA(FLS1) andultimate strength check based on direct load calculations

2 Fatigue strength control in accordance with CSA(FLS2) andultimate strength check based on direct load calculations

FLS1 Fatigue strength control based on direct load calculations

CSA

Mandatory:

No


[3]

FiS requirements:

NA

FLS2 Fatigue strength control based on direct load calculations withincreased scope compared to CSA(FLS1)


2 Documentation

2.1 Documentation requirements2.1.1 CSADocumentation shall be submitted as required by Table 3.

Table 3 Documentation requirements - CSA


Ship hull structure H084 – Wave load analysis See DNVGL-CG-0130, Wave load analysis, [12] formore details FI

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H081 – Global strength analysis

Global strength analysis, including:

— General information, see Pt.3 Ch.7 Sec.1 [4]— Detailed information, see DNVGL-CG-0127, Finite

element analysis, [1.2]

FI


Cargo hold FE model of hold amidships, including:


element analysis, [1.2]

FI


Very fine mesh FE models for details withouttabulated stress concentration factors, including:

— General information, see Pt.3 Ch.7 Sec.1 [4]— Detailed information, see DNVGL-CG-0129,

Fatigue assessment of ship structure, [6.3]

FI

H085 – Fatigue analysis See DNVGL-CG-0129, Fatigue assessment of shipstructure, For more details FI

H134 – Hole and penetrationplan

All holes and cut-outs in way of continuous memberswithin the cargo hold region FI




3.1 General3.1.1 Recognised computer programThe calculations as required in the following sub-sections shall be carried out by computer programs suppliedby or recognised by the Society. Recognised computer programs are programs applied by builders ordesigners where reliable results have been demonstrated to the satisfaction of the Society.Wave load analysis computer programs and their application will be especially considered.

3.1.2 Minimum net scantlingsThe net scantlings shall not be less than those determined by the main class requirements in combinationwith ship type requirements given in Pt.5, or CSR.

3.1.3 Fatigue assessment of critical details covered by both CSR and PlusCritical details being defined as scope for both CSA and Plus shall be checked in accordance with therequirements of CSA (direct loads and not rule loads).Critical details being defined as scope for Plus and not for CSA, e.g. longitudinal stiffener-frame connections,shall be checked in accordance with the requirements of Plus (rule loads).

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3.2 Loading conditions3.2.1 Loading conditions for fatigue strength assessmentThe loading conditions for fatigue strength assessment shall be based on the vessels loading manual andshall represent typical loading situations representative for most of the operational lifetime of the vesselwhile at sea. This includes one ballast condition and one full load condition.

3.2.2 Loading conditions for ultimate strengthThe loading conditions for ultimate strength shall be based on the vessels loading manual.The most demanding loading conditions, i.e. those giving the maximum stress in longitudinal material indifferent parts of the vessel shall be selected.For vessels where transverse capacity is of major interest, e.g. ro-ro vessels and catamarans, loadingconditions giving maximum stresses in transverse material will also relevant.The loading conditions are in addition to be defined to cover the full range of still water bending momentsand shear forces from maximum sagging to maximum hogging conditions.

3.3 Wave load analysis3.3.1 GeneralSea keeping and hydrodynamic load analysis shall be carried out using 3-D potential theory, with possibilityof forward speed, with a computer program recognized by the Society. Non-linear theory shall be used fordesign waves for ULS assessment, where non-linear effects are considered important. The program shallcalculate response amplitude operators (RAOs, transfer functions) and time histories for motions and loads.The inertia loads and external and internal pressures calculated in the hydrodynamic analysis shall be directlytransferred to the structural models.

Guidance note:Calculation methods acceptable to the Society are further outlined in the Society's document DNVGL-CG-0130, Wave loads.


3.3.2 Design basisThe wave load analysis shall be based on all wave headings (0° to 360°) with an equal probability ofoccurrence. The spacing between the headings shall not be greater than 30°.The range and density of wave periods shall ensure a proper representation of all relevant response transferfunctions (motions, sectional loads, pressures).

Guidance note:Typically wave periods in the range of 5-40 seconds, with 25-30 wave periods, can be used.


Speed, wave environment and probability level to be applied in the wave load analysis is given in Table 4.

Table 4 Speed, wave environment and probability level

Limit state Speed Scatter diagram Wave spectrum Wave spreading Load level

Fatigue strength 2/3 of servicespeed World wide 1), 2) 10-2 probability of

exceedance 3)

Ultimate strength 5 knots North Atlantic 2)Pierson-Moskowitz 2) COS2

Return period 25years 4)

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Limit state Speed Scatter diagram Wave spectrum Wave spreading Load level

1) For ships assigned CSR notation and for certain structural details, like cargo containment system of gas carriers, thefatigue assessment shall be based on North Atlantic wave environment. North Atlantic wave environment may beapplied for other ship types if request.

2) Details are given in DNVGL-CG-0130, Wave loads, [3].3) For splash zone and mean stress effect. See DNVGL-CG-0130, Wave loads, [10] for more details.4) Longer design life will be applied if requested.

3.3.3 Load transferA load transfer (snap-shot) from the hydrodynamic analysis to the structural analysis shall be performedwhen the total load/response from the hydrodynamic time-series is at its maximum/minimum. The loadtransfer shall include both gravitational and inertial loads, and the still water and wave pressures.Typical design waves to be applied to the structural analysis are given in [3.3.4].

3.3.4 Design waves for ultimate limit stateThe design waves used in the hydrodynamic analysis shall be transferred to the structural models and shallcover the entire ship length. Different design waves shall be used to check the capacity of different parts ofthe ship. Typical design waves are shown in Table 5. For certain ship types some of the design waves may bewaived, or additional design waves may be required on a case-by-case basis.Design waves which represents vertical bending moment and vertical shear force (1A to 3B) shall beperformed with non-linear hydrodynamic analysis. The remaining design waves may be performed with linearhydrodynamic analysis.

Table 5 Guidance on loading condition selection

Design Condition Loading condition & design loads

ID

Referenceload/response

(Dominant or maxload/response)

Design area Loading condition Typical loadingpattern

Design wave(maximised

response/load)

1A Hogging bendingmoment Entire ship length Max midship hogging

bending momentMax hogging wavemoment

1B Sagging bendingmoment Entire ship length Max midship sagging

bending momentMax sagging wavemoment

2A 3) Hogging + doublebottom bending

Midship doublebottom

Large hoggingcombined with deepdraft

Hold(s) emptyacross withadjacent hold(s)full

Max hogging wavemoment

2B 3) Sagging + doublebottom bending

Midship doublebottom

Large saggingcombined with lowdraft

Hold(s) fullacross withadjacent hold(s)empty

Max sagging wavemoment

3A 2) Shear force at aftquarter-length

Aftmost hold shearelements

Max shear force ataftquarter-length

Max wave shear forceat aft quarter-length

3B 2) Shear force at fwdquarter-length

Foremost hold shearelements

Max shear force at fwdquarter-length

Max wave shear forceat fwd quarter length

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Design Condition Loading condition & design loads

ID

Referenceload/response

(Dominant or maxload/response)

Design area Loading condition Typical loadingpattern

Design wave(maximised

response/load)

4A 3) Internal pressure/load in foremost hold

Foremost holddouble bottom

Loaded at low draftfwd

Foremost hold(s)full across withno.2 hold(s)empty

Max verticalaccelerations atforemost hold in headsea

4B 3) External pressure atforemost hold

Foremost holddouble bottom

Loaded at deep draftfwd

Foremost hold(s)empty acrosswith no.2 hold(s)full

Max bottom wavepressure at foremosthold in head sea

5Combined vertical,horizontal andtorsional bending

Entire ship length

Loaded condition withhigh GM combinedwith large hoggingfor hogging vesselsor large sagging forsagging vessels

Full stochastic or designwave(s) in quartering/beam sea condition 1):

— max torsion— max horizontal

bending— max stress at

hatch corners/largeopenings

6 Max transverseloading/accelerations Entire ship length Loaded with maximum

GM

Full stochastic ormaximum transverseacceleration

7 Max transversecompression

Transversebulkheads andstrength decksalong entire shiplength

Loaded with maximumGM

Full stochastic ormaximum sea pressure

1) Headings contributing to a linear long term response of vertical bending moment greater than the maximum non-linear snap-shot (typical head seas and following seas) shall be neglected. The long term response of the vertical

bending moment for the chosen headings shall not be less than the long term response with all headings on a 10-6.5

probability level (one year return period).2) Design waves for max shear force may in some cases be combined with design waves for max bending moment (1A

and 1B).3) Only applicable if such loading pattern are included in the loading manual.

