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Rules for Building and Classing

Bulk Carriers for Service on the Great Lakes

1978

American Bureau of Shipping Incorporated by Act of the Legislature of the State of New York 1862

Copyright © 1978 American Bureau of Shipping Two World Trade Center 106th Floor New York, N.Y. 10048, U.S.A.

Third printing August, 1995

American Bureau of Shipping


Bulk Carriers for Service on The Great Lakes

1978

Notice No. 1

At the meeting of the Technical Committee held held 14 November 1990 the following changes were approved and become effective 14 May 1991 unless another date is given.

Rule Changes

Section 2 Longitudinal Strength Section 8 Decks

New sub-paragraph 2.2.2d and new subsection 8.9 added as follows to require that long hatch coamings be properly stiffened and section modulus calculated accordingly in-line with the Steel Vessel Rules.

2.2.2.d Section Modulus With Continuous Coaming

Where longitudinal coamings of length greater than 0.14L are provided, they are to comply with the requirements of 8.9. Such continuous coam-ings may be included in the calculation of hull girder inertia which is to be divided by the sum of the distance from neutral axis to deck at side and the height of continuous hatch coaming, to obtain the section modulus to the top of the coaming.

8.9 Continuous Longitudinal Hatch Coamings

Where longitudinal hatch coamings of length greater than 0.141, are sup-ported by longitudinal bulkheads or deep girders, they are in general to be longitudinally stiffened. The coaming plates and stiffeners are to have scant-lings as required for decks. Special consideration will be given where calcula-tions are submitted to show adequate buckling strength in the maximum expected sagging conditions.

Section 2 Longitudinal Strength

Title changed as subsection 2.4 revised and expanded to require that a loading manual be provided on all vessels and that where a loading instru-ment is also installed, it is to be checked for accuracy at regular intervals.

2.4 Loading Guidance

A loading manual based on still-water bending conditions is to be provided on all vessels and submitted for review. This manual is to show the effect of the various loaded and ballasted conditions upon the longitudinal bend-ing. The loading manual is to indicate the still-water bending moments at amidships and at other locations along the length of the vessel as necessary.

A loading instrument where installed is to be of a type suitable for the in-tended service. The check conditions and other relevant data are to be sub-mitted for review. The accuracy of the loading instrument is to be checked at regular intervals by applying approved test loading conditions. In the event the loading instrument malfunctions, the loading manual is to be us-ed, for assessing the suitability of the intended loading condition.

—2—

Contents

Sections 1 General 2 Longitudinal Strength 3 Bottom Structure 4 Shell Plating 5 Framing 6 Watertight Bulkhe,,ls 7 Tank Boundary Bulkheads 8 Decks 9 Superstructures and Deckhouses

10 Equipment 11 Tables of nliocs

Appendices

A Calculation of Shear Stresses B Load Line Markings C Publications D Bureau Offices

Index

American Bureau of Shipping


Bulk Carriers for Service on The Great Lakes

1978

Notice No. 2

At the meeting of the Technical Committee held 9 November 1995 the following changes were approved and become effective 9 May 1996 unless another date is given.

Rule Changes

SECTION 12 PROTECTION OF DECK OPENINGS (1996)

(A new Section 12 added as shown below.)

12.1 General

All openings in decks are to be framed to provide efficient support and attachment to the ends of the deck beams. The proposed arrangements and details for all hatchways are to be submitted for approval.

12.2 Position of Deck Openings

For the purpose of the Rules, two positions of deck openings are defined as follows:

Position 1

Upon exposed freeboard decks, and upon exposed superstructure decks or a trunk deck situated forward of a point located a quarter of the vessel's length from the forward perpendicular.

Position 2 Upon exposed superstructure decks or trunk of at least standard* height and situated abaft a quarter of the vessel's length from the forward perpendicular.

* Standard height as defined in Load Line Regulations for Great Lakes Vessels

12.3 Hatchway Coamings

12.3.1 Height of Coamings The height of coamings of hatchways secured weathertight by tarpaulins and battening devices is to be at least as follows:

18.0 in, (457 mm) if in Position 1 12.0 in. (305 mm) if in Position 2

Where hatch covers are made of steel or other equivalent material and made tight by means of gaskets and clamping devices, these heights may be reduced, or the coamings omitted entirely, provided that the safety of the vessel is not thereby impaired in any sea condition.

12.3.2 Coaming Plates Coaming plates are to be of steel or equivalent material and not less than 0.375 in. (9.5 mm) thick.

12.3.3 Coaming Stiffening Efficient brackets or stays are to be fitted from the upper edge of the coaming to the deck at intervals of not more than 10 ft (3 m). All exposed coamings other than Position 1 which are 30 in. (760 mm) or more in height are to be similarly supported. Where the height of any exposed coaming exceeds 36 in. (915 mm), the arrangement of the stiffeners and brackets or stays is to be

spec Where end c: ,minas are protected, the a•ran;,.men brackes be modif .:ef:Y.:

12.3.4 ti,In VI il,' U:c ,'.

Strength deck I:mai i ,:, greater than , ,...., supported by lori:: c-...11,.1 bull.H

,:-...r.-.:.-Nim.,- girders and they are

stiffened. SpeciC ( i. ,-.:, ratli ,-..-.il will be given to the coaming scarirg. Calculli.t that adequate buckling strength is provided may be required to be submitted.

12.4 Hatchways Closed by Sectional Sliding Covers and Secured Weathertight by Tarpaulins and Battening Devices

12.4.1 Sliding Steel Hatch Covers Covers of the sliding plate type with flanges on one edge or with stiffeners welded to one edge are to have a sufficient number of sections so that when closed, the spacing of the stianers does not exceed 42 in. (1070 mm). Plates are not to be less in thickness than required for solid steel covers in association with the spacing of the stiffeners when closed. The stiffening at the edge of the covers is not to be less effective than required for solid covers. If hatch covers of the sliding plate type are used for spans exceeding 12 ft®I in. (3.6$ ?:,..1.d0.ional support is to be provided, the details of which will be specially considered.

