Common Structural Rules for
Bulk Carriers, January 2006

Background Document
CHAPTER 4 – DESIGN LOADS

NOTE:- This TB is published to improve the transparency of CSRs and increase theunderstanding of CSRs in the industry.
- The content of the TB is not to be considered as requirements.
- This TB cannot be used to avoid any requirements in CSRs, and in cases
where this TB deviates from the Rules, the Rules have precedence.
- This TB provides the background for the first version (January 2006) of theCSRs, and is not subject to maintenance.

COMMON STRUCTURAL RULES FOR BULK CARRIERS − BACKGROUND DOCUMENT
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COMMON STRUCTURAL RULES FOR BULK CARRIERSCOMMON STRUCTURAL RULES FOR BULK CARRIERS − BACKGROUND DOCUMENT
PAGE 3 – CHAPTER 4: DESIGN LOADSTABLE OF CONTENTS:
SECTION 1 – GENERAL..................................................................................................................... 6
1

GENERAL.................................................................................................................................... 6
1.1 ........................................................................................................................................................ 6

SECTION 2 – SHIP MOTIONS AND ACCELERATIONS................................................................. 7
1

GENERAL.................................................................................................................................... 7
1.1 ........................................................................................................................................................ 7

2

SHIP ABSOLUTE MOTIONS AND ACCELERATIONS ........................................................... 7
2.1
2.2
2.3
2.4
2.5

3

Roll .......................................................................................................................................... 7
Pitch......................................................................................................................................... 8
Heave ...................................................................................................................................... 8
Sway ........................................................................................................................................ 8
Surge ....................................................................................................................................... 8

SHIP RELATIVE ACCELERATIONS ......................................................................................... 9
3.1
3.2

General .................................................................................................................................... 9
Accelerations ........................................................................................................................... 9

SECTION 3 – HULL GIRDER LOADS ............................................................................................. 101

GENERAL.................................................................................................................................. 10
1.1

2

STILL WATER LOADS ............................................................................................................. 10
2.1
2.2
2.3
2.4

3

Sign conventions of bending moments and shear forces ...................................................... 10
General .................................................................................................................................. 10
Still water bending moment .................................................................................................. 10
Still water shear force ............................................................................................................ 11
Still water bending moment and still water shear force in flooded condition ...................... 11WAVE LOADS .......................................................................................................................... 11
3.1
3.2
3.3
3.4

Vertical wave bending moments........................................................................................... 11
Vertical wave shear force ...................................................................................................... 12
Horizontal wave bending moment ....................................................................................... 12
Wave torsional moment ........................................................................................................ 12

SECTION 4 – LOAD CASES ............................................................................................................. 13
1

GENERAL.................................................................................................................................. 13
1.1
1.2

2

Application............................................................................................................................ 13
Equivalent design wave ........................................................................................................ 13

LOAD CASES ............................................................................................................................ 14
2.1
2.2

General .................................................................................................................................. 14
Load combination factors ...................................................................................................... 15

SECTION 5 – EXTERNAL PRESSURES ........................................................................................... 16
1

EXTERNAL PRESSURES ON SIDE SHELL AND BOTTOM .................................................. 16
1.1
1.2
1.3
1.4
1.5

General .................................................................................................................................. 16
Hydrostatic pressure ............................................................................................................. 16
Hydrodynamic pressures for load cases H1, H2, F1 and F2 ................................................. 16
Hydrodynamic pressures for load cases R1 and R2 .............................................................. 16
Hydrodynamic pressure for load cases P1 and P2 ................................................................ 17

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PAGE 4 – CHAPTER 4: DESIGN LOADS

1.6
2

EXTERNAL PRESSURES ON EXPOSED DECKS .................................................................... 17
2.1
2.2
2.3
2.4

3

Exposed decks ....................................................................................................................... 18
Exposed wheel house tops.................................................................................................... 18
Sides of superstructures......................................................................................................... 18
Superstructure end bulkheads and deckhouse walls ............................................................ 18

PRESSURE IN BOW AREA ....................................................................................................... 19
4.1
4.2

5

General .................................................................................................................................. 17
Load cases H1, H2, F1 and F2 ................................................................................................ 17
Load cases R1, R2, P1, and P2................................................................................................ 18
Loads carried on exposed deck ............................................................................................. 18

EXTERNAL PRESSURES ON SUPERSTRUCTURES AND DECKHOUSES .......................... 18
3.1
3.2
3.3
3.4

4

Correction to hydrodynamic pressures ................................................................................. 17

Bow flare area pressure ......................................................................................................... 19
Design bottom slamming pressure........................................................................................ 19

EXTERNAL PRESSURES ON HATCH COVERS ..................................................................... 19
5.1
5.2

General .................................................................................................................................. 19
Wave pressure ....................................................................................................................... 19

SECTION 6 – INTERNAL PRESSURES AND FORCES................................................................... 20
1

LATERAL PRESSURE DUE TO DRY BULK CARGO.............................................................. 20
1.1
1.2
1.3
1.4

2

LATERAL PRESSURE DUE TO LIQUID.................................................................................. 21
2.1
2.2

3

Pressure due to liquid in still water....................................................................................... 21
Inertial pressure due to liquid ............................................................................................... 21

LATERAL PRESSURES AND FORCES IN FLOODED CONDITION .................................... 23
3.1
3.2
3.3
3.4

4

Dry bulk cargo upper surface................................................................................................ 20
Dry bulk cargo pressure in still water ................................................................................... 20
Inertial pressure due to dry bulk cargo ................................................................................. 20
Shear load due to dry bulk cargo........................................................................................... 21

Application ............................................................................................................................ 23
General .................................................................................................................................. 23
Transverse vertically corrugated watertight bulkheads........................................................ 23
Double bottom....................................................................................................................... 24

TESTING LATERAL PRESSURE.............................................................................................. 24
4.1

Still water pressure ................................................................................................................ 24

SECTION 7 – LOADING CONDITIONS ......................................................................................... 25
1

APPLICATION .......................................................................................................................... 25
1.1
1.2

2

GENERAL.................................................................................................................................. 25
2.1
2.2
2.3

3

Ships having a length (L) less than 150 m.............................................................................. 25
Ships having a length (L) of 150 m and above....................................................................... 25
Design loading conditions – General..................................................................................... 25
Applicable ballast conditions ................................................................................................ 26
Departure and arrival conditions .......................................................................................... 26

DESIGN LOADING CONDITIONS FOR LOCAL STRENGTH ............................................. 26
3.1

Definitions ............................................................................................................................. 26

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PAGE 5 – CHAPTER 4: DESIGN LOADS