3.4 Finite element analysis3.4.1 Required structural modelsCharacteristics and application of different structural model types are given in Table 6.A global FE model of the entire ship shall be used to represent the overall stiffness of the ship.A Cargo hold FE model shall be used to represent the overall stiffness of the primary supporting members.The hot spot stresses are obtained either by use of tabulated stress concentration factors or very fine meshFE models.Fatigue pressure loads shall be applied to the structural models in accordance Pt.3 Ch.4 or CSR Pt.1 Ch.4.

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Table 6 Required FE models - CSA

Model type Characteristics Application

Global FE model 1)

— The whole structure of the vessel— Girder spaced mesh (S x S)— May include cargo hold FE model with

stiffener spaced mesh (b × b)— May include very fine mesh (t × t)— Includes mass-model— Net scantlings (see Pt.3 Ch.3 Sec.2 or CSR

Pt.1 Ch.3 Sec.2)

— Boundary conditions for sub-models— Screening of fatigue critical details— Yield strength and buckling assessment of

global strength members— Nominal stress for fatigue strength assessment

in combination with tabulated stressconcentration factors

Cargo hold FEmodel 2)

— Part of vessel (typical cargo-hold model)— Stiffener spaced mesh (b × b)— May include very fine mesh (t × t)— Includes mass-model and local pressure

loads— Net scantlings (see Pt.3 Ch.3 Sec.2 or CSR

Pt.1 Ch.3 Sec.2)

— Screening of fatigue critical details— Yield strength and buckling assessment of

primary supporting members— Relative deflection analysis for fatigue

assessment of stiffener end connections in wayof transverse bulkheads.

— Nominal stress for fatigue assessmentin combination with tabulated stressconcentration factors

Very fine mesh FEmodel 3)

— Very fine mesh (t × t)— Sub-model— Size such that boundary effects are avoided— Include local pressure loads— Net scantlings (see Pt.3 Ch.3 Sec.2 or CSR

Pt.1 Ch.3 Sec.2)

— Fatigue strength assessment— Yield strength

1) Detailed modelling principles are further outlined in DNVGL-CG-0127, Finite element analysis, [2].2) Detailed modelling principles are further outlined in DNVGL-CG-0127, Finite element analysis, [3].3) Detailed modelling principles are further outlined in DNVGL-CG-0129, Fatigue assessment of ship structure, [6.3].

3.5 Fatigue critical details3.5.1 Selection criteriaOverview of typical fatigue critical details subject to fatigue strength assessment are given in [3.5.2] to[3.5.4]. Additional details may be required on a case-by-case basis.The results obtained for the critical details being assessed shall be extrapolated to other locations of similardetails.

3.5.2 General fatigue critical details CSA(FLS1)Fatigue critical details independent of ship type that shall be assessed as required by CSA(FLS1) are given inTable 7.

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Table 7 General overview of fatigue critical details - CSA(FLS1)

Detail Location Stress concentrationmethod

Fatigue calculationMethod 1)

Stringer heels and toes— One location amidships— One location in foremost hold— One location in aftmost hold

Panel knuckles — One lower hopper knuckle amidships

Stress concentrationmodel (very fine mesh) Full stochastic

1) Fatigue calculation methods are further outlined in DNVGL-CG-0129, Fatigue assessment of ship structure.

3.5.3 Ship type fatigue critical details CSA(FLS1)Fatigue critical details depending on ship type that shall be assessed as required by CSA(FLS1) are given inTable 8.

Table 8 Ship type specific overview of fatigue critical details - CSA(FLS1)

Ship type Location Stress concentrationmethod


Tankers

— Lower hopper knuckle amidships, foremost hold andaftmost hold

— Upper hopper knuckle amidships, foremost hold andaftmost hold

— Stringer heels and toes amidships, foremost holdand aftmost hold

Membrane typeLNG carriers


— Upper hopper knuckle amidships, foremost hold andaftmost hold


— Dome opening and coaming amidships— Lower and upper chamfer knuckles amidships— All longitudinal double bottom girders in way of

transverse bulkhead amidships— Trunk deck at transverse bulkhead amidships— Transition of hold nos. 1 and 2 for non-continuous

longitudinal bulkhead— Aft trunk deck scarfing

Stress concentrationmodel (very fine mesh) Full stochastic

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Ship type Location Stress concentrationmethod


LNG carrierswith sphericaltanks of type B



— Tank cover to deck connection amidships in way ofCL, 45º off CL and 90º off CL.

— Tank skirt connection to foundation deck amidships,foremost hold and aftmost hold

— Inner side connection to foundation deck in themiddle of the tank web frame amidships, foremosthold and aftmost hold

— All longitudinal double bottom girders in way oftransverse bulkhead amidships

LPG carrierswith prismatictanks of type A

— Dome opening and coaming amidships— Lower and upper side bracket amidships— All longitudinal double bottom girders in way of

transverse bulkhead amidships

Ore carriers

— Inner bottom and longitudinal bulkhead connectionamidships, foremost hold and aftmost hold

— Stringer heels and toes in ballast tank amidships,foremost hold and aftmost hold

— Cross-tie connection in ballast tank amidships,foremost hold and aftmost hold

— Hatchway corner amidships— Longitudinal hatch coaming brackets amidships


3.5.4 General details CSA(FLS2)Fatigue critical details independent of ship type that shall be assessed as required by CSA(FLS2), in additionto those required in Table 8 for CSA(FLS1), are given in Table 9.Fatigue assessment around openings in way of other longitudinal strength members than the main deck, e.g.tween decks and bottom, may be required on a case-by-case basis.

Table 9 General overview of fatigue critical details - CSA(FLS2)

Detail Location Selection criteria Stress concentrationmethod

FatiguecalculationMethod 2)

End connections oflongitudinals

— One frame amidships— One bulkhead amidships— One frame in foremost hold— One frame in aftmost hold

All stiffeners included

Bottom and side shellplating connection tostiffener and frames


All connections

Cargo hold modelwith tabulated stressconcentration factors 1)

Componentstochastic

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Detail Location Selection criteria Stress concentrationmethod

FatiguecalculationMethod 2)

Main deck plating,including stressconcentrations from:

— openings— scallops— pipe penetrations— attachments

All deck openings and deckdetails within the cargo holdregion

Based on globalscreening analysisand evaluation ofdetails

Stress concentrationmodel (very fine mesh),or cargo hold modelwith tabulated stressconcentration factors 1)

Fullstochastic

1) Tabulated stress concentration factors of typical details are given in DNVGL-CG-0129, Fatigue assessment of shipstructure, App.A.


3.6 Fatigue strength assessment3.6.1 GeneralThe fatigue strength assessment shall be carried out in accordance with Pt.3 Ch.9 Sec.4 or CSR Pt.1 Ch.9Sec.3 for the fatigue critical details specified in [3.5].The fraction of the total design life spent at sea should not be taken less than 0.85. The fraction of design lifein the fully loaded and ballast conditions should be taken according to Pt.3 Ch.9 Sec.4 Table 2 or CSR Pt.1Ch.9 Sec.1 [6]. Other fractions will be considered if request.