12.4.2 Cleats Cleats are to be set to fit the taper of the wedges. They are to be at least 2.5 in. (65 mm) wide and spaced at intervals of approximately 24 in. (610 mrn). canter to center; t 7, cleats along side or end are to be not more than 6 in. (150 mm) from. the hatch corners.

12.4.3 Wedges Wedges are to be of tough wood; they are to have a taper of not more than I in 6 and are to be not less than 0.5 in. (13 mm) thick at the toes.

12.4.4 Battening Bars Battening bars are to be provided for properly securing the tarpaulins; they are to have a width of 2.5 in. (64 mm) and a thickness of not less than 0.375 in. (9.5 mm).

12.4.5 Tarpaulins At least one tarpaulin in good condition thoroughly waterproofed and of ample strength is to be provided for each exposed hatchway. The material is to be guaranteed free from jute, and is not to be less than No. 4 cotton canvas or equal before waterproofing. Synthetic fabrics which have been demonstrated to be equivalent will be specially approved.

12.4.6 Security of Hatchway Covers At all hatchways in exposed positions on the freeboard or superstructure decks suitable provision is to be made for securing the covers after the tarpaulins are battened down.

2

Steel. 7-Vit and Clamping r:.V.6:

metric • 2.:T.F:':1) on of the rra..rrmrc stress thus calculated .tnd hirtor of

,1771..LPJ iltitnate tensile strength of the material. They are to be so designed as to limit the Ct,•f:flection to not more than 0.0028 times the span under these loads, Steel plating forming the tops of covers is to be not less in thickness than 1% of the spacing of stiffeners or 0.24 in. (6 mm) if that be greater. Where higher strength steels are used that have a higher resistance to corrosion a minimum thickness of 0.19 in. (4.8 mm) will be acceptable

the limiting ciaflection noted above is not exceeded and calculations are submitted to adi.eq•aate agalrt L:iciding. The hatch covers are to be provided with stiffening

bar:, •i•-,:-q•ured to•provide the riecessary ilgdity 1:0 p..rmit the covers handled without pc:Ina:lent deformation.

12.5.2 Other Materials The strength an,-f stiffness of covers ma-Se of materials other than steel is to be equivalent to those of steel and to veci:E..1 cons'

4.25 a not to exceed the

12.53 fear Securing Wekailertightness The means for securing and mainiair

can be mair.tainf:d in any sea conditc least 30 psi (2,1 kg

surveys. Where the hatch cover edges are sti

•:evic.€s equivalent to the over-the-centl-.1- t'

rg weathertightness are to be ic covers are to be hose-tested

he time of construction and,

ff -2ned with a horizontal gasket may be fitted at a maximum

spa.cucs of 2 in. ( 10 rand center to center. Where the hatch cover edge is stiffened by a deep bar to which the stiffener and gasket

retainer are attached the spacing of the clamps may be increased, The inertia of the cover edge is to be not less than:

/R = 0,0052S,4 in' /R = 30S cm4

Si = Spacing of cleats in ft (m) Inertia of cover edge in in.4 ( 4)

12.6 Miscellaneous Openings in Freeboard and Superstructure Decks

12.6.1 Manholes and Scuttles Manholes and flush scuttles in Position I or 2 or within superstructures other than enclosed su:yarstructures are to be closed by substantial covers capable of being made watertight. Unless secured by closely spaced bolts, the covers are to be permanently attached.

3

12.6.2 Other Openings Openings in freeboard decks other than hatchways, machinery-space openings, manholes and flush scuttles are to be protected by an enclosed superstructure, or by a deckhouse or companionway of equivalent strength and weathertightness. Any such opening in an exposed superstructure deck or in the top of a deckhouse on the freeboard deck which gives access to a space below the freeboard deck or a space within an enclosed superstructure is to be protected by an efficient deckhouse or companionway. Doorways in such deckhouses or companionways are to be fitted with weathertight doors.

12.6.3 Escape Openings The closing appliances of escape openings are to be readily operable from each side.

12.6.4 Companionway Sills In Position I the height above the deck of sills to the doorways in companionways is to be at least 18 in. (457 mm). In Position 2 they are to be at least 12 in. (305 mm).

SECTION 13 SURVEYS AFTER CONSTRUCTION (1 January 1996)

(A new Section 13 is added as shown below to indicate the applicable survey requirements.)

13.1 General

13.1.1 Application

13.1.1.1 These requirements apply to all surveys after construction for Bulk Carriers for Service on the Great Lakes

13.2 Surveys

13.2.1 Unless otherwise specified, surveys after construction are to be in accordance with the "Rules for Building and Classing Steel Vessels", Surveys after Construction, Part 1, Section 3, paragraphs 1/3.25 through 1/3.33.

4

SECTION 1

General

1.1 Classification

Vessels which have been built under the supervision of the Surveyors to this Bureau to the requirements of the "Rules for Building and Classing Steel Vessels", except where these are modified by the requirements contained in these Rules, or to their equivalent, will be classed and distinguished in the Record by the symbols +Al Great Lakes Service. Where the vessel has been specially arranged and provided with special equipment for unloading, it will be distin-guished in the Record with an appropriate notation regarding the arrangements. Where the vessel has been specially reinforced for the carriage of heavy-density cargoes, special loading arrangements, or both, it will be distinguished in the Record with a notation describ-ing the special arrangements. Fall particulars of the loading condi-tions and the maximum density of the cargoes to be provided for are to be given on the basic design plans.