3.2
3.3
3.4
3.5
3.6
3.7
4

Applicable general conditions............................................................................................... 26
Additional conditions applicable except when additional service feature {no MP} is assigned
26
Additional conditions applicable for BC-A only................................................................... 27
Additional conditions applicable for ballast hold(s) only ..................................................... 27
Additional conditions applicable during loading and unloading in harbour only............... 27
Hold mass curves .................................................................................................................. 27

DESIGN LOADING CONDITIONS FOR DIRECT STRENGTH ANALYSIS ........................ 27
4.1
4.2
4.3

Loading patterns ................................................................................................................... 27
Still water vertical bending moment and shear force............................................................ 28
Application............................................................................................................................ 28

SECTION 8 – LOADING MANUAL AND LOADING INSTRUMENT .......................................... 29
1

GENERAL.................................................................................................................................. 29
1.1
1.2

2

LOADING MANUAL................................................................................................................ 29
2.1
2.2
2.3

3

Definitions ............................................................................................................................. 29
Conditions of approval ......................................................................................................... 30

ANNUAL AND CLASS RENEWAL SURVEY .......................................................................... 30
4.1

5

Definitions ............................................................................................................................. 29
Conditions of approval ......................................................................................................... 29
Language............................................................................................................................... 29

LOADING INSTRUMENT ....................................................................................................... 29
3.1
3.2

4

All ships................................................................................................................................. 29
Ships equal to or greater than 150 m in length (L) ................................................................ 29

General .................................................................................................................................. 30

GUIDANCE FOR LOADING/UNLOADING SEQUENCES.................................................... 30
5.1

General .................................................................................................................................. 30

APPENDIX 1 – HOLD MASS CURVES............................................................................................ 32
1

GENERAL.................................................................................................................................. 32
1.1

2

Application............................................................................................................................ 32

MAXIMUM AND MINIMUM MASSES OF CARGO IN EACH HOLD ................................. 32
2.1
Maximum permissible mass and minimum required masses of single cargo hold in seagoingcondition ........................................................................................................................................... 32
2.2
Maximum permissible mass and minimum required masses of single cargo hold in harbour
condition ........................................................................................................................................... 33

3

MAXIMUM AND MINIMUM MASSES OF CARGO OF TWO ADJACENT HOLDS ........... 33
3.1
Maximum permissible mass and minimum required masses of two adjacent holds inseagoing condition ............................................................................................................................ 33
3.2
Maximum permissible mass and minimum required masses of two adjacent cargo holds inharbour condition.............................................................................................................................. 33

APPENDIX 2 – STANDARD LOADING CONDITION FOR DIRECT STRENGTH ANALYSIS .. 34
APPENDIX 3 – STANDARD LOADING CONDITION FOR FATIGUE ASSESSMENT ............... 35

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PAGE 6 – CHAPTER 4: DESIGN LOADSSECTION 1 – GENERAL
1

GENERAL1.1
1.1.1
1.1.1.aThe design loads in these rules use the equivalent design wave (design regularwave) method described in Section 4.

1.1.1.b

The equivalent design wave method is used for setting design loads including hull
girder loads and normal components of lateral pressure on plate members in waves
and in still water.

1.1.2
1.1.2.a

The loads mentioned below are considered as lateral loads in still water.
(1) External hydrostatic pressure(2) Static pressure due to cargo, ballast and fixed equipment(3) Self weight of hull and outfitting items(4) Set pressures of safety valves (if set)

1.1.2.b

The loads mentioned below are considered as lateral loads in waves.
(1) Wave pressure(2) Dynamic pressure due to inertia of cargo, ballast, fixed equipment(3) Inertia due to hull and outfitting items(4) Dynamic pressure due to slamming of bow flare and bow bottom(5) Dynamic pressure due to green waves

1.1.3
1.1.3.a

Still water vertical shear force and still water vertical bending moment, verticalwave shear force and vertical wave bending moment, horizontal wave bending
moment and wave torsional moment are considered as hull girder loads.

1.1.4
1.1.4.aStresses due to wave induced lateral loads and wave induced hull girder loads are
combined using load combination factors (LCFs) in 8 load cases each specified in
Section 4, 2.2 for the 4 equivalent design waves mentioned in Section 4, 1.2.

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PAGE 7 – CHAPTER 4: DESIGN LOADSSECTION 2 – SHIP MOTIONS AND ACCELERATIONS
1GENERAL1.1
1.1.1
1.1.1.a

Ship motions and accelerations are assumed to vary periodically. The amplitude ofship motions and accelerations calculated from the formulae in this section isassumed as half the amplitude from the peak to the trough. The value
corresponding to an exceedance probability level of 10-8 corresponds to the
maximum ship motion and acceleration that the ship is expected to experience in its
lifetime.

1.1.1.b

The symbols and the acceleration parameter a0, the roll angle θ, the pitch angle φindicated in 2., and other simplified formulae for loads due to waves specified inother sections of this chapter are multiplied by the exceedance probability levelfactor fp, and the value for the strength assessment corresponding to the 10-8 level(such as yield, buckling, ultimate strength) is taken as 1.0, and the value for thestrength assessment (fatigue strength) corresponding to the 10-4 level is taken as 0.5.

1.1.2
1.1.2.a

As an alternative to the formulae in this Section, the Society may accept the valuesof ship motions and accelerations derived from direct calculations or obtained frommodel tests, justified on the basis of the ship’s characteristics and intended service.

1.1.2.b

Generally, the estimated values of ship motions and accelerations by direct load
calculation and model tank tests correspond to exceedance probability levels of 10-8
or 10-4. Wave spectra and long-term wave scatter diagrams used for short-term andlong-term predictions are generally the standard items mentioned below.
(a) Long-term wave scatter diagram: North Atlantic Ocean wave environment(IACS Rec. 34).
(b) Wave spectra: Piersion-Moskowitz type(c) Wave directionality function: cos2

2

SHIP ABSOLUTE MOTIONS AND ACCELERATIONSThe simplified formulae for ship absolute motions and accelerations indicated here
are basically the ones developed by the IACS WD-SL (IACS Wave Data and Sea
Loads) Working Group. The simplified formulae and the acceleration parameters
given here are common to Part CSR-T.

2.1

Roll

2.1.1
2.1.1.a

The roll period TR is the natural period of roll. It is estimated using the radius of
gyration of roll kr and the metacentric height GM in the considered loading
condition.

TR = C

2k r
GM

(s)

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PAGE 8 – CHAPTER 4: DESIGN LOADS

Here, the coefficient C converts the natural period of roll in the atmosphere to thatin water considering added mass, and is taken as 1.1.
2.1.1.b

2.2

The values of radius of gyration of roll kr, and the metacentric height GM, arebasically the values used in the Loading Manual corresponding to the consideredloading condition. If these values have not been derived during the initial design
stage, then the values shown in Table 1, Section 2, Chapter 4 may be used.