Guidance note:If the hole and cut-out plan is not available at an early design stage a preliminary document should be provided with allowable stressconcentration factors or FAT classes.


3.7 Yield and buckling capacity3.7.1 Ultimate strength analysisFor CSA(1) and CSA(2) ultimate strength analysis shall be carried out for all global strength members,primary supporting members covered by the cargo hold FE model, and critical details that may need specialconsideration by use of very fine mesh. Required scope with acceptance criteria is further shown in Table 10.

Table 10 Ultimate limit state - structural members to be checked and acceptance criteria

Model type Members Acceptance criteria

Global FE model

— Longitudinal hull girder strength members; and— Global transverse strength members (transverse bulkheads

and strength decks)

throughout the whole ship’s length

Cargo hold model FEmodel All primary supporting members within the cargo hold model 1)

— Yielding, see [3.7.2]— Buckling, see [3.7.4]

Very fine mesh FEmodel Hatchway corners and critical frame corners 1) Peak stress, see [3.7.3]

1) The results obtained shall be extrapolated to similar members outside of the model boundaries.

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3.7.2 Yield strength criterionAllowable von Mieses stress, in N/mm2:

σvm = 0.95 ReH

3.7.3 Linear peak stress criterionLocal linear peak stresses in areas with pronounced geometrical changes, such as in hatch corners, framecorners etc., may need special consideration. Local peak stresses in this context are stresses calculated withvery fine mesh FE models that have a finer finite element mesh representation than used for nominal stressdetermination.For extreme 25 year North Atlantic loads, linear von Mieses peak stress, in N/mm2, for an area of 50 mm x50 mm corresponding to an acceptable equivalent plastic strain is:

σvm = 400/kLocal peak stress as given above may be accepted provided plastic mechanisms are not approached(developed) in the associated structural parts. Low cycle fatigue strength assessment may also be requiredon a case-by-case basis for areas with high static peak stresses due to cargo loading and unloading.

Guidance note:Areas above yield determined by a linear finite element method analysis may give an indication of the actual area of plastification.Otherwise, a non-linear finite element method analysis may need to be carried out in order to trace the full extent of the plastic zone.


3.7.4 Buckling strengthThe buckling strength assessment shall comply with the requirements given in Pt.3 Ch.8 Sec.4.For buckling strength assessment of global strength members with girder spaced mesh (S x S), themaximum allowable buckling utilization factor shall be taken as:

— 1.0 in general— 0.95 for members of double bottom and double side skin construction.

For buckling strength assessment of cargo hold model with stiffener spaced mesh (b x b), the maximumbuckling utilization factor shall be taken as 1.0.

3.8 Hull girder ultimate strength3.8.1 GeneralFor CSA(1) and CSA(2) the ultimate sagging and hogging bending capacity of the hull girder shall bedetermined, for both intact and damaged conditions.

3.8.2 Damage conditionsThe following damage conditions shall be considered independently, using the worst possible position in eachcase:1. Collisionwith penetration of one ship side, single or double side, within a breadth of B/16.The damage extents are shown in Figure 1 and given by Table 11:

Table 11 Damage conditions - Collision

Damage extentModel type

Single side Double side

Height: h/D 0.75 0.60

Length: l/L 0.10 0.10

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Single side Double side

1) h = penetration height2) l = penetration length

Guidance note:Calculations utilising symmetrical characteristics, i.e. the capacities of the damaged parts of the cross section are reduced with 50%on both sides of the ship, will be accepted.


2. Groundingwith penetration of bottom, single or double bottom, within a height hd, to be taken as the smaller of B/20and 2.0 m.The damage extents are shown in Figure 1 and given by Table 12:

Table 12 Damage conditions - Grounding


Single bottom Double bottom

Height: b/B 0.75 0.55

Length: l/L 0.50 0.30

1) b= penetration breadth

Figure 1 Damage extent collision (left) and grounding (right)

3.8.3 Required ultimate capacityThe Ultimate Strength MU shall be checked for the weakest interframe cross-section including all relevantlocal load and double bottom bending effects.The ultimate hull girder capacities in intact and damaged conditions shall comply with the criteria given inTable 13.

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Table 13 Hull girder strength check: accept criteria – required safety factors

Intact strength Damage strength

MS + γW1 MW ≤ MU1 / γM γS MS + γW2 MW ≤ MUD / γM

where:MS = maximum design sagging or hogging still

water moment according to the loadingconditions from the loading manual usedin the wave load analysis, in kNm

MW = design wave bending moment accordingto the wave load analysis in [3.3], in kNm

MU1 = hull girder bending moment capacity inintact condition, in kNm, according to Pt.3Ch.5 Sec.5

γW1 = 1.1 (partial safety factor on MW forenvironmental loads)

γM = 1.15 (material factor) in generalγM = 1.25 (material factor) to be considered

for hogging checks of designs with bi-axial/shear stresses conditions in bottomarea of such a magnitude that theywill significantly reduce the hull girdercapacity

where:MS = maximum design sagging or hogging still water

moment according to the loading conditions from theloading manual used in the wave load analysis, in kNm

MW = design wave bending moment according to the waveload analysis in [3.3], in kNm

MUD = hull girder bending moment capacity in damagedcondition, in kNm, according to Pt.3 Ch.5 Sec.5

γS = 1.1 (factor on MS allowing for moment increase withaccidental flooding of holds)

γW2 = 0.67 (wave load reduction factor corresponding to 3month exposure in world-wide climate)

γM = 1.0 (material factor) in generalγM = 1.10 (material factor) to be considered for hogging

checks of designs with bi-axial/shear stressesconditions in bottom area of such a magnitude thatthey will significantly reduce the hull girder capacity

Guidance note:The ultimate sagging and hogging bending capacity of the hull girder may be assessed using recognised non-linear FE programs inaccordance with procedures outlined in the Society's document DNVGL-CG-0128, Buckling analysis, [6].


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SECTION 8 GLOBAL STRENGTH ANALYSIS OF CONTAINER SHIPS -RSD

1 General

1.1 IntroductionThe additional class notationRSD (Rational Ship Design) is only applicable to container ships and includesan extended scope of strength verification of longitudinal members, global transverse members and primarysupporting members, by use of equivalent design waves obtained from wave load analysis, and globalstructural model.

1.2 ScopeThe scope of additional class notation RSD(Rational Ship Design) is to add a supplementary level of safetyrelated to strength verification of longitudinal members, global transverse members and primary supportingmembers. Such verification design requirements include: loading conditions for fatigue and ultimate strength,wave load and finite element analysis, fatigue and ultimate strength analysis related to yield and bucklingcapacity and hatch cover movement, respectively. The rules in this section are considered to satisfy therequirements for global finite element analysis of the entire ship in verifying the structural adequacy of thelongitudinal and transverse primary structure. In particular, the scantlings of members that are influencedmainly by the torsional moment e.g. radii of the hatch corners, face plates and horizontal girders of thetransverse bulkheads, shall be checked based on the global finite element analysis.

1.3 ApplicationShips with ship type class notation Container ship having one or more of the characteristics listed in Table 1will be assigned the additional notation RSD, related to structural strength and integrity.Ships with ship type class notation Container ship not having any of the characteristics listed in Table 1may, upon request, be assigned the RSD notation.