1.2 Application

These requirements are intended to apply to new vessels of the Great Lakes bulk/carrier type, having machinery aft, at least one complete deck, a double bottom and side tanks, a longitudinal system of framing for the deck and bottom, and two continuous longitudinal bulkheads fitted between the freeboard deck and the bottom shell. They are intended to apply generally to vessels of welded construction, of usual form and having depths not less than L/15 at 400 ft (122 in) length and L/21 at 700 ft (213 m) length and over. Vessels whose proportions and general characteristics repre-sent departures from the foregoing and whose scantlings and ar-rangements differ from those specifically mentioned elsewhere in these Rules will be subject to special consideration.

L3 Arrangements

A transverse watertight bulkhead is to be provided at the forward end of the machinery space and a collision bulkhead is to be provided in accordance with Section 6. An afterpeak bulkhead is to be fitted to enclose the shaft tube in a watertight compartment. In addition, intermediate bulkheads or equivalent supporting arrangements are to be provided in such number and location which will, when acting in conjunction with the web frames and deep arches, provide adequate transverse strength in the hull.

SECTION 1,1 General

1.4 Breaks

Special care is to be taken throughout the structure o provide against local stress concentrations at the ends of the cargo spaces, superstructures, etc.

L5 Structural Sections

The scantling requirements of these Rules are applicable to struc-tural angles, channels, bars, and rolled or built-up sections. The required section moduli of members; such as girders, webs, etc., supporting frames and stiffeners are to be obtained on an effective width of plating basis as described below unless otherwise noted. Th.e section is to include the structural member in association with an effective wichb of plating equal to one the sun, of spacing on each side of :he z.ic..-nber, or 33% of the unsupported span 1, whichever is .11,:.ss; for girders and webs along bai ch. an effective breadth of plating equal to one-half the spacing or 16.5% of the unsupported span 1, whichever is less, is to be used. The required section modulus of each frame and stiffener is assurni..d to be provided by the stiffener and one frame space of plating to which it is attached,

1.6 Governmental Requirements

While these Rules cover the requirements for classific.,ation of new vessels, the attention of Owners, builders, and designers is directed to governmental requirements including those limiting the length and proportions of vessels.

Alternatives The Committee is at all times ready to consider alternative ar-rangements and scantlings which can be shown, through either satisfactory service experience or a systematic analysis based on sound engineering principles, to meet the overall safety and strength standards of these Rules.

1.8 Definitions

1.8.1 Length L is the length between perpendiculars, in ft or m, measured on the estimated summer load waterline from the fore side of the stem to the centerline of the rudder stock.

1.8.2 Breadth B is the greatest molded breadth in ft or m.

1.8.3 Depth D is the molded depth at side, in ft or in, measured at the niiddie L, from the inollier:. base line to the top of the strength deck beams.

SECTION 112 General

Drift d is thi2 rnoldi.=.d draft, in ft or m, from the molded base line to the

L8.5 Strength Deck The strength deck is the deck which forms the top of the effective hull girder at any part of its length. See 2.3.1.

„ SECTION 11,1 General

SECTION 2

Longitudinal Strength

2.1 General

Vessels of 400 ft (122 m) to 1200 ft (366 m) in length, intended to be classed for Great Lakes service, are to have longitudinal strength in accordance with the requirements of this section. The equations in this section are valid for vessels having depths not less than L115 at 400 ft (122 m) length and L/21 at 700 ft (213 in) length and over. Intermediate values will be determined by interpolation. Vessels whose depths are less than this, or which have an arrangement departing from those specified by the Rules, will be subject to special consideration. In general, the breadth of the vessel is not to exceed 2.6 times the depth of the vessel.

2.2 Longitudinal Hull Girder Strength

2.2.1 Strength Standard a Section Modulus The hull-girder section modulus amidships

SM expressed in inches squared-feet or centimeters squared-meters, is not to be less than obtained from the following equation.

SM = 11,1fj,

M, = total vertical bending moment, ire long tons-feet or metric tons-meters, see 2.2.2

= permissible bending stress, an long tons per inch squared or metric tons per centimeter squared, for ordinary strength steel

= 12.367+ 1. 2 1000 ! — 2,667( 1000 ) 400 L 700 ft

= 12.709 + 0.287 ( 1000 H 1.778 ( 100 0 )27°° <

L 850 ft

= 11.479 + 3.2 00)

3.5( 1000

)2 850 < L 1050 ft L L

= 15.74 — 4.5331 1000 1

1050 < L 1200 ft

= 1.948 + 0.221( 305 ) 0.42( 3/05 )2 122 L 213 m

2 = 2.001 + 0.04 305)

0.2 305 ) 213 < L 259 m

SECTION 211 Longitudinal Strength

= 1.808 ± 0.504; ) 0,551 L )2 259 < L 320 in L • )305) 305)

= 2.478 — 0.14 #320<L 366 IT/ .3051

L length, in ft or m, of vessel as defined in 1.8

The required hull-girder section modulus at locations other than amidships is to he obtained using the f j, values given above and the maximum total bending moment M, determined from the envelope curves of still-water and combined dynamic bending moments (see 2.2.16 and 2.2.2). In general, the hull-girder section modulus throughout 0.67L amidships is to be not less than that required at amidships. Special consideration will be given to the approval, away from tunidships, of still-water bending moments greater than the maximum peruiissible midship value.

b.11ininum, Section Modulus The hull-girder section modulus amidships, e:,,pressed in inches squared feet or centimeters squared-meters, for all vessels with lengths from 400 ft (122 m) to 1200 ft (366 m) is not to be less than the minimum SM determined from Table 2.2.

Where the maximum still-water bending moment is not gre:.iter than the minimum value M, given in 2.2.2a, the required section modulus amidships as specified in 2.2.1a may be determined directly from Table 2.2.

c Section Modulus Calculation In general, the following items may be included in the calculation of the section modulus, provided they are continuous or effectively developed.