Pitch

2.2.1
2.2.1.a

The pitch period TP, is the wave period (or wavelength λ) at which the pitch motion
response function RAO becomes maximum. Pitching motion generally becomesmaximum in the head sea condition.

2.2.1.b

The regular wavelength λ at which the pitch motion response function becomesmaximum is practically the same as the regular wavelength λH at which the verticalwave bending moment at the midship part of the hull specified in Section 4
becomes maximum. Therefore, the same equation given below is used.
⎛

λ = 0.6⎜⎜1 +
⎝

g 2
TLC ⎞
⎟⎟L =
TP (m)
2π
TS ⎠Here, TS is the scantling draft (m), while TLC is the draft (m) at midship in theconsidered loading condition.

2.3

Heave

2.3.1
2.3.1.a2.4

It is considered that for this topic, no information in addition to that shown in theRules, is necessary to explain the background.

Sway

2.4.1
2.4.1.a2.5

It is considered that for this topic, no information in addition to that shown in theRules, is necessary to explain the background.

Surge

2.5.1
2.5.1.a

It is considered that for this topic, no information in addition to that shown in theRules, is necessary to explain the background.

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PAGE 9 – CHAPTER 4: DESIGN LOADS

3SHIP RELATIVE ACCELERATIONS

3.1

General

3.1.1
3.1.1.aTo estimate the dynamic pressures due to inertial forces such as those of cargo andballast, the accelerations in the X (ship's length direction), Y (ship's breadth
direction) and Z (ship’s depth direction) directions at an arbitrary position of thehull (such as at the center of a cargo hold or a tank) should be used.

3.1.1.b

These accelerations consist of accelerations of roll and pitch motions described in 2.,angular acceleration components that arise because of these motions, andaccelerations due to heave, sway, and surge.

3.2

Accelerations

3.2.1
3.2.1.a

The values of the longitudinal acceleration (aX), the transverse acceleration (aY) andthe vertical acceleration (aZ) at any point can be estimated from the formula below
from the absolute values (corresponding to the exceedance probability level) of theship motion and acceleration components described in 3.1, and the load
combination factors described in 2.2 of Section 4, for each loading case of each
equivalent design wave.

aX = C XG g sin Φ + C XS asurge + C XP a pitch x
aY = C YG g sin θ + C YS asway + CYR aroll yaZ = C ZH aheave + C ZR aroll z + C ZP a pitch zHere, CXG ， CXS ， CXP ， CYG ， CYS ， CYR ， CZH ， CZR and CZP are load combination
factors for each loading case of each equivalent design wave specified in Section 4,
Table 3.

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PAGE 10 – CHAPTER 4: DESIGN LOADSSECTION 3 – HULL GIRDER LOADS
1GENERAL

1.1

Sign conventions of bending moments and shear forces

1.1.1
1.1.1.aFor strength analysis and strength assessment, shear forces and bending moments
in still water and in waves acting on the hull as specified in this section must be
considered. The magnitude of the shear forces and bending moments specified inthis section are given as absolute values. The sign conventions of shear forces andbending moments shall be according to the load combination factors of Table 3 ofSection 4, Chapter 4 of the Rules.

2

STILL WATER LOADS

2.1

General

2.1.1
2.1.1.a

Generally, still water shear forces and bending moments used in strength analysis
or strength assessment are used according to each planned loading condition.

2.1.1.b

When studies related to hull girder strength in still water (Chapter 5 of Part CSR-B)
are performed, the maximum value of still water shear force and vertical bending
moment in various intermediate conditions during voyage are used for eachloading condition.

2.1.2

Partially filled ballast tanks in ballast loading conditions

2.1.2.a

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

2.1.3

Partially filled ballast tanks in cargo loading conditions

2.1.3.a

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

2.2

Still water bending moment

2.2.1
2.2.1.a

For the design hogging still water vertical bending moment (MSW,H) and sagging
vertical bending moment (MSW,S) at any transverse section of the hull, the maximum
values at the relevant transverse sections in the hogging and sagging conditions at
the loading condition described in 2.1.1 are used. The designer can also specify alarger still water vertical bending moment and use the same.

2.2.2
2.2.2.a

These formulae are based on IACS UR S7 that specifies the minimum hull girder
section modulus and the IACS UR S11 that specifies the hull girder wave bending
moment and the permissible hull girder stress.

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PAGE 11 – CHAPTER 4: DESIGN LOADS

2.3

Still water shear force

2.3.1
2.3.1.a

2.4

The design still water shear force QSW at any hull transverse section is the maximum
positive value or the maximum negative value of still water shear force at thattransverse section in the loading condition described in 2.1.1. The designer can alsoprescribe a larger still water shear force and use the same.

Still water bending moment and still water shear force in flooded condition

2.4.1
2.4.1.aThe still water shear force in flooded condition QSW,F and the still water verticalbending moment MSW,F (hogging condition and sagging condition) are determinedconsidering the scenario that in each case the cargo hold is independently flooded
up to the water line in the final equilibrium condition during the hull strength
assessment (hull girder ultimate strength assessment of Section, 2, Chapter 5, forinstance) in the flooded condition.

2.4.2
2.4.2.a

The permeability to calculate the mass of flooded water is specified according to theflooded cargo hold and the type of cargo carried.

2.4.3
2.4.3.a

The effects of flooding on the still water vertical bending moment and the still water
shear force need to be studied and quantified during the hull girder strength
assessment.

3

WAVE LOADS

3.1

Vertical wave bending moments

3.1.1

Intact condition

3.1.1.a

The vertical wave bending moment at a hull transverse section in the intact
condition is determined after considering the non-linear phenomena, which areasymmetric in the hogging and sagging conditions due to waves. The vertical wave
bending moment at the exceedance probability level of 10-8 corresponds to the
maximum value of 25 years (design life). The vertical wave bending moment in the
intact condition and the wave shear force in the intact condition specified in 3.2.1
are based on IACS UR S11.

3.1.2

Flooded condition

3.1.2.a

For the vertical wave bending moment in the damaged condition, 0.8 times( {log(108 / 25)} /log 108 ≈ 0.8 ) the maximum vertical wave bending moment in 1 year
(vertical wave bending moment in intact condition) is used.

3.1.3

Harbour conditions

3.1.3.a

The vertical bending moment acting on the hull induced by waves and in thecondition at port is considered to be small compared to the normal voyage
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PAGE 12 – CHAPTER 4: DESIGN LOADS

condition offshore, and thus the value of 0.4 times the vertical wave bending
moment in the intact condition is used.