1.4 Class notations1.4.1 RSDShips built in compliance with the requirements as specified in Table 1 will be assigned the additional notationrelated to structural strength and integrity as follows:

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Table 1 Additional class notation - RSD


RSD

Mandatory:

Yes


[3]

FiS requirements:

NA

<None>Structural strength is verified bymeans of global finite elementassessments

Mandatory for ships with class notationContainer ship having minimum one of thefollowing characteristics:

— Novel design— Complex structural arrangement— L ≥ 330 m— B ≥ 47 m— V ≥ 25 kn— Hatch coaming build of VL-47 steel


2 Documentation

2.1 Documentation requirements2.1.1 RSDDocumentation shall be submitted as required by Table 2.

Table 2 Documentation requirements - RSD


H084 – Wave load analysis See DNVGL-CG-0131, Container ships, [2.1.4] formore details FI

H081 – Global strength analysis

Global strength analysis, including:


element analysis, [1.2] and DNVGL-CG-0131,Container ships, [2]

FI


Local models for details without FAT classes,including:

— General information, see Pt.3 Ch.7 Sec.1 [4]— Detailed information, see DNVGL-CG-0131,

Container ships, [2.2]

FI

Ship hullstructure

H085 – Fatigue analysis See DNVGL-CG-0129, Fatigue assessment of shipstructure, For more details FI


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3.1 General3.1.1 Recognised computer programThe calculations as required in the following sub-sections shall be carried out by computer programs suppliedby or recognised by the Society. Recognised computer programs are programs applied by builders ordesigners where reliable results have been demonstrated to the satisfaction of the Society.Wave load analysis computer programs and their application will be specially considered.

3.2 Loading conditions3.2.1 Ultimate Limit State (ULS) loading condition with maximum still water bending momentMaximum displacement at scantling draught with maximum permissible vertical hogging still water bendingmoment shall be considered. A homogenous weight distribution in all bays with a high stack load for thecontainers on the deck shall be used for this loading condition, limited by sufficient stability. The maximumused charge for water ballast, fuel etc. is limited to around 30 % of the total cargo weight. The hold of themidship area shall be loaded with 40’ containers while all other holds may be loaded by either 20’ or 40’containers. A relatively low GM (metacentric height) for the vessel’s size will be achieved with this loadingcondition.

3.2.2 Ultimate Limit State (ULS) loading condition with minimum still water bending momentMaximum displacement at scantling draught with minimum possible vertical hogging or maximum saggingstill water bending moment shall be considered. For the hold containers all bays shall be used. The deckcontainers shall be arranged in the midship area as it is necessary to achieve the target MS. For hold anddeck containers a relatively high uniform weight shall be used. The maximum used charge for water ballast,fuel etc. is limited to 20% of the total cargo weight. The use of 20’ or 40’ containers in the hold and on thedeck is optional. A relatively high GM (metacentric height) for the vessel’s size will be achieved with thisloading condition.

3.2.3 Fatigue Limit State (FLS) loading conditionsFor fatigue limit state, same loading conditions as given [3.2.1] and [3.2.2] shall be investigated, with stillwater bending moments and draughts in accordance with Pt.3 Ch.9 Sec.4 Table 2.

3.3 Wave load analysis3.3.1 GeneralHydrodynamic load analysis shall be carried out with possibility of forward speed.

Guidance note:Calculation methods acceptable to the Society are further outlined in the Society's document DNVGL-CG-0131, Container ships,[2.1.4] and [2.1.5].


3.3.2 Design basisThe wave load analysis shall be based on all wave headings (0° to 360°). Due to symmetry of the shipsgeometry, it is sufficient to consider wave directions from one side only. The spacing between the headingsshall not be greater than 30°.

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Speed, design wave amplitude and probability level to be applied in the wave load analysis are given in Table3.

Table 3 Speed, design wave amplitude and probability level

Limit state Speed Basis for design wave amplitude 1) Load level

Fatigue strength (FLS) Mwv2) 10-2 probability of exceedance

Ultimate strength (ULS)2/3 of service speed

Mwv with fp = 0.75 10-6 probability of exceedance

1) Methods how to establish design wave amplitude are further outlined in DNVGL-CG-0131, Container ships, [2.1.4].2) Mwv as defined in Pt.3 Ch.4 Sec.4.

3.3.3 Equivalent design wave conceptFor each loading condition as given in [3.2] dynamic load cases based on the equivalent design wave conceptshall be established, applying the design basis given in [3.3.2].

3.3.4 Loads on bow and stern structureBow impact and stern slamming loads shall be established applying mean pressures according to Pt.3 Ch.10Sec.1 and Pt.3 Ch.10 Sec.3

3.4 Finite element analysis3.4.1 Required structural modelsGlobal finite element models shall be based on the gross scantling approach, i.e. all structures shall bemodelled with gross offered scantling, excluding any owner’s voluntary addition.The focus of the global strength analysis for a container ship is on the evaluation of global stresses anddeformations under particular consideration of torsional response, which is significant due to large hatchopenings.Characteristics and application of different structural model types are given in Table 4.

Table 4 Required FE models - RSD


Global FE model 1)

— The whole structure of the vessel— Girder spaced mesh— Includes mass-model

— Boundary conditions for sub-models— Yield strength and buckling assessment of

strength members— Nominal stress for fatigue strength

assessment in combination with FAT classes

Local model 2)

— Fine mesh— Sub-model or local fine mesh area in

global FE model

Fatigue assessment of:

— Hatch corners— Knuckles and discontinuities of longitudinal

members in upper part of hull girder

1) Detailed modelling principles are further outlined in DNVGL-CG-0127, Finite element analysis, [1.2] and DNVGL-CG-0131, Container ships, [2.1.3].

2) Detailed modelling principles are further outlined in DNVGL-CG-0131, Container ships, [2.2].3) Fatigue application are further outlined in DNVGL-CG-0131, Container ships, [2.2].

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3.5 Fatigue critical detailsContainer ship fatigue critical details that shall be assessed as required by the RSD notation are given inTable 5

Table 5 Overview of fatigue critical details - RSD

Detail Location Stress type used forfatigue assessment 1)

End connections of longitudinalsin side shell and bilge

— Ordinary web frames and at support bulkhead of onecargo hold in the midship area

— Ordinary web frames and at support bulkhead atlocations where the structural arrangement changessignificantly within 0.2L an 0.8L

— Watertight bulkheads and at adjacent ordinary webframes in cargo hold area within 0.2L and 0.8L

Nominal stress fromglobal FE model incombination with hotspot stress concentrationfactors

Welded details in the upper partof hull girder, such as:

— transverse butt welds— hatch cover resting pads— equipment holders

Nominal stress fromglobal FE model incombination with FATclasses2) or hot spotstress concentrationfactors

Knuckles and discontinuities oflongitudinal members in upperpart of hull girder, such as:

— hatch coamings

All locations within the cargo hold region(s)

Hatch corners All hatch corners within the cargo hold region(s)

Hot spot or local stressfrom local model

Flange intersections of stringersand vertical girders of transversebulkhead

All locations within the cargo hold region(s)

Nominal stress fromglobal FE model incombination with FATclasses2) or hot spotstress concentrationfactors

1) Fatigue assessments are further outlined in DNVGL-CG-0131, Container ships, [2.2].2) FAT classes of typical details are given in DNVGL-CG-0129, Fatigue assessment of ship structure, App.A.

3.6 Fatigue strength assessment3.6.1 GeneralThe fatigue strength assessment shall be carried out in accordance with Pt.3 Ch.9 Sec.4 for the fatiguecritical details specified in [3.5].The fraction f0 of the total design life spent at sea should be taken according to Pt.3 Ch.9 Sec.4 Table 2. Thetwo loading conditions, minimum and maximum hogging condition, shall be checked separately. The lowestfatigue life from the two loading conditions is representative of the calculated fatigue life. For each loadingcondition, the ballast tank shall be considered as full (to the tank top) for the whole fatigue design life.

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3.7 Yield and buckling capacity3.7.1 YieldStresses in plating of all hull girder structural members, primary supporting structural members andbulkheads shall not exceed the permissible values as given in Table 6:

Table 6 Permissible stresses for global finite element analysis

Permissible axial& principal stress

Permissibleshear stress

Permissible vonMises stress

Girder spaced mesh 175/k 110/k 190/k

Stiffener spaced mesh, when provided 195/k1) 120/k1) 210/k1)

1) In way of structural discontinuities, like brackets or modeled openings, a 6% higher stress level is acceptable.