Deck plating (strength deck and other effective decks) Shell and inner-bottom plating Deck and bottom girders Plating and longitudinal ii s:• of longitudinal bulkheads All longitudinals of deck, sides, bottom and inner bottom Deep longitudinal bottom girders and crown plates in self-unloading

vessels

The items included in the hull-girder section modulus amidships are generally to be extended throughout the 0.671, amidships and gradually tapered beyond. In general, the net sectional areas of longitudinal strength members are to be used in the hull-girder section modulus calculations.

The section modulus to the deck or bottom is obtained by dividing the moment of inertia by the distance from the neutral axis to the molded deck fine at side or to the base line respectively.

2.2.2 Total Bending Moment The total bending moment M,, expressed in long tons-feet or metric tons-meters, is to be obtained from the following equation.

SECTION 2 2 Longitudinal Strength

=

MS = still-water bending moment, in long tons-feet or metric tons-meters, see 2.2.2a

M„ = maximum combined dynamic bending moment, irl long tons-feet or metric tons-meters, see 2.2.2h

a Still-water Bending Moment and Shear Force For oil vessels still-water bending moments M„„, and shear force F,„, calculations far the anticipated loaded and ballasted conditions are to be submitted. The results of these calculations are to be submitted in the form of curves showing hull-girder shear forces and bending moment values along the entire ship length.

In determination of the total bending moment Mi amidships, the value of Ms,„ is not to he taken as less than the value of AL obtained from the following equation.

M s = 12.64L — 336]B 400 = L 650 [3.0L 570]B 650 < L 750 ft 13.2L — 7201B 750 < L 850 It [3.867L 1287]B 850 < L 1000 ft [74.34(L/100)2 —10.34L + 5482]B 1000 < L 1200 ft [8.8L 341]B 122 L 198 m

= [10.0L — 579]B 198 < L 229 in = [10.67L — 732]5 229 < L 259 m = [12.89L 1308]B 259 < L a 305 in

[75.54(L/30,5)2 —34.47L + 5571]B 305 < L 366 ni

= the minimum still-water bending moment: amidships, in long tons-feet or metric tons-meters

L, B as defined in 1.8.

b Combined Dynamic Bending Moment Amidships The com-bined dynamic bending moment M„ amidships, in long tuns-feet ur metric tons-meters, may be obtained from the following equation.

C Mc ,VM,„2 /1,4,2

AL, = maximum-wave-induced bending moment amidships, in long tons-feet or metric tons-meters, see 2.2.2e

M,„„ = maximum springing bending moment amidships, in long tons-feet or metric tons-meters, see 2.2.2d

C, = correlation coefficient = 0.995 — 0.172[(L/1000) — 0.4]2 inch/pound units = 0.995 — 0.172[(L/305) — 0.4]2 metric units

L = length, in ft or in, of vessel as defined in 1.8

The maximum combined dynamic bending moment at locations other than amidships may be determined in accordance with the distribution factor given in Table 21.

Consideration will be given to the combined dynamic as well as the wave-induced and springing bending moments calculated by


means of a statistical analysis based on s ip motion and vibration calculations in realistic sea states. In such cases, the calculations, computer programs used, and the computed results are to be submitted for review.

c Wave-induced Bending Moment Amidships The maximum wave-induced bending moment amidships, in long tons-feet or metric tons-meters, may be obtained from the following equations.

C„.B(L/1000)2 t-ft 114,, = C,,B(L/305)2 t-m

=9113 - 1.410L 400 L 600 ft = 8850 - 0.972L 600 < L 800 ft = 8663 - 0.738L 800 < L 1000 ft = 8518 - 0.593L 1000 < L n 1200 ft = 9261 - 4.700L 122 L 183 m = 8993 - 3.240L 183 < L 244 m = 8803 - 2.460L 244 < L 305 m = 8656 - 1.977E 305 < L 366 m

L, B = as defined in 1.8.

d Springing Bending Moment Amidships The maximum spring-ing bending moment amidships, in long tons-feet or metric tons-meters, may be obtained from the following equations.

M„ = CC,B(L/1000)3 t-ft M„ = CC„B(L/305)8 t-m C = 2296 - 0.3839L 400 600 ft

= 2224 - 0.2640L 600 < L 800 ft = 2173 - 0.2001L 800 < L 1000 ft = 2134 - 0.1606L 1000 < L 1200 ft = 2333 - 1.2798L 122 L 183 m = 2260 -- 0.8800L 183 < L 244 in = 2208 - 0.6670L 244 < L a 305 m = 2168 - 0.5353L 305< L« 366 m = 5.58 - w 1.0 a) 2.0 = 5.06N 2.0 < w

=

/ (0.142 inch/pound units

metric units

Cr ID Ati3 2Y

C, I ID

'/1/B / (0.11)2

27.33 V 2.17 1645 - 0.7549L 400 L n 600 ft

= 1483 - 0.4836L 600 < L =. 800 ft = 1374 - 0.3479L 800 < L 1000 ft = 1294 - 0.2678L 1000 < L e 1200 ft = 1645 - 2.4768L 122 = L n 183 m = 1483 - 1.5867L 183 < L 244 m = 1374 - 1.1411L 244 < L 305 in = 1294 - 0.8784L 305 < L 366 m

Y = distance, in ft or rn, from the neutral axis to the strength deck at side or to the bottom shell, whichever is greater


L = as defined in 1.8 B = as defined in L8 D = as defined in 1.8 d = as defined in 1.8 I = moment of inertia of the midship section in in2 ft2 or

cm2 — 2

The actual moment of inertia I if the vessel is to be used for calculating M. When the value oft is changed as a result of section modulus modifications, the modified I is to be used for calculating the new M,„ and new section modulus requirements. When the actual value off is not known at the early design stages, the I values determined from Table 2.2 may be taken as initial value.