3.2

Vertical wave shear force

3.2.1

Intact condition

3.2.1.a

The formula in IACS UR S11 is used for the vertical wave shear force that acts on ahull transverse section in the intact condition. Similar to the vertical bending
moment, the vertical wave shear force at the exceedance probability level of 10-8
corresponds to the maximum value of 25 years (design life).

3.2.2

Flooded condition

3.2.2.a

The maximum wave shear force (0.8 times the wave shear force in the intact
condition) in one year is used as the shear force in the damaged condition becauseof the reasons mentioned in 3.1.2.

3.2.3

Harbour conditions

3.2.3.a

The value of 0.4 times the vertical wave shear force in the intact condition is used as
the vertical wave shear force in port because of the reasons mentioned in 3.1.3.

3.3

Horizontal wave bending moment

3.3.1
3.3.1.a

3.4

In addition to the vertical wave bending moment and the vertical wave shear force
that were considered in the assessment of local strength and direct structural
analysis, the horizontal wave bending moment acting on the hull transverse section
induced by waves must also be considered.

Wave torsional moment

3.4.1
3.4.1.a

The wave torsional moment specified in this sub-section is used only in the fatigue
strength assessment of structural members at the hatch corners specified in
Section 5, Chapter 8 of the Rules, and therefore, the value corresponding to theexceedance probability level of 10-4 (fp=0.5 in the formula used) is used. This formulais based on the wave torsional moment of GL Rules.

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PAGE 13 – CHAPTER 4: DESIGN LOADSSECTION 4 – LOAD CASES
1

GENERAL

1.1

Application

1.1.1
1.1.1.a

The load cases described in this section are used in strength analysis and strength
assessment. That is, the load cases are used in local strength analysis for structural
scantlings (plate members, stiffeners, primary supporting members) specified in
Chapter 6 of Part CSR-B, direct strength analysis of structural members (primary
supporting members) specified in Chapter 7, and fatigue assessment of structuraldetails specified in Chapter 8.

1.1.2
1.1.2.a

1.2

For local strength analysis and direct strength analysis, the 8 load cases (H1，H2，
F1 ， F2 ， R1 ， R2 ， P1 and P2) corresponding to four equivalent design waves(design regular waves) specified in 1.2 are considered.

Equivalent design wave

1.2.1
1.2.1.aThe design conditions shown below in the development of design loads are
considered as basic conditions of CSR.
Operating sea area: North Atlantic Ocean (wave data: IACS Rec. No.34）
Design life: Minimum 25 years (exceedance probability: Q=10-8 level)
The technical background described below is mainly for bulk carriers (BC) but it
also includes a part of the results of study on double hull oil tankers.

1.2.1.b

The load components in 1 to 4 below are selected as dominant load components forstructural strength in the Rules.
1. Vertical wave bending moment (head sea)
2. Vertical wave bending moment (following sea)
3. Roll
4. Have pressure at waterline

1.2.1.c

The short-term sea states set for the dominant load conditions of 1 to 4 are proposed
as design sea states. Here, the design sea states are defined as the short-term sea
states that generate the stress values equivalent to the long-term prediction valuesof stresses for structural members of the ship (exceedance probability Q=10-8, All
Headings) .
Short-term sea state according to 1: Design sea state H
Short-term sea state according to 2: Design sea state F
Short-term sea state according to 3: Design sea state R
Short-term sea state according to 4: Design sea state P

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Here, the design sea state H is the short-term sea state at which the verticalacceleration due to the combination of pitching and heaving, and the verticalbending moment generally become maximum The design sea state F is the shortterm sea state similar to the design sea state H, but at which the vertical acceleration
becomes minimum (that is, inertial force due to acceleration becomes minimum).
Also, the design sea state R is the short-term sea state at which the transverse
acceleration due to roll and the hydrodynamic pressure having asymmetric
distribution generally become maximum. Furthermore, the design sea state P is theshort-term sea state at which the hydrodynamic pressure at the waterline of theweather side and the vertical acceleration due to heave generally become maximum.

2

LOAD CASES

2.1

General

2.1.1
2.1.1.aTwo load cases exist for each equivalent design wave. That is, the cases are thewave trough case (H1 or F1) and the wave crest case (H2 or F2) corresponding to theequivalent design waves H and F, the weather side (port) Down case (R1 or P1) andthe weather side (port) Up case (R2 or P2) corresponding to the equivalent design
waves R and P.

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PAGE 15 – CHAPTER 4: DESIGN LOADS

2.1.1.b

2.2

Moreover, if the hull structure or the cargo loading is not symmetric with respect tothe hull center line, in addition to the beam sea load cases (R1, R2, P1 and P2)
mentioned above, additional four load cases must also be assessed for strength.

Load combination factors

2.2.1
2.2.1.aLoad combination factor (LCF) is specified by using the response function of load
component (RAO) and dominant load components for each WDW (H, F, R and P).

2.2.2
2.2.2.a

In addition to considering hull girder loads in waves corresponding to load
combination cases mentioned in 2.1, the still water bending moment mentioned in
2.2 of Section 3 also needs to be considered in the structural analysis.

2.2.3
2.2.3.a

In addition to the external pressure specified in Section 5, static pressures or staticforces due to loading (including ballast) including deck loading, or inertialpressures or inertial forces acting on loading (including ballast) induced byaccelerations should be considered for the internal loads used in structural analysis.

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PAGE 16 – CHAPTER 4: DESIGN LOADSSECTION 5 – EXTERNAL PRESSURES
1

EXTERNAL PRESSURES ON SIDE SHELL AND BOTTOM

1.1

General

1.1.1
1.1.1.aExternal pressure used for strength assessment and structural analysis is the totalpressure (p) equal to the sum of the hydrostatic pressure (pS) at the position of themember being examined and the wave pressure (pW).

1.1.1.b

The wave pressure may be a negative pressure as explained in 1.3, 1.4, and 1.5.
However, the total pressure (p) is not to be taken as a negative value.

1.1.1.c

The maximum value from the simplified formulae specified in 1.3, 1.4, and 1.5 isassigned a value equivalent to the maximum value of wave pressure (long-term
prediction value corresponding to the exceedance probability level of 10-8).

1.2

Hydrostatic pressure

1.2.1
1.2.1.a

1.3

The hydrostatic pressure equivalent to static pressure in various loading conditions
to be studied in still water is considered.

Hydrodynamic pressures for load cases H1, H2, F1 and F2

1.3.1
1.3.1.aThe distribution of wave pressure corresponding to 4 load cases (H1, H2, F1, and
F2) is the distribution in equivalent design waves H and F at which vertical wave
bending becomes maximum. The wave pressure is obtained by multiplying the
response function RAO of wave pressure in equivalent design wave at which thevertical wave bending moment at midship specified in Section 4 becomes maximum,by the regular wave height of equivalent design wave of the corresponding
dominant load component.