3.7.2 BucklingFor plating of all hull girder structural members, primary supporting structural members and bulkheads averification against the buckling criteria shall be carried out in accordance with Pt.3 Ch.8 Sec.4. For girderspaced mesh with a partial safety factor of S = 1.10, and for stiffener spaced mesh with a partial safetyfactor of S = 1.05.

3.8 Hatch cover movementsSpecial consideration shall be given to movements between hatch cover and ship structure or between hatchcover panels. Relative horizontal plane deflections as described in the Society's document DNVGL-CG-0131,Container ships, [2.3] shall be calculated and submitted for information with the hatch cover drawings.

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SECTION 9 PERFORMANCE STANDARD FOR PROTECTIVE COATINGS- COAT-PSPC

1 General

1.1 IntroductionAdditional class notation COAT-PSPC gives requirements for corrosion prevention (coating) of tanks, spacesand areas, in accordance with the IMO performance standard for protective coating. These requirements willalready be covered by main class rules for SOLAS compliant vessels. The IMO-PSPC standard shall also applyto MODU Code compliant vessels, where the owner has voluntarily requested compliance with IMO-PSPC.

1.2 ScopeThe scope of additional class notation COAT-PSPC is to add an increased level of safety related to corrosionprevention in tanks, areas and spaces, in accordance with specified coating system standards, aligned tostatutory [SOLAS and MODU Code] requirements, and IMO/IACS interpretations. The rules in this sectionare considered to satisfy the requirements for corrosion prevention (coating) of tanks, spaces and areas,applicable for SOLAS and MODU Code compliant vessels, and when compliance with the IMO-PSPC standardhas been requested by the owner. The design criteria includes a qualifier X, where X denotes additionalrequirements for; seawater ballast tanks, cargo oil tanks, double skin spaces and void spaces; for all typesof vessel. A coating technical file [CTF] is required to be compiled by the shipyard and shall be reviewed byDNV GL, as shall the inspection agreement. Qualifications for coating inspectors, type approval and inspectionrequirements have also been included.

1.3 Application

1.3.1 The additional class notation Coat-PSPC(X) is intended for all SOLAS and MODU Code vessels, butmay be assigned to all types of vessel. In cases where the difference between the requirements given in thissection and the latest edition of the IMO/IACS documents given as reference documents in [1.5], the contentof IMO/IACS documents and interpretations shall be applied.

1.3.2 The class notation Coat-PSPC(X) is an optional class notation intended for:

— use prior to the SOLAS requirements enter into force, or— vessels that are not required to comply with SOLAS (non-SOLAS vessels; e.g. vessels with Gross Tonnage

(GT) below the limits set in the different SOLAS regulations, Fishing Vessels, etc.), or— vessels that shall comply with MODU Code (Code for the Construction and Equipment of Mobile Offshore

Drilling Units).

1.3.3 The application of the class notation Coat-PSPC(X) is voluntary as compliance is already documentedby issuance of Safety Construction Certificate, although it may be used to document or visualize compliancewith both mandatory and non-mandatory SOLAS regulations:

— the class notation Coat-PSPC(X) is mainly intended for vessels where the IMO PSPC’s are not SOLASrequirements

— the class notation Coat-PSPC(X) may also be requested for vessels following the SOLAS requirements,however, this will then be more for visualisation purpose as compliance is already documented by issuanceof the vessels’ safety certificate.

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1.4 Class notations1.4.1 Coat-PSPCShips built in compliance with the requirements as specified in Table 1 may be assigned the additionalnotation related to structural strength and integrity as follows:

Table 1 Additional class notation - Coat-PSPC


Coat-PSPC

Mandatory:

No


[3]

FiS requirements:

Pt.7

X

Additional requirements for corrosionprevention of tanks and spaces/areasfor newbuildings. The notation providescompliance with: SOLAS Ch.II-1 Pt.A-1,Reg.3-2 and IMO Res. MSC.215(82);and SOLAS Ch.II-1, Reg.3-11 and IMORes. MSC.288(87)

The X denotes:B requirements for dedicated seawaterballast tanks of all types of vessel;

C requirements for cargo oil tanks ofcrude oil tankers;

D requirements for double-skin spacesof bulk carriers;

V requirements for void spaces of bulkcarriers and oil tankers

Guidance note:The qualifiers may be combined, e.g. a bulk carrier may have a class notation Coat-PSPC(B, D, V).


1.5 References1.5.1 Statutory requirementsThe Coat-PSPC(X) notation may be given to newbuildings built in compliance with:

— SOLAS Chapter II-1, Part A-1, Regulation 3-2 and the IMO Resolution MSC.215(82): PerformanceStandard for Protective Coatings (PSPC) for Dedicated Seawater Ballast Tanks in All Types of Ships andDouble-Side Skin Spaces of Bulk Carriers

— SOLAS Chapter II-1, Part A-1, Regulation 3-11 and the IMO Resolution MSC.288(87): PerformanceStandard for Protective Coatings (PSPC) for Cargo Oil Tanks of Crude Oil Tankers

— IMO Resolution MSC.244(83): Performance Standard for Protective Coatings for Void Spaces on BulkCarriers and Oil Tankers

— MSC.1/Circ.1279: Guidelines for Corrosion Protection of Permanent Means of Access Arrangements, asrelevant.Guidance note:The requirements of IMO Resolution MSC.244(83) are made voluntary by IMO.


1.5.2 Supporting documents with interpretation to statutory requirementsThe following reference documents are giving interpretations to the statutory requirements listed in [1.5.1]:

— IMO MSC.1/Circ.1421 Guidelines on Exemptions for Crude Oil Tankers solely engaged in the Carriage ofCargoes and Cargo Handling Operations not causing corrosion

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— IMO MSC.1/Circ.1465 Unified Interpretations of the Performance Standard for Protective Coatings forDedicated Seawater Ballast Tanks in all Types of Ships and Double-side Skin Spaces of Bulk Carriers(Resolution MSC.215(82))

— IMO MSC.1/1479, Unified Interpretation on the application of the Performance Standard for ProtectiveCoatings for Cargo Oil Tanks of Crude Oil Tankers (Resolution MSC.288(87))

— IMO Resolution MSC.291(87) Exemption of combination carriers or chemical tankers from PSPC-COT— IMO Resolution A.1076(28) Amendments to the survey guidelines under the harmonized system of survey

and certification (HSSC), 2011— IMO Resolution MSC.1/Circ.1381 Modifications to footnotes in the coating performance standards adopted

by resolutions MSC.215(82) and MSC.288(87)— IMO Resolution MSC.341(91) adoption of amendments to the performance standard for protective

coatings for dedicated seawater ballast tanks in all types of ships and double side skin spaces of bulkcarriers (resolution MSC.215(82))

— IMO Resolution MSC.342(91) adoption of amendments to the performance standard for protectivecoatings for cargo oil tanks of crude oil tankers (resolution MSC.288(87))

— IACS Unified Interpretations SC223 (IACS UI SC223) “For Application of SOLAS RegulationII-1/3-2 Performance Standard for Protective Coatings (PSPC-WBT) for Dedicated Seawater BallastTanks in All Types of Ships and Double-side Skin Spaces of Bulk Carriers, adopted by ResolutionMSC.215(82)” (regularly updated)

— IACS Unified Interpretations SC226.2 (IACS UI SC226.2) regarding ballast tanks in conversion projects— IACS Unified Interpretations SC227 (IACS UI SC227) The dedicated seawater ballast tanks in SOLAS

Chapter II-1 (Regulation 3-2) (regularly updated)— IACS Unified Interpretations SC258 (IACS UI SC258) For Application of SOLAS Regulation II-1/3-11

Performance Standard for Protective Coatings for Cargo Oil Tanks of Crude Oil Tankers (PSPC-COT),adopted by Resolution MSC.289 (87) The Performance Standard for Alternative Means of CorrosionProtection for Cargo Oil Tanks of Crude Oil Tankers

— IACS Unified Interpretations SC259 (IACS UI SC259) “For Application of SOLAS Regulation II-1/3-11Performance Standard for Protective Coatings for Cargo Oil Tanks of Crude Oil Tankers (PSPC-COT),adopted by Resolution MSC.288(87)” (regularly updated)

— IACS Recommendation No 116 “Performance Standard for Protective Coatings For Cargo Oil Tanks ofCrude Oil Tankers: 5 years field exposure test in accordance with MSC.288 (87).