2.2.3 Permissible Shear Stress In general, the thicknesses of the side shell and longitudinal bulk-head, where fitted, are to be such that the total shear stresses as obtained from 22.3a are not greater than 6.75 long tons per inch squared (1.065 metric tons per centimeter squared) provided the critical shear buckling stress of the plating is satisfactory.

a Calculation of Shear Stresses In calculating the total shear stresses due to still-water and dynamic loads in the side shell and longitudinal bulkhead plating, the maximum numerical sum of the shearing force in still water F4 and that induced by wave and springing F,1 at the station examined, is to he used. For vessels without con tinuoiis longitudinal bulkheads, the total shear stress f, in the side shell plating clear of the wing tanks may he obtained from the following equation.

f, (F + Fd )m/(24t0t/in, 2 f, = „ + Fd )rn/(200ti ) tkm2

f, = total shear stress in long tons per inch squared or metric tons per cun:i,..incter squared

= moment of inertia, in in. 2 ft2 or C1112 — m2, of the hull- girder section at the section tinder consideration

m = first moment, in in.2 — ft or crn2 — rn, about the neutral axis, of the area of the effective longitudinal material, taken at the section under consideration

t

= thickness, in in. or cm, of the side shell plating at the position under consideration

= as specified by 2.2.3b. as specified by 2.2.3h.

The total shear stress in the side shell in way of wing tanks, and for vessels having continuous longitudinal bulkheads, the total shear stress in the side shell and longitudinal bulkhead plating is to be calculated by an acceptable method. One simplified method is shown in Appendix A. Consideration will be given to alternative methods for shear stress calculations.

b Hull-girder Shearing Force The hull-girder shearing forces in still water F, are to be submitted as required by 2.2.2a. The envelope curve of maximum shearing forces induced by wave and


springing Fd s siar,..ez in Figure 2.1 may be (.1)tain, the following equation.

F KMA

F,- = maximum shearing corce, in long tons or metric tons: induced by wave am] springing maximum combined dynamic hull-girder bending moment amidships, in long tons-feet or metric tons-meters, as specified by 2.2.2b

L = length, in ft or m, of vessel as defined in 1.8 K

3.4 between 0.851, and 0.701, 2.3 between 0.60L and 0.45L 3.2 between 0.351_, and 0.201, 0.0 at FT and AP

The length range is measured from the AP and at mu:medial:2 locations the K value may be obtained by interpolatii)11.

.3 Strength Deck and Other Effective Decks

2.3.1 Strength Deck The uppermost deck to which the side shell plating extends for any part of the ength of the vessel is to be considered. the strength deck for 7- hat port.i'mA the leng:h. The thickneis 4the ,,tring(r plates r:-id deck plating are to comply with the requi..,..-tments In g,c.=riei the etTeclive sectional area of the dcel:: for c;.:kicu:iat.: the section modulus is to exclude hatchways and other onenings in the deck and is to Oe maintained throughout 0.67L amidships.

2.3.2 Effective Lower Decks To be eci:,sidered effective for use sectio2.1: 7itod us, the thickness JO:, the re: ii.-. o18,3. The sectional ar(-: of e used in calculating the section niedultis are to be tamed throw.7,hout 0.67L

.4 Loading or Loading Instrument

A loading manual or loading instrument based on still-water bending conditions is to he provided on all vessels and submitted for review. This manual or instrument is to show the effect of the various loaded and ballasted conditions upon the longitudinal 1).?Ifoling, manual or loading instrument is to indicate the still-water bending moments at amidships and at other locations along the length of ihe vessel as necessary.

.5 Higher-Strength Materials

2.5.1 General Vessels in which the effective longitudinal material of the upper, lower, or both flanges of the mai h., h grder are constructed of

ECTION 2 6 Longitudinal Strength

materiai; rilElzha, propertit, s fii t lL nary-strnrigin st:3:o;. . tura! steel nrr. ik,ive ngth generah, aecerdi,ne, with t1ri pi-rt.,-ediig paragraphs this section, e:,.:cepl as modified by 2.5. Apr:lir:at:ions of higher-strength material are to he -c2cmtinuous throughout the midship 0. 67L of the vessel, and are to he extended to suitable locations below the strength deck and above the bottom, so that the stress levels will be satisfactory also for the mild steel structure. Longitudinal framing members are to he essentially of the same material as the plating they support. Calculations showing that adequate strength has been provided against buckling are to be submitted for review. Care is to be taken. against the adoption of reduced thicknesses of members which may be subject to damage during normal operation.

2.5.2 Rull-girder Section ." When either the top or ho of the hull girder, or both, is construe:fed of higher-strength material, the section modulus Sikihr, may be obtained from 2.2. la by substituting the permissible stress f„ with fp/Q

= J/Q)

Q = 70900/(1 2L:73) inch/pound units 49.9241 2f..73 metric units specified ,.:!1(1 point for the higher-strength material or its specified n,i3iiinu yield strength at 0,2% offset, or 72% of the sierilicri mini:mi.:I-a tensile strength, in psi or kWinin2,

is he lesser U = s.pecified minimum tensile strength of the higher-strength

maL-trial, in psi or kg/mm2 Mt = total bending moment, in long tons-feet or metric tons-meters,

see 2.2.2

determining the maximum total bending :nonient M1 , the actual moment of incml a of the higher-strength i.dsi ii section is to be

hi calculate 11„ as specified in 2.2.2d. Thz., value of f,,/Q is not to be taken greater than the critical

buckling stress of the deck and bottom plating. Special consideration will be given to the application of Q less than 0.72.

In addition, the hull-girder section modulus amidships of a vessel constructed of higher-strength materials is also not to be less than the miaimum SM given in Table 2.2 for Q = 0.78 or 0.72. For

Q values, the minimum SM may he obtained by interpolation.

2,5.3 Permissible Shear Stress Where the side shell or longitudinal bulkhead is constructed of higher-strength material, the permissible shear stresses indicated in 2.2.3 may be increased by the factor 1/Q, provided the critical buckling stress of the plating is satisfactory.