1.3.1.b

The wavelength at which the amplitude of the wave pressure at the centerline ofmidship generated in head seas becomes maximum is practically the same as the
wavelength when the vertical wave bending moment becomes maximum. When the
wave pressure at the centerline of midship becomes maximum, the wave pressure
at another location in the same cross section also becomes nearly maximum, and thephase is almost the same.

1.3.1.c

The nonlinear influence coefficient of 0.9 is considered based on the results of modeltank tests for the wave pressure for load cases H1, H2, F1, and F2 at the exceedance
probability level of 10-8.

1.4

Hydrodynamic pressures for load cases R1 and R2

1.4.1
1.4.1.aThe distribution of wave pressure for load cases R1 and R2 is the distribution inequivalent design wave R at which the rolling ship motion becomes maximum.
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PAGE 17 – CHAPTER 4: DESIGN LOADS

1.4.1.b

The distribution of wave pressure comprises the fluctuating part of the hydrostaticpressure from the roll angle (asymmetric component; first term of the formulaspecified in 1.4.1, Sec. 5, Ch. 4 of the Rules) and the fluctuating part due to heave(asymmetric part; 2nd term of the formula above).

1.4.1.cA nonlinear influence coefficient of 0.8 is considered for the wave pressure for loadcases R1 and R2 at the exceedance probability level of 10-8.

1.5

Hydrodynamic pressure for load cases P1 and P2

1.5.1
1.5.1.aThe distribution of wave pressure for load cases P1 and P2 is the distribution ofequivalent design wave P at which the wave pressure at midship becomesmaximum.

1.5.1.b

A nonlinear influence coefficient of 0.65 is considered for the wave pressure for loadcases P1 and P2 at the exceedance probability level of 10-8.

1.6

Correction to hydrodynamic pressures

1.6.1
1.6.1.a

When the wave pressure at the waterline becomes positive (load cases H1, H2, F2,
R1, R2 and P1), the wave pressure at the waterline is converted to head of sea waterand the wave pressure above the waterline is assumed to occur linearly (inclinationof 45 degrees) up to the converted water head position.

1.6.1.b

When the wave pressure at the waterline becomes negative (load cases H1, H2, F1,
R1, R2 and P2), the wave pressure below the waterline is taken as the sum of the
wave pressure and the hydrostatic pressure that does not become negative.

2

EXTERNAL PRESSURES ON EXPOSED DECKS

2.1

General

2.1.1
2.1.1.a

2.2

The pressures specified in 2.2 and 2.3 must be considered regardless of the existenceof water breakers installed on the exposed deck.

Load cases H1, H2, F1 and F2

2.2.1
2.2.1.a

The external pressure pD, at any point on the exposed deck for load cases H1, H2, F1
and F2 in head seas and following seas is estimated by the pressure (pW) acting on
the exposed deck specified in the LL Convention (or IACS UR S21) and the pressure
coefficient φ for the exposed deck (φ, coefficient depending on height of deck
which becomes smaller as the height of deck increases).

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PAGE 18 – CHAPTER 4: DESIGN LOADS

2.3

Load cases R1, R2, P1, and P2

2.3.1
2.3.1.a

The external pressure pD at any point on the exposed deck for load cases R1, R2, P1
and P2 in beam seas is estimated using the wave pressure at the side shell positionon the exposed deck described in 1.4, 1.5, and 1.6 (the larger of the values from theport side and the starboard side is taken), the pressure coefficient (φ) at the exposed
deck and the considered position z.

2.4

Loads carried on exposed deck

2.4.1

Pressure due to distributed load

2.4.1.a

When the exposed deck is loaded with distributed cargo load (such as lumber, etc.),
the static and dynamic loads due to such cargo should be considered.

2.4.2

Concentrated forces due to unit load

2.4.2.a

When unit load is carried on the exposed deck (such as outfitting items), the staticand dynamic forces due to this unit load must be considered.

3

EXTERNAL PRESSURES ON SUPERSTRUCTURES AND DECKHOUSES

3.1

Exposed decks

3.1.1
3.1.1.a

3.2

External pressures on exposed deck specified in 2also apply to the exposed decks ofsuperstructure and deckhouses. However, the external pressures and thosespecified in 3.2, 3.3, and 3.4 apply only to the scantling requirements of members
specified in Section 4, Chapter 9.

Exposed wheel house tops

3.2.1
3.2.1.a

3.3

The pressure p acting on the tops of exposed wheelhouse is taken as 2.5 kN/m2 andgreater.

Sides of superstructures

3.3.1
3.3.1.a

3.4

The pressure acting on the sides of superstructure is estimated according to thelongitudinal position and height of the location in the superstructure.

Superstructure end bulkheads and deckhouse walls

3.4.1
3.4.1.a

The pressure acting on the superstructure bulkheads and deckhouse walls is
calculated according to the longitudinal position and height on the bulkhead (wall).

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PAGE 19 – CHAPTER 4: DESIGN LOADS

4

PRESSURE IN BOW AREA

4.1

Bow flare area pressure

4.1.1
4.1.1.aThis calculation formula has been corrected to attain consistency with GL Rules
calculation formula that assumes the sea conditions in CSR.
This slamming pressure is applicable only to the scantling requirements of members
specified in 4., Section 1, Chapter 9.

4.2

Design bottom slamming pressure

4.2.1
4.2.1.aThis slamming pressure is applicable only to the scantling requirements of specified
members. This calculation formula has been corrected to attain consistency with the
GL Rules calculation formula that assumes the sea conditions in CSR.

4.2.2
4.2.2.aTo limit the slamming loads at acceptable level, the smallest design ballast draught
at forward perpendicular should only be undercut in cases where bottom slamming
is not expected.

5

EXTERNAL PRESSURES ON HATCH COVERS

5.1

General

5.1.1
5.1.1.a

5.2

When cargo is loaded on hatch covers, the static and dynamic loads due to theloaded cargo are specified in 2.5 according to the type of cargo.

Wave pressure

5.2.1
5.2.1.a

The wave pressure on hatch covers is basically estimated by calculating the pressure
acting on the exposed deck specified in 2.2.1 (according to the regulations of the LL
Convention or IACS UR S21). This wave pressure is applicable only to scantling
requirements of members of hatch covers specified in 4., Section 5, Chapter 9.

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PAGE 20 – CHAPTER 4: DESIGN LOADSSECTION 6 – INTERNAL PRESSURES AND FORCES
1

LATERAL PRESSURE DUE TO DRY BULK CARGO

1.1

Dry bulk cargo upper surface

1.1.1
1.1.1.a

When cargo of small density (ρC) is carried and the shape of the surface of the cargoreaches the upper end of the hatch coaming, the upper surface of the bulk cargoshould be taken ignoring the topside tanks, based on practicality and safety andtaking into account the friction effects between the cargo and the wall surfaces.