— IACS Unified Requirements Z23 “Hull Survey for New Construction”.

2 Documentation

2.1 Documentation requirements2.1.1 CoatDocumentation shall be submitted as required by Table 2.

Table 2 Documentation requirements - Coat


M042 – Coating technical file (CTF), initial1) AP

M043 – Coating technical file (CTF), finalDedicated seawater ballast tanks for all vessels

FI, L, VS


M043 – Coating technical file (CTF), finalDouble-side skin spaces for bulk carriers

FI, L, VS

Coating

M042 – Coating technical file (CTF), initial1) Void spaces for bulk carriers and oil tankers AP

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M043 – Coating technical file (CTF), final FI, L, VS


M043 – Coating technical file (CTF), finalFor cargo oil tanks in crude oil tankers

FI, L, VS

1) The initial documentation (specifications and procedures) shall be submitted for approval prior to start of anycoating work (shop priming).




3.1 Corrosion prevention systems3.1.1 Requirements for corrosion prevention systemsA coating system shall be specified and applied to the tanks and spaces/areas, as described in the IMO PSPCsand IMO/IACS interpretation, for different types of ships.

Guidance note:Further details on the specifications can be found in the latest versions of the reference documents in [1.5]. PSPC requirements areminimum requirements, better standards can be used.


3.2 Coating Technical File (CTF)3.2.1 GeneralAll the IMO PSPC’s require the shipyard to compile a Coating Technical File (CTF) either in paper or electronicformat, or a combination of the two. If more than one of the three IMO PSPC’s shall be complied with, therequired documentation shall be gathered in one CTF, with separate sections describing each of the IMOPSPC’s.The Initial CTF shall contain all the information required by the IMO PSPC’s.

3.2.2 Inspection agreementInspection of surface preparation and coating processes shall be agreed between the ship owner, theshipyard/builder and the coating manufacturer. The inspection agreement shall be signed by the three partiesand presented to the Society by the shipyard for review prior to start of any coating work (shop primer).The Inspection Agreement shall, when a ship owner is known and a building contract exists, include thesignature of the ship owner.In cases where there is no building contract, and thereby no ship owner the shipyard will also take the roleas the “ship owner” until a real ship owner takes over the vessel constructed. The shipyard will then have tosign the Inspection Agreement also as the ship owner.In cases where a ship owner, originally having signed the Inspection Agreement, cancels the contract withthe shipyard and there is no longer a ship owner, the shipyard may either provide a new ship owner that cantake over the obligations from the previous ship owner, or the shipyard may decide to stay as the ship owneruntil the vessel is eventually sold. In such case the shipyard may either issue a letter confirming their new

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obligations (added as an attachment to the Inspection Agreement and the CTF) or the Inspection Agreementmay be revised to have the shipyard as the ship owner as well.

3.2.3 Type approvalsThe Society's type approval certificates for the main coating system, listing the relevant shop primers to beused (if any).

3.3 Yard coating inspectors3.3.1 Required qualifications for yard coating inspectorsTo ensure compliance with PSPC, Coating Inspectors shall inspect surface preparation and coating applicationduring the coating process by carrying out, as a minimum, those inspection items identified in IMO PSPC.Coating Inspectors shall be qualified to NACE Coating Inspector Level 2, FROSIO Inspector Level III, or anequivalent qualification. In addition to the NACE Level 2, Coating Inspectors shall also have at least 2 yearsrelevant experience.

Guidance note:Equivalent qualification: The Society offers review of such equivalent qualifications with basis in IACS UI SC223, PSPC 6, Section 3and IACS UI SC259, PSPC-COT, Section 3 to confirm that the training programme, including exams etc., is considered equivalent to:

— NACE CIP Level 2/CIP Level 2, maritime emphasis and

— FROSIO Inspector Course,

when applied to IMO PSPC / Resolution MSC.215(82) / Resolution MSC.288(87). A Certificate of Compliance is issued, normallyhaving 4 years validity.


3.3.2 Assistant coating inspectorsIf the Coating Inspector requires assistance from other persons to do the part of the inspections under theCoating Inspector’s supervision, those persons shall be trained to the Coating Inspector’s satisfaction. Suchtraining shall be recorded and endorsed either by the Coating Inspector, the shipyard's training organisationor inspection equipment manufacturer to confirm competence in using the measuring equipment andconfirm knowledge of the measurements required by the IMO PSPC. Training records shall be available forverification.

3.4 Review of coating technical file3.4.1 Initial review of CTFThe initial CTF including all the necessary information as defined in [3.2] shall be submitted for approval. Thedocument will be reviewed and stamped approved with the respective notation if found to satisfy the PSPCrequirements. Coating work (shop priming) shall not start before approval is given.

3.4.2 Inspection requirementsDuring the project, the implementation of IMO PSPC shall be monitored by the Society’s Surveyor. Thisimplies checking on a sampling basis that the Coating Inspector uses correct equipment, techniques andreporting methods. Similarly, the results from the surface preparation, coating logs and other inspectionreports are checked on a sampling basis. Appropriate information (e.g. Inspector’s working schedule orinspection planning) should be provided to the Society.

Guidance note:The attending Society’s Surveyor is not required by IMO/IACS regulation to attend any physical part of the coating process, but theSociety shall have the right to verify the resulting standards achieved in all relevant tanks.


3.4.3 Final review of CTF

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The final CTF, issued as a new revision to the initial CTF, shall be stamped with “Reviewed” and “And found tocomply with relevant Resolutions such as:

— IMO Resolution MSC.215(82) and/or— IMO Resolution MSC.288(87) and/or— IMO Resolution MSC.244(83) and/or— IMO MSC.1/Circ.1279”.

A Passenger Ship Safety Certificate or Cargo Ship Safety Certificate or Cargo Ship Safety ConstructionCertificate, or MODU Code Certificate, as appropriate, shall not be issued until the final CTF has been foundto be in compliance with the relevant IMO resolutions.The final CTF shall be kept on board the vessel as either electronic copy, paper copy or combination of bothand be updated, when relevant.

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SECTION 10 STRENGTHENING AGAINST COLLISIONS - COLL

1 General

1.1 IntroductionThe additional class notation COLL with qualifiers 1 to 6 gives an indication of the additional strengtheningof the hull side structure against a collision with another vessel, when compared to main class requirement incombination with ship type requirements and additional mandatory notations.

1.2 ScopeAdditional class notation COLL, with relevant qualifier, will be assigned under the provision that the ship hassufficient residual longitudinal strength in the damaged condition. Qualifiers 1 to 6 will be assigned based onthe defined characteristic ratio of the critical deformation energies, see Table 3.For general cargo ships and tankers, the notation COLL with a corresponding restrictive note in the appendixto the classification certificate may also be granted for individual compartments only.

1.3 ApplicationShips, whose side structures have been especially strengthened in order to resist collision impacts, may beassigned the additional class notation COLL with qualifiers 1 to 6.Qualifiers 1 to 6 result from the ratio of the critical deformation energies calculated for both the strengthenedside structure and the single hulled ship without ice or any other strengthening. The critical deformationenergy is defined as that amount of energy, when exceeded in the case of a collision, is expected to result ina critical situation.