2,5,4 Hull-girder Moment of inertia As specified in 2.2.2d, the actual moment of inertia of the midship section for a vessel constructed of higher-strength cmAerial is to be used to calculate the springing bending monieni .11,.„. A set of initial values of I is shown in Table 2.2, for ordinary-strength steel (Q = 1.0) and for higher-strength materials with Q = 0.78 and 0.72 respectively. For higher-strength materials with Q values between 0.72 and 1.00, the initial I values may be obtained by interpolation.

The inertia of a vessel constructed of higher-strength material in the top, bottom or both flanges of the hull girder is to be not less than obtained from the following equation.

Inrs = 0.45(SM)D,

I jts = hull girder moment of inertia, in in.2-ft2 or cm2-m2, of higher-strength material

SM = minimum hull-girder section modulus of an ordinary strength steel vessel of the same dimensions as determined from 2.2.1b

D = basic depth from 11.1, column 2

FIGURE 2.1

Envelope of Wave-Induced Shearing Forces

AP

FP

ECT1ON 2 8 Longitudinal Strength

TABLE 2.1

Combined Dynamic Bending Moment Distribution Factor

Intermediate values of distribution factor may be determined by interpola-tion.

Distribution

Position Factor

Station 0 AP

2 0.17

4 0.57

6 0.76

8 0.95

9 1.00

10 1.00

11 1.00

.12 0.96

14 0.76

16 0.44

18 0.12

20 FP 0


TABLE 2.2

talues of Z, in in.2, for Q m 1.0 (Ordinary Strength Steel)

:B = :B13/2 = nil ■ ;:l Values of I

D, and fi are as defined in 1.8, in ft., (3 is as defined in 2.5.2.

Dlvijd

• {,ft) 0.70 0.75 0.80 0.85 0.90 0.95 1.00 7.05 .1.10 1.15 1.20

400 168 168 168 168 168 .168 168 420 184 184 184 184 183 183 183 440 200 200 200 200 200 200 200 460 217 217 217 217 217 217 216 480 235 235 235 234 234 234 234

300 254 253 253 953 253 253 252 520 273 273 272 272 272 272 272 271 540 293 293 292 '292 292 292 291 291 560 314 314 313 313 313 312 312 312 580 336 336 335 335 334 334 334 333

600 359 358 358 357 357 .357 356 356 620 383 382 382 381 381 380 380 379 640 408 407 407 406 405 405 404 404 660 435 1 1 ¢ 433 432 431 431 430 433 680 462 161 459 458 438 457 456 456

700 491 00 489 488 487 486 485 484 484 720 521 520 518 517 516 515 514 513 513 740 552 551 549 548 547 546 .515 544 543 760 585 583 582 580 579 577 576 575 574 780 619 617 615 614 612 611 609 608 607

800 653 651 649 647 645 644 64.2 641 820 689 687 685 683 681 680 673 677 840 728 725 723 721 71.9 717 715 714 712 860 768 765 763 760 738 7.56 754 752 751 980 810 807 804 802 799 797 795 793 791

500 855 851 848 845 842 840 837 835 833 920 901 897 893 890 887 885 882 879 877 340 945 941 937 934 931 928 926 923 960 995 991 987 983 980 977 974 971 580 1017 1042 1038 1034 1031 1027 1024 1021

300 102. 1.097 1092 1088 1.084 .1080 1077 1073 1070 320 1153 1148 1144 11.40 1135 1.132 1128 1125 340 1219 1213 1207 1202 1198 1193 1189 1185 1182 360 1281 1275 1269 1264 1259 1254 1250 1245 1241 )80 1340 1334 1328 1323 1318 .1313 1308 1304

100 1408 1402 1395 1390 1384 1379 1374 1369 120 1479 1472 1465 1459 1453 1447 1442 1437 140 1553 1545 1538 1531 1525 1519 1513 1508 160 1.630 1622 1614 1607 1600 1594 1588 1582 180 1712 1703 1695 1687 1680 1673 1667 1660 100 1799 1789 1781 1772 1765 1757 1750 1744

FCTION 2 10 Longitudinal Strength

TABLE 2

Values of Z, in in.2, for 0 = 0.78

ZB = Mininotin SM ZBD/2 = initial Values of 1

73, D, and d are defined in 1.8, in ft., Q is as defined in 2.5.2.

L (ft) 0.70 0.75 0.80 0.85 0.50 0.95 1.00 1.05 1.10 1_15 1.20

400 131 131 131 131 131 131 131 420 144 143 143 143 143 143 143 440 156 156 156 1.56 156 156 156 460 170 170 170 169 169 169 169 480 184 184 183 183 183 183 183

500 198 198 198 .198 198 198 197 520 214 213 213 213 213 213 212 212 540 229 229 229 229 228 228 228 228 560 246 246 245 245 245 245 244 224 580 263 263 263 262 262 262 261 261

600 282 281 281 280 280 280 279 279 620 301 300 300 209 299 298 298 298 640 321 320 319 319 318 318 317 317 660 342 341 340 339 339 338 338 337 680 36.3 363 362 361 360 360 359 358 358

700 386 385 384 384 383 382 381 381 380 720 410 409 408 407 406 405 405 404 403 740 435 434 433 432 431. 430 429 428 427 760 461 460 459 457 456 455 454 453 452 780 489 487 486 484 483 482 480 479 478

800 515 514 512 511 509 508 507 506 820 545 543 541 539 538 537 535 534 840 576 573 571 570 568 566 565 563 562 860 608 606 603 601 599 598 506 594 593 880 642 639 637 635 632 631 629 627 625

900 677 674 672 669 667 665 663 661. 659 920 714 711 708 706 703 701 698 696 694 940 750 746 743 741. 738 736 733 731 960 790 786 783 780 777 775 772 770 980 832 828 824 821 818 815 812 810

1000 875 871 868 864 861 858 855 852 849 1020 921 917 913 909 905 902 899 896 893 1040 969 965 960 956 952 949 945 942 939 1060 1020 1015 1010 1006 1003. 997 994 990 987 1080 1067 1062 1057 1053 1049 1045 1011 1037

1100 1122 .1116 1111 1106 1102 1098 1094 10,30 1120 1179 1173 1167 1162 1157 1153 1118 1144 1140 1238 1232 1226 1220 121.5 1210 1205 1201 1.160 1300 1293 1287 1281 1276 1270 1265 1261 1180 1366 1359 1.352 1346 1340 1334 1329 1324 1200 1436 1428 1421 1414 1408 1402 1396 1391


TABLE 2.2

Values of Z, in in.2, for Q = 0.72

-613 — Minimum SM 4BDI2 = Initial Values of I

D, and d are as defined in 1.8, in ft., Q is as defined in 2.5.2.