1.1.1.b

The height of surface contour of loaded cargo (hC, vertical distance from the inner
bottom plating to the assumed bulk cargo upper surface) is determined assuming
loaded condition with width equal to the width between side shell plating or
longitudinal bulkheads surrounding the cargo in the cargo hold considering anequivalent volume of cargo.

1.1.2
1.1.2.a

1.2

When cargo of high density such as iron ore is loaded in the cargo hold, the uppersurface of the cargo does not reach the position of the upper deck. To set the cargopressure applied on the inner bottom plating on the safe side, the height of the
shape of the surface of cargo (hC) should be set assuming that the volume and mass(M) of the cargo remain unchanged, the upper surface of the cargo is considered ashaving a plane surface of width BH/2 on the centerline (BH is the mean width of the
cargo hold), and the shape of the cargo has inclined parts with an angle equal to half
the angle of repose (ψ/2) at sides.

Dry bulk cargo pressure in still water

1.2.1
1.2.1.a

1.3

The static pressure due to grain cargo is estimated from the position of the location
to be studied, the height of the shape of the surface of loaded cargo (hC), and thecoefficient KC (KC=cos2α + K0sin2α) which takes the coefficient of earth pressure atrest K0, and the angle of the slant plate as parameters.

Inertial pressure due to dry bulk cargo

1.3.1
1.3.1.aThe dynamic pressure due to inertial force of the grain cargo can be estimated by
the position of the location to be studied, the height of the shape of the surface ofloaded cargo (hC), the coefficient KC, and the longitudinal, transverse and verticalaccelerations at the center of gravity of the cargo hold specified in 3., Section 2,
Chapter 4, for the load cases (H1, H2, F1, F2, R1, R2, P1 and P2) specified in 2,
Section 4, Chapter 4.

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PAGE 21 – CHAPTER 4: DESIGN LOADS

1.4

Shear load due to dry bulk cargo

1.4.1
1.4.1.a

To consider a balance between the overall internal pressure or force (gravity andinertial force due to vertical acceleration) in the vertical direction of the FE
structural model in direct structural analysis, shear load according to the calculation
formula shown in 1.4.1 should be considered in addition to the static internalpressure and dynamic internal pressure according to the calculation formula shownin 1.2.1 and 1.3.1.

1.4.2
1.4.2.a

Only inertial forces due to longitudinal and transverse accelerations exist in thelongitudinal and transverse directions of the ship because of basically the same
reasons as in 1.4.1, and therefore, shear load is applied on the inner bottom plating
to consider the balance of overall forces (inertial force due to acceleration) in thelongitudinal and transverse directions of the FE structural model. The shear load isconsidered only for direct structural analysis.

2

LATERAL PRESSURE DUE TO LIQUID

2.1

Pressure due to liquid in still water

2.1.1
2.1.1.aPressure due to liquid in still water is calculated based on the head of liquid
including the height of air pipe, in principle. The setting pressure is to be consideredwhen a safety valve is provided. Also, the pressure due to liquid in still water istaken as 25 kN/m2 or greater for assessment of local strength.

2.1.2
2.1.2.a

2.2

If ballast water exchange is scheduled by the flow-through method, the pressure
due to liquid in still water is taken as 25 kN/m2 and greater for direct strength
analysis specified in Chapter 7 and for local strength assessment. To generate ahigher pressure by design of piping and pumps, high pressure needs to beconsidered.

Inertial pressure due to liquid

2.2.1
2.2.1.a

The internal dynamic pressure due to liquid can be estimated for general load cases(H1, H2, F1, F2, R1, R2, P1 and P2) by multiplying the longitudinal, transverse andvertical accelerations at the centerline of cargo holds or tanks by the distance fromthe reference point to the assessment point.

2.2.1.bFig. 3.1(a) and (b) show the dynamic internal pressure distributions due tolongitudinal and vertical accelerations respectively for load case H1. Also, Fig. 3.2(a) and (b) show the dynamic internal pressure distributions due to transverse andvertical accelerations respectively in load cases R1 or P1. Furthermore, Fig. 3.2(c)shows the combined dynamic internal pressure distribution due to transverse andvertical accelerations.
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PAGE 22 – CHAPTER 4: DESIGN LOADS

stern

bow

aX

(a) Dynamic internal pressure distribution due to aportside

starboardaZ(b) Dynamic internal pressure distribution due to az
Fig. 3.1 Dynamic internal pressure distributions due to longitudinal and verticalaccelerations for load case H1

portside

starboardaY+(a) Dynamic internal pressure distribution due to aY
portside

starboardaZ=(b) Dynamic internal pressure distribution due to aZ
portside

starboardaZaY(c) Dynamic internal pressure distribution due to the combination of accelerations aYand aZ
Fig. 3.2 Dynamic internal pressure distribution due to transverse acceleration (aY), verticalacceleration (aZ) and the combination of aY and aZ in load case R1 or P1

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PAGE 23 – CHAPTER 4: DESIGN LOADS3LATERAL PRESSURES AND FORCES IN FLOODED CONDITION

3.1

Application

3.1.1
3.1.1.a

3.2

Regulations for pressure in the general case are shown in 3.2, those for the special
case of corrugated transverse bulkhead are shown in 3.3 and those for the special
case of double bottom are shown in 3.4 in the flooded condition, according to themembers studied.

General

3.2.1
3.2.1.a

Structural members corresponding to the general case are plate members that form
the boundaries of compartments in which liquid is not carried except inner bottom
plating and side shell. The pressure applied on these plate members can be
estimated from the formula specified in 3.2.1, Section 6, Chapter 4.

3.3

Transverse vertically corrugated watertight bulkheads

3.3.1

Application

3.3.1.a

The regulation is in accordance with the regulation of IACS UR S18. For each cargohold, the flooded condition is considered independently.

3.3.2

General3.3.2.a

The regulation is in accordance with the regulation of IACS UR S18.

3.3.3

Flooding level3.3.3.a

The regulation is in accordance with the regulation of IACS UR S18.

3.3.4

Pressures and forces on a corrugation in non-flooded bulk cargo loaded
holds

3.3.4.a

The regulation is in accordance with the regulation of IACS UR S18.

3.3.5

Pressures and forces on a corrugation in flooded bulk cargo loaded holds

3.3.5.a

The regulation is in accordance with the regulation of IACS UR S18.

3.3.6

Pressures and forces on a corrugation in flooded empty holds

3.3.6.a

The regulation is in accordance with the regulation of IACS UR S18.