1.4 Class notations1.4.1 COLLShips built in compliance with the requirements as specified in Table 1 may be assigned the additionalnotation related to structural strength and integrity as follows:

Table 1 Additional class notation - COLL


COLL

Mandatory:

No


[3]

FiS requirements:

NA

X Hull side structures especiallyevaluated for collision impacts

The qualifier X shall be an integral numberbetween 1 and 6, which denotes the amountof strengthening of the side structures againstcollisions

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T1,max = design draught, in m, of the striking shipT1,min = ballast draught, in m, of the striking shipT2,max = design draught, in m, of the struck shipT2,min = ballast draught, in m, of the struck shipVcr = critical speed, in knots, is the speed of the striking ship. If this speed is exceeded, a critical

situation may be expected.

1.5.2 Critical situationCritical situations are, for instance:

— damage to cargo tanks with subsequent leakage of, e.g., oil, chemicals, etc— water ingress into dry cargo holds during carriage of particularly valuable or dangerous cargo— damage to fuel oil tanks with subsequent leakage of fuel oil.

The definition of the critical situation will be included in the appendix to the classification certificate.

2 Documentation

2.1 Documentation requirements2.1.1 COLLDocumentation shall be submitted as required by Table 2.

Table 2 Documentation requirements - COLL


Ship hull structure H080 – Strength analysis

Including:

— Collision energy analysis— Critical speed analysis

FI




3.1 General3.1.1 Qualifiers of the COLL notationA qualifier will be assigned according to Table 3 on the basis of the characteristic ratio C* of the criticaldeformation energies as defined in [3.2.8].In special cases COLL notations higher than COLL(6) may be assigned if justified by the design andconstruction of the ship.

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Table 3 COLL-Notation

C* COLL-Notation

2 COLL(1)

3 COLL(2)

4 COLL(3)

6 COLL(4)

10 COLL(5)

20 COLL(6)

3.1.2 Damage stabilityIf wing tanks are arranged in the area to be investigated which shall be assumed as being flooded whereasthe longitudinal bulkheads remain intact, sufficient floatability and stability in such damaged conditions shallbe proved. Longitudinal bulkheads fitted outside the envelope curve of the penetration depths determined forthe collision cases as defined in [3.2.5] shall be considered intact.

3.2 Deformation energy

3.2.1 The deformation energy shall be calculated by procedures recognized by the Society.In case of high-energy-collisions the Minorsky method may be accepted, if the bow and side structures arefound suitable.

Guidance note:On request, the required calculation of deformation energy may be carried out by the Society.


3.2.2 For low-energy-collisions, the Minorsky method does not give sufficiently precise results. Analyses ofthese collisions shall be based on assumptions which take into account the ultimate loads of the bow and sidestructures hitting each other in the area calculated, and their interactions.The computation of ultimate loads shall be based on the assumption of an ideal elastic plastic materialbehaviour. The calculated limit stress RUC to be assumed, is the mean value of the yield strength and thetensile strength, as follows:

The elongation at fracture of the shell shall be taken as 5%.

3.2.3 Ships of approximately equal displacement and with design draughts approximately identical to that ofthe struck ship to be examined shall be assumed as striking ships. 2 bow shapes shall be investigated:

— bow shape 1: raked bow contour without bow bulb— bow shape 2: raked bow contour with bow bulb.

Extremely fully shaped bow configurations shall not be used for the computations.

3.2.4 The computations shall be carried out for an impact at 90°, approximately in the middle between 2transverse bulkheads, making the following assumptions:

— the struck ship remains upright

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— the struck ship has no speed.

3.2.5 Various collision cases shall be investigated for bow shapes 1 and 2, for the strengthened and non-strengthened side structure, covering the design and ballast draughts of the ships involved in the collision.The essential factor for determining the deformation energy are the draught differentials ΔT of the shipsinvolved in the collision, see Figure 1.The following draught differentials shall be considered:

Figure 1 Draught differential ΔT of ships involved in a collision

3.2.6 Based on the deformation energies calculated for the strengthened and non-strengthened sidestructure for the different collision cases defined in [3.2.5] above, the mean values of the critical deformationenergies shall be evaluated by means of weighting factors.

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3.2.7 The mean critical deformation energies shall be determined for the collision cases 1 to 4 and for bothbow shapes by the following formulae:

For bow shape 1:

For bow shape 2:

E01,i = deformation energy, in kJ, for the unstrengthened ship, bow shape 1, collision case i, i = 1 – 4E11,i = deformation energy, in kJ, for the strengthened ship, bow shape 1, collision case i, i = 1 – 4E02,i = deformation energy, in kJ, for the unstrengthened ship, bow shape 2, collision case i, i = 1 – 4E22,i = deformation energy, in kJ, for the strengthened ship, bow shape 2, collision case i, i = 1 – 4.

3.2.8 The ratios of the mean critical deformation energies shall be determined by the following formulae:

The characteristic ratio for the ship is the mean value resulting from the two weighted ratios and in

accordance with the following formula:

3.2.9 The index defined in [3.1.3] will be fixed on the basis of the characteristic ratio C* and thecorresponding minimum value for the critical speed Vcr*,min according to [3.3.3].

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3.3 Critical speed

3.3.1 The critical collision speed Vcr, in knots, shall be determined by the following formula:

Ecr = deformation energy, in kJ, once the critical speed has been reachedm1 = mass, in t, of the striking ship, incl. 10% hydrodynamical added massm2 = mass, in t, of the struck ship, incl. 40% hydrodynamical added mass.

3.3.2 When calculating the critical speeds for the collision cases in accordance with [3.2.5], the draughtsaccording to Table 4 shall be assumed.

Table 4 Draughts of collision cases

Draughts Collision case 1 Collision case 2 Collision case 3 Collision case 4

T1

T1,max T1,max

T2 T2,max T2,max

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3.3.3 For the assignment of a COLL-notation, in addition to the characteristic ratio C* according to Table 3,the minimum values for the mean critical speed Vcr*,min as given in Table 4 shall be met.

Table 5 Minimum values for the mean critical speed vcr*

COLL-Notation Vcr*,min in knots

COLL(1) 1.0

COLL(2) 1.5

COLL(3) 2.5

COLL(4) 4.0

COLL(5) 5.5

COLL(6) 7.0

3.3.4 The mean critical speed results from the weighted critical speeds of collision conditions 1 – 4 for

both bow shapes, in accordance with the following formulae:

V1cri = critical speed, in knots, for bow shape 1, collision case i, i = 1 – 4V2cri = critical speed, in knots, for bow shape 2, collision case i, i = 1 – 4.

The critical speed characteristic for the ship results as mean value from the two weighted speeds and

, in accordance with the following formula:

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SECTION 11 WAVE INDUCED HULL GIRDER VIBRATIONS - WIW

1 General

1.1 IntroductionThe additional class notation WIV (Wave Induced Vibrations),implies an extended strength verificationfocusing on longitudinal structural members by including the effect of wave induced hull girder vibrations,i.e. whipping and springing, representing the additional hull girder response from impact and resonant waveloading.

1.2 ScopeThe class notation WIV (Wave Induced Vibrations) requires additional ultimate strength assessment andfatigue strength assessment to those specified in main class requirements in combination with ship typerequirements given in Pt.5, or CSR. An overall description of the scope is given in Table 1.

Table 1 Calculation scope - WIV

Class notation Ultimate strength Fatigue strength Loads

WIV Cross sectional analysisof the ultimate hull girderstrength

Cross sectional analysis of thefatigue strength of longitudinalstructural members

Still water loads, wave inducedloads, whipping and springing

1.3 ApplicationThe WIV notation is primarily intended for ships where whipping and springing may affect the requirementsto structural design:

— ships with highly optimised scantlings, e.g. ships with high utilization of the hull girder longitudinalstrength according to Pt.3 Ch.5 Sec.3 [2.1.2] or Pt.3 Ch.5 Sec.3 [3.1.2] and/or of the hull girder ultimatestrength according to Pt.3 Ch.5 Sec.4 [2.1.2]

— ship with potentially high service speed, low draught or pronounced bow or stern flare— novel designs— ships with service restrictions, e.g. according to Pt.1 Ch.2 Sec.5.