DIVF3d

(ft) 0.70 0.75 0.80 0.85 0.90 0.95 1.0X1 1.05 1.10 1.15 1.21

400 121 121 121 121 121 121 121 420 133 132 132 132 132 132 132 440 144 144 144 144 144 144 144 460 157 157 157 156 156 156 156 480 170 170 169 169 169 169 169

500 183 183 183 183 183 182 182 520 197 197 197 197 197 196 196 196 540 212 212 212 211 211 211 211 211 560 228 227 227 227 226 226 226 226 580 244 243 243 243 242 242 242 241

600 261 260 260 259 259 259 258 258 620 278 278 277 277 276 276 275 275 640 297 296 295 295 294 294 294 293 660 316 315 315 314 313 313 312 312 680 336 336 335 334 333 333 332 332 331

700 358 357 356 355 354 354 353 352 352 720 380 379 378 377 376 375 375 374 373 740 403 402 401 400 399 398 397 396 395 760 428 426 425 424 423 421 421 420 419 780 453 451 450 449 447 446 445 444 443

800 478 476 475 473 472 471 470 468 820 505 503 502 500 499 497 496 495 840 534 532 530 528 527 525 524 522 521 860 564 562 560 558 556 554 553 551 550 880 595 593 591 589 587 585 583 581 580

900 628 626 62.3 621 619 617 615 613 611 920 663 660 657 655 652 650 648 646 644 940 696 693 690 687 685 683 681 679 960 733 730 727 724 721 719 717 714 980 772 769 765 762 759 757 754 752

1000 813 809 806 802 799 796 794 791 788 1020 856 852 848 844 841 838 835 832 829 1040 901 896 892 888 885 881 878 875 872 1060 948 943 938 934 930 927 923 920 917 1080 992 987 982 978 974 971 967 964

1100 1043 1038 1033 1028 1024 1020 1016 1013 1120 1096 1090 1085 1080 1076 1071 1067 1063 1140 1151 1145 1139 1134 1129 1125 1120 1116 1160 1209 1203 1197 1191 1186 1181 1176 1172 1180 1270 1263 1257 1251 1246 1240 1235 1231 1200 1335 1328 1321 1315 1309 1303 1298 1293

SEMON 211 2 Longitudinal Strength

TABLE 2.2 Values of Z, in cm2, for 0 = 1.0 (Ordinary Strength Steel)

ZB = Minimum SA1 1151)12 = Initial Values ofl B, U , and d are as defined in 1.8, in m., Q is as defined in 2.5.2.

I,* 0.70 0.75 0.80 0.85 0.90 0.95 1.00 105 1.10 1j5 1,20

120 1057 1056 1056 1055 1055 1055 1055 125 1138 1137 1137 1136 1136 1136 1135 130 1222 1222 1221 1220 1220 1220 1219 135 1310 1309 1308 1307 1307 1306 1306 140 1400 1399 1398 1398 1397 1396 1396

145 1.494 1493 1492 1491 1490 1489 1488 150 1591 1590 1588 1587 1586 158.5 1584 155 1691 1690 1688 1.687 1686 1684 1683 1682 .160 1795 1793 1791 1790 1788 1787 1786 1785 165 1902 1900 1898 1896 1895 1893 1892 1890

170 2013 2011 2008 2006 2004 2003 2001 1999 175 2129 2126 21.23 2121 2118 2116 2114 2112 180 2248 2245 2242 2239 2236 2.234 2232 2229 1.85 2372 2368 2365 2.361 2358 2356 2353 2351 190 2501 2496 2492 2489 2485 2482 2479 2476

195 2634 2629 2625 2620 2617 2613 2610 2607 200 2773 2767 2762 2757 2753 2749 2745 2741 205 2917 2910 2905 2899 2894 2890 2885 2881. 2878 210 3066 3059 3052 3046 3041 3036 3031 3026 3022 215 3221 3213 3205 3.199 3193 3187 3181. 3177 3172

220 3381 3372 3364 3356 3.350 3343 3337 3332 3326 225 3547 3537 3528 3520 3512 3505 3498 3492 3486 230 3719 3708 3698 3688 3680 3672 3665 3658 3651 235 3897 3885 3874 3863 3854 3645 3837 3830 3822 240 4068 4056 4044 4034 4024 4015 4007 3999

245 4257 4244 4231 4220 4209 4200 4190 4182 255 4655 4639 4624 4611 4598 4586 4575 4565 4553 265 5085 5066 5049 5032 5017 5003 4990 4978 4967 275 5549 5526 5506 5487 5469 5453 5437 5423 5409 285 6020 5996 5974 5954 5934 5916 5899 5883

295 6551 6523 6497 6473 6451 6430 6411 6392 305 7121 7089 7060 7032 7007 6983 6960 6939 6919 315 7736 7700 7666 7635 7605 7578 7552 7528 7505 325 8400 8359 8321 8285 8252 8220 8191 8163 8137 335 9069 9026 8966 8948 8912 8879 8847 8818

345 9824 9776 9731 9688 9648 9611 9575 9541 3.55 10641 10587 10536 10489 10444 10402 10362 10325 365 11536 11476 11420 11367 11317 11270 11225 11183


TABLE 2.2

Values of Z, in erne, for 0 = 0.78

Minimum SM. ?13I312 Initial Values of I 3, /3, and d are defined in 1.8, in in., as defined in 2.5.2.