3.3.7

Resultant pressure and forces

3.3.7.a

The regulation is in accordance with the regulation of IACS UR S18.

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PAGE 24 – CHAPTER 4: DESIGN LOADS

3.4

Double bottom

3.4.1

Application

3.4.1.a

The regulation is based on the regulation of IACS UR S20. For each cargo hold, theflooded condition is considered independently.

3.4.2

General3.4.2.a

The regulation is based on the regulation of IACS UR S20.

3.4.3

Flooding level

3.4.3.a

The regulation is based on the regulation of IACS UR S20.

4TESTING LATERAL PRESSURE

4.1

Still water pressure

4.1.1
4.1.1.aDuring local strength assessment of plate members and stiffeners for whichhydrostatic testing is required, the still water pressure due to the hydrostatic test is
estimated from the water head of the hydrostatic test, and compartments andpositions of structural members.

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PAGE 25 – CHAPTER 4: DESIGN LOADSSECTION 7 – LOADING CONDITIONS1APPLICATION

1.1

Ships having a length (L) less than 150 m

1.1.1
1.1.1.a

1.2

IACS UR S25 is a regulation applicable to bulk carriers of 150 m and greater inlength. For bulk carriers under 150 m in length, the requirement is to design basedon the loading conditions actually assumed regardless of the requirements of IACS
UR S25.

Ships having a length (L) of 150 m and above

1.2.1
1.2.1.aThis regulation is in accordance with IACS UR S25.

1.2.2
1.2.2.aThis regulation is in accordance with IACS UR S25.

1.2.3
1.2.3.aThis regulation is in accordance with IACS UR S25.

1.2.4
1.2.4.aThis regulation is in accordance with IACS UR S25.

1.2.5
1.2.5.aThis regulation is in accordance with IACS UR S25.

2

GENERAL

2.1

Design loading conditions – General

2.1.1
2.1.1.aThis regulation is in accordance with IACS UR S25.

2.1.2

BC-C

2.1.2.aThis regulation is in accordance with IACS UR S25.

2.1.3

BC-B

2.1.3.aThis regulation is in accordance with IACS UR S25.

2.1.4

BC-A

2.1.4.aThis regulation is in accordance with IACS UR S25.

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PAGE 26 – CHAPTER 4: DESIGN LOADS

2.2

Applicable ballast conditions

2.2.1

Ballast tank capacity and disposition

2.2.1.aThis regulation is in accordance with IACS UR S25.

2.2.2

Strength requirements

2.2.2.aThis regulation is in accordance with IACS UR S25.

2.3

Departure and arrival conditions

2.3.1
2.3.1.aThis regulation is in accordance with IACS UR S25.

3

DESIGN LOADING CONDITIONS FOR LOCAL STRENGTH

3.1

Definitions

3.1.1
3.1.1.a

3.2

This regulation is in accordance with IACS UR S25.

Applicable general conditions

3.2.1
3.2.1.aThis regulation is in accordance with IACS UR S25.

3.2.2
3.2.2.aThis regulation is in accordance with IACS UR S25.

3.2.3
3.2.3.a

3.3This regulation is in accordance with IACS UR S25.

Additional conditions applicable except when additional service feature {noMP} is assigned

3.3.1
3.3.1.aThis regulation is in accordance with IACS UR S25.

3.3.2
3.3.2.aThis regulation is in accordance with IACS UR S25.

3.3.3
3.3.3.aThis regulation is in accordance with IACS UR S25.

3.3.4
3.3.4.aThis regulation is in accordance with IACS UR S25.

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PAGE 27 – CHAPTER 4: DESIGN LOADS

3.4

Additional conditions applicable for BC-A only

3.4.1
3.4.1.aThis regulation is in accordance with IACS UR S25.

3.4.2
3.4.2.aThis regulation is in accordance with IACS UR S25.

3.4.3
3.4.3.a

3.5This regulation is in accordance with IACS UR S25.

Additional conditions applicable for ballast hold(s) only

3.5.1
3.5.1.a

3.6This regulation is in accordance with IACS UR S25.

Additional conditions applicable during loading and unloading in harbour
only

3.6.1
3.6.1.aThis regulation is in accordance with IACS UR S25.

3.6.2
3.6.2.aThis regulation is in accordance with IACS UR S25.

3.6.3
3.6.3.a

3.7This regulation is in accordance with IACS UR S25.

Hold mass curves

3.7.1
3.7.1.aThis regulation is in accordance with IACS UR S25.

3.7.2
3.7.2.aThis regulation is in accordance with IACS UR S25.

4

DESIGN LOADING CONDITIONS FOR DIRECT STRENGTH ANALYSIS

4.1

Loading patterns

4.1.1
4.1.1.aLoading conditions to be considered in direct strength analysis are categorized bytype of ship (by notation) summarized in Table 1 of the Rules.

4.1.2
4.1.2.a

Separate considerations are necessary for special loading.

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PAGE 28 – CHAPTER 4: DESIGN LOADS

4.2

Still water vertical bending moment and shear force

4.2.1
4.2.1.a

The loading conditions and load cases (design wave) are combined in direct
strength analysis, but in this case, the still water vertical bending moment to beconsidered is specified in Table 2 of the Rules. Basically, from the permissible
hogging and sagging values, those values that yield more severe results for theassumed loading conditions, or both are to be considered. However, still watervertical bending moments that do not normally occur are exempted. Moreover, stillwater vertical bending moment in the homogenous loading condition is taken as
50% of the permissible value. As specified in Table 3 of the Rules, the permissible
still water vertical shear force needs to be considered in shear force analysis, but theloading conditions for which analysis is to be performed were restricted to those inwhich high shear forces occur, such as the alternate loading condition. Also, only
the H and F load cases corresponding to the head seas and following seas
respectively, were considered.

4.2.2
4.2.2.a

4.3

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

Application

4.3.1
4.3.1.a

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

4.3.2
4.3.2.a

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

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PAGE 29 – CHAPTER 4: DESIGN LOADSSECTION 8 – LOADING MANUAL AND LOADINGINSTRUMENT
1

GENERAL

1.1

All ships

1.1.1
1.1.1.a

1.2

The regulation is based on IACS UR S1 and S2.

Ships equal to or greater than 150 m in length (L)

1.2.1
1.2.1.a

The regulation is based on IACS UR S1 and S2.

2

LOADING MANUAL

2.1

Definitions

2.1.1

All ships

2.1.1.a

The regulation is based on IACS UR S1 and S2.

2.1.2

Ships equal to or greater than 150 m in length (L)2.1.2.a

The regulation is based on IACS UR S1 and S2.

2.2

Conditions of approval

2.2.1

All ships

2.2.1.a

The regulation is based on IACS UR S1 and S2.