1.4 Class notationShips built in compliance with the requirements according to this section may be assigned the additionalnotation WIV related to structural strength and integrity as specified in Table 1 and in compliance with therequirements detailed in the following sections for the specific ship type or decided on a case-by-case basisby the Society.

1.5 DefinitionsSymbols and definitions are given in Table 2. For symbols not defined in this section, reference is made toPt.3 Ch.1 Sec.4 [2].

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Table 2 Definitions

Term Definition

Whipping Transient hull girder vibration due to an impact load such as slamming

Springing Resonance hull girder vibration due to wave loads

2 Documentation

2.1 Documentation requirements2.1.1 WIVDocumentation shall be submitted as required by Table 3.

Table 3 Documentation requirements - WIV


H084 – Wave load analysisEstimate of still water and wave bendingmoment with focus on estimating the additionalcontribution from whipping and springing

FI

H082 – Longitudinal strengthanalysis

Focus on ultimate hull girder strength for differentcross sections FIShip hull structure

H085 – Fatigue analysis

Focus on fatigue assessment of details asspecified for the specific ship type in Pt.5 andsensitive to longitudinal loading for different crosssections

FI



3.1 General3.1.1 Recognised computer programThe calculations as required in the following sub-sections shall be carried out by computer programs suppliedby or recognised by the Society. Recognised computer programs are programs applied by builders ordesigners where reliable results have been demonstrated to the satisfaction of the Society.Computer programs for wave load analysis including whipping and springing and their application will bespecially considered.

3.1.2 Recognised testing facilityModel testing as required in the following sub-section shall be carried out by a testing facility which isrecognised by the Society. A recognised testing facility is a testing facility employed by builders or designerswhere reliable results have been demonstrated to the satisfaction of the Society.The model construction, model scale, loading condition, test scope and assessment of the results will bespecially considered.

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3.1.3 Recognised hull monitoring systemWhen hull monitoring is used to obtain data as input to strength calculations a recognised hull monitoringsystem shall be used. A recognised hull monitoring system is a system which has been approved by theSociety for the specific vessel which is used as basis for obtaining the data.When hull monitoring is equipped to the ship and considered for the reduction of partial safety factors forthe ultimate hull girder strength check, a recognised hull monitoring system shall be used. A recognised hullmonitoring system is a system which has been approved by the Society.

3.1.4 Minimum net scantlingsThe net scantlings shall not be less than those determined by the main class requirements in combinationwith ship type requirements given in Pt.5, or by CSR. However, net scantlings obtained by utilising moreadvanced methods like numerical analysis, model tests or available full scale data can be used to replacescantlings based on empirical estimates of whipping and springing.

3.2 Loading conditions3.2.1 Loading conditions for fatigue strength assessmentThe loading conditions for fatigue strength assessment shall be based on the vessel's loading manual andshall represent frequent loading situations representative for most of the operational life time of the vesselwhile at sea.

3.2.2 Loading conditions for ultimate strengthThe loading condition for ultimate strength shall be based on the vessel's loading manual. A severe butfrequent loading condition, i.e. those giving high stress in longitudinal structural members in deck or bottomof the cross sections in the midship area shall be selected.

3.3 Sea statesFor ultimate strength the sea states in North Atlantic shall be used as basis, while for fatigue the sea statesin World Wide trade shall be used as basis.The wave spectrum, wave energy spreading and heading profile shall be taken in accordance with normalpractice for directly calculated rule loads, as specified in the Society's document DNVGL-CG-0130,Hydrodynamic assessment of wave induced loads for ships, or a correction need to be made for the effect ofwave energy spreading and heading profile.If the vessel has a service restriction and is not intended for harsh wave environment like North Atlantic orWorld Wide, the wave environment shall be agreed with the Society on a case-by-case basis.

3.4 SpeedThe speed should not exceed the design speed. Involuntary speed loss needs to be considered to find therealistic speed in these sea states.

3.5 DampingRealistic damping shall be considered in numerical analysis or model tests. The damping considered innumerical analysis or model tests shall be agreed with the Society on a case-by-case basis.

3.6 Extreme loadsThe return period of the extreme whipping event giving the extreme total dynamic moment should be25 years, corresponding to the most probable maximum value and a probability level of exceedance ofapproximately 10-8 per average zero up-crossing period of the bending moment.

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Guidance note:It is important to consider the combination of sea state and speed, because the sea state and speed combination giving the 25 yeardynamic moment (wave + whipping moment) may not correspond to the highest sea state with 25 year return period.


3.7 Target fatigue lifeThe target fatigue life shall be taken as given by Pt.3 Ch.9 Sec.1 [1.4].

3.8 Extreme strength calculationsThe extreme strength in terms of ultimate hull girder strength (or capacity) for a cross section shall becarried out according to requirements determined by the main class requirements in combination withship type requirements given in Pt.5, or by CSR. The procedures and methods are outlined in the Society'sdocument DNVGL-CG-0128, Buckling.Different procedures are associated with different uncertainties and corresponding partial safety factors, γm,shall be used.For the estimate of the hull girder strength without accounting for lateral loads, partial safety factor fordouble bottom, γdb, shall be considered in hogging. This can alternatively be estimated based on directanalysis including lateral loads. In such a case the lateral loads shall correspond to the loads when theextreme total bending moment with whipping is expected.

3.9 Fatigue strength calculationsThe fatigue strength calculations of details sensitive to longitudinal loads shall be carried out according to therequirements determined by the main class requirements in combination with ship type requirements givenin Pt.5, or by CSR. The procedures and methods are outlined in the Society's document DNVGL-CG-0129,Fatigue assessment of ship structures.

4 Ship type requirements

4.1 Container ships4.1.1 GeneralThis section applies to container ships or ships primarily dedicated to carry cargo in containers and operatedin unrestricted service.

4.1.2 Scope for ultimate strength assessmentThe hull girder ultimate strength assessment shall be carried out in way of 0.2L to 0.8L with dueconsiderations given to locations where there are significant changes in hull cross section, e.g. changing offraming system or the fore and aft end of the deck house area in case of two-island designs. Irrespectiveof their location along the ship, in addition, assessments shall be carried out at forward end of the foremostcargo hold and at the transitions of the engine room area to the cargo hold area.

4.1.3 Scope for fatigue assessmentDetails and longitudinal extend for fatigue assessment shall be as defined in Pt.5 Ch.2 Sec.7.

4.1.4 Calculation procedureCalculations should be carried out according to the procedures in the Society's document DNVGL-CG-0153,Fatigue and ultimate strength assessment of container ships including whipping and springing, with empiricalrelations (Level 1) for:

— fvib in the fatigue assessment

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— γwh as partial safety factor for wave induced vibrations in the ultimate strength assessment.

Special considerations are regarded necessary for container ships with one or more of the followingcharacteristics, by using alternative methods based on direct hydrodynamic analysis including whipping andspringing or model tests (Level 2):

— rule length L > 330 m— contract speed V > 25 knots— bow flare angle α > 55°, or— breadth B > 47 m.

Also, full scale measurements on a similar vessel can be used to determine fvib to be used in the fatigueassessment.Results from Level 2 shall replace results from Level 1.

4.2 Other shipsExtent and scope as well as procedure shall be agreed with the Society on a case-by-case basis.

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DNVGL-RU-SHIP-Pt6Ch1 Structural strength and integrity...P a r t 6 C h a p t e r 1 C h a n g e s-c u r r e n t Rules for classification: Ships — DNVGL-RU-SHIP-Pt6Ch1. Edition October

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