2.2.2

Ships equal to or greater than 150 m in length (L)2.2.2.a

The regulation is based on IACS UR S1 and S2.

2.3

Language

2.3.1
2.3.1.a

The regulation is based on IACS UR S1 and S2.

3

LOADING INSTRUMENT

3.1

Definitions

3.1.1

All ships

3.1.1.a

The regulation is based on IACS UR S1 and S2.

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PAGE 30 – CHAPTER 4: DESIGN LOADS

3.1.2

Ships equal to or greater than 150 m in length (L)

3.1.2.a

The regulation is based on IACS UR S1 and S2.

3.2

Conditions of approval

3.2.1

All ships

3.2.1.a

The regulation is based on IACS UR S1 and S2.

3.2.2

Ships equal to or greater than 150 m in length (L)

3.2.2.a

The regulation is based on IACS UR S1 and S2.

3.2.3
3.2.3.a

The regulation is based on IACS UR S1 and S2.

3.2.4
3.2.4.a

The regulation is based on IACS UR S1 and S2.

3.2.5
3.2.5.a

The regulation is based on IACS UR S1 and S2.

4

ANNUAL AND CLASS RENEWAL SURVEY

4.1

General

4.1.1
4.1.1.a

The regulation is based on IACS UR S1 and S2.

4.1.2
4.1.2.a

The regulation is based on IACS UR S1 and S2.

4.1.3
4.1.3.a

The regulation is based on IACS UR S1 and S2.

5GUIDANCE FOR LOADING/UNLOADING SEQUENCES

5.1

General

5.1.1
5.1.1.a

The regulation is based on IACS UR S1 and S2.

5.1.2
5.1.2.a

The regulation is based on IACS UR S1 and S2.

5.1.3
5.1.3.a

The regulation is based on IACS UR S1 and S2.

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PAGE 31 – CHAPTER 4: DESIGN LOADS

5.1.4
5.1.4.a

The regulation is based on IACS UR S1 and S2.

5.1.5
5.1.5.a

The regulation is based on IACS UR S1 and S2.

5.1.6
5.1.6.a

The regulation is based on IACS UR S1 and S2.

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PAGE 32 – CHAPTER 4: DESIGN LOADSAPPENDIX 1 – HOLD MASS CURVES
1

GENERAL

1.1

Application

1.1.1
1.1.1.a

CSR for Bulk Carriers is applicable to typical bulk carriers with topside tanks andbilge hopper tanks. For these ships of length 150 m and greater, class notations "BCA," "BC-B," or "BC-C" may be assigned according to the regulations of 3.1, Section 1,
Chapter 1.

1.1.2
1.1.2.a

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

1.1.3
1.1.3.a

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

1.1.4
1.1.4.a

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

2

MAXIMUM AND MINIMUM MASSES OF CARGO IN EACH HOLD

2.1

Maximum permissible mass and minimum required masses of single cargohold in seagoing condition

2.1.1

General2.1.1.a

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

2.1.2

BC-A ship

2.1.2.a

The examples of hold mass curves for BC-A ships covered by the standard loading
conditions in Chapter 4 Section 7 are described in this paragraph.

2.1.3

BC-A ship with {No MP}

2.1.3.a

The examples of hold mass curves for BC-A ships with {No MP} covered by thestandard loading conditions in Chapter 4 Section 7 are described in this paragraph.

2.1.4

BC-B and BC-C ships

2.1.4.a

The examples of hold mass curves for BC-B and BC-C ships covered by the standard
loading conditions in Chapter 4 Section 7 are described in this paragraph.

COMMON STRUCTURAL RULES FOR BULK CARRIERSCOMMON STRUCTURAL RULES FOR BULK CARRIERS − BACKGROUND DOCUMENT
PAGE 33 – CHAPTER 4: DESIGN LOADS

2.1.5

BC-B and BC-C ships with {No MP}

2.1.5.a

The examples of hold mass curves for BC-B and BC-C ships with {No MP} coveredby the standard loading conditions in Chapter 4 Section 7 are described in thisparagraph.

2.2

Maximum permissible mass and minimum required masses of single cargohold in harbour condition

2.2.1

General2.2.1.a

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

2.2.2

All ships

2.2.2.a

The examples of hold mass curves for all ships covered by the standard loading
conditions in Chapter 4 Section 7 are described in this paragraph.

3

MAXIMUM AND MINIMUM MASSES OF CARGO OF TWO ADJACENT
HOLDS

3.1

Maximum permissible mass and minimum required masses of two adjacent
holds in seagoing condition

3.1.1

General3.1.1.a

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

3.1.2

BC-A ships

3.1.2.a

The examples of hold mass curves for BC-A ships covered by the standard loading
conditions in Chapter 4 Section 7 are described in this paragraph.

3.1.3

BC-B and BC-C ships

3.1.3.a

The examples of hold mass curves for BC-B and BC-C ships covered by the standard
loading conditions in Chapter 4 Section 7 are described in this paragraph

3.2

Maximum permissible mass and minimum required masses of two adjacentcargo holds in harbour condition

3.2.1

General3.2.1.a

It is considered that for this topic, no information in addition to that shown in theRules is necessary to explain the background.

3.2.2

All ships

3.2.2.a

The examples of hold mass curves for all ships covered by the standard loading
conditions in Chapter 4 Section 7 are described in this paragraph.

COMMON STRUCTURAL RULES FOR BULK CARRIERSCOMMON STRUCTURAL RULES FOR BULK CARRIERS − BACKGROUND DOCUMENT
PAGE 34 – CHAPTER 4: DESIGN LOADSAPPENDIX 2 – STANDARD LOADING CONDITION FOR
DIRECT STRENGTH ANALYSIS
Regulations related to loading conditions, drafts, load cases, still water vertical bending
moment and so on, to be considered for direct strength calculation are given in Section 7,
Chapter 4 of the Rules. Details of these requirements, however, are summarized inAppendix 2. The loading conditions assumed were denoted using figures, and the drafts,
load cases, still water vertical bending moment and so on, were also summarized together
for the convenience of designers. From the results of test calculations, load cases that were
determined as dominant were specified.

COMMON STRUCTURAL RULES FOR BULK CARRIERSCOMMON STRUCTURAL RULES FOR BULK CARRIERS − BACKGROUND DOCUMENT
PAGE 35 – CHAPTER 4: DESIGN LOADSAPPENDIX 3 – STANDARD LOADING CONDITION FOR
FATIGUE ASSESSMENT
Regulations related to loading conditions and load cases to be assumed in direct strength
calculation implemented for fatigue strength assessment are specified in Section 1, Chapter 8of the Rules. Further details of these requirements are summarized in Appendix 3 of theRules.

COMMON STRUCTURAL RULES FOR BULK CARRIERS