DI 03(1

(m) 0,70 0.75 0.80 0.85 0.90 0.95 1.00 1.0,5 1.10 1.1.5 1.20

120 825 825 825 824 824 824 823

125 839 889 888 888 887 887 887 130 955 955 954 954 953 953 952 135 1024 1023 1022 1022 1021 1021 1020 140 1095 1094 1093 1093 1092 1091 1091

145 1169 1168 1167 .1166 1165 1.104 .1164 150 1245 1244 1243 1242 1241 1.240 1239 155 1324 1322 1321. 1320 1319 1318 1317 1316 160 1406 1404 1402 1401 1400 1399 1398 1397 165 1490 1488 1487 1485 1484 1482 1481 1481)

1.70 1578 1576 1574 1572 1570 1569 1567 1.566 175 1669 1.667 1664 1662 1660 1658 1657 1655

180 1764 1761 1758 1756 1753 1751 1749 .1747 185 18362 1859 1855 1853 1.850 1848 1845 1843 190 1964 1960 1957 1953 1950 1948 1945 1943

.195 2070 2065 2061 2058 2054 2051 2048 2046 200 2180 2175 2170 2166 2163 2159 2156 2153 205 2294 2289 2284 2279 2275 2271 2267 2264 2261 210 2413 2407 2401 2396 2391. 2387 2383 2379 2375 215 2536 2529 2.523 251.7 2512 2507 2502 2498 2494

220 2664 2656 2649 2643 2637 2631 2626 2621 2617 225 2796 2788 2780 2773 2766 2760 2754 2749 2744 230 2934 2924 2915 2908 2900 2893 2887 2881 2876 235 3076 3065 3056 3047 3039 3032 3025 3015 3012

240 3212 3201 3192 3183 3175 3167 3160 3153

245 3363 3352 3341 3332 3323 3314 3306 3299

255 3682 3668 3656 3644 3633 3623 3614 3605 3597 265 4026 4010 3996 3982 3969 3957 3946 3936 3926 275 4398 4379 4362 4346 433.1 4317 4304 4292 4281 285 4776 4756 4737 4720 4704 4689 4674 4661

295 5202 5179 5157 5137 5119 5101 5085 5069 305 5660 5634 5609 5586 5565 5545 5526 5508 5491

315 6154 6124 6097 6071 6046 6023 6002 5981 5962

325 6688 6654 6622 6593 6565 6539 6515 6492 6470 335 7225 7189 7156 7125 7096 7068 7042 7017

345 7832 7792 7755 7720 7688 7657 7627 7599

355 8488 8444 8403 8364 8328 8293 8260 8229 9158 365 9206 9112 9069 9029 8990 8954 8919


TABLE 2.2

Values of Z, in cm2, for = 0.72

ZIP Minim:1m SA1 Z8D/2 imitifd Values of I

D, and d ;!re as defined in 1.8. in m., Qis as dt.ILoki in 2.5.2.

L ant 0.70 0.75 0.:3 0.85 0,90 0M5 1.00 1.05 1.10 Li5 1.20

120 762 762 762 761 761 761 760 125 821 821 820 820 820 819 819 130 882 882 881 881 880 880 880 135 946 945 944 944 943 543 943 140 1012 1011 1010 1009 10GP 998 1008

145 1080 1079 1078 1077 1 6 1076 1075 150 1150 1149 1148 1147 1146 1146 1145 155 1224 1222 1221 j220 1219 1218 1217 1216 160 1299 1298 1296 1295 1.294 1293 1292 1291 165 1378 1376 1374 1373 1371 1370 1369 1368

170 1459 1457 1455 1453 1452 1450 1449 1447 175 .1544 1541 1539 1537 1335 1533 1532 1530 180 1631 1628 1626 1624 1621 1619 1618 1616 1.85 1722 1719 1716 1714 17.11 1709 1707 1705 190 1817 1813 1810 1807 1804 1802 1799 1797

195 1915 1911 1907 1904 1901 1898 1895 1.892 200 2018 2013 2009 2005 2001 1998 1995 1992 205 2124 2119 2114 2109 2105 2102 2098 2095 2092 210 2234 2228 2223 2218 2213 2209 2205 2202 2198 215 2349 2342 2336 2331 2326 2321 2317 2312 2309

220 2468 2460 2454 2447 2442 2437 2432 2427 2423 225 2591 2583 2575 2568 2562 2556 2551. 2546 2541 230 27.18 2709 2701 2694 2637 2680 2674 2669 2663 235 2851 2841 2832 2823 2816 2809 2802 2796 2790 240 2977 2967 2958 2949 9949 2934 2928 2921

245 3118 3101 3097 3088 3079 3071 3064 3057 255 3415 3402 3390 3379 3369 3359 3350 3342 3334 265 3735 3720 3706 3693 3681 3670 3660 3650 3640 275 4082 4064 4048 4033 4019 4005 3993 3981 3970 285 4433 4414 4397 4381 4365 4351 4337 4325

295 4830 4808 '4788 4769 4752 4735 4720 4705 305 5257 5233 5210 5188 5168 5149 5131 51.14 5098 315 5718 5690 5664 5639 5616 5595 5574 5555 5537 325 6215 6183 6154 6126 6100 6076 6053 6031 6010 335 6715 6682 6651 6622 6594 6568 6544 6521

345 7281 7244 7209 7177 7146 7117 7089 7063 355 7892 7851 7813 7777 7743 7710 7679 7650 365 8561 8516 8474 8434 8396 6360 8326 8293

SECTION 2 15 Langit adine! Strength

SECTION 3

Bottom Structure

3.1 General

A double bottom is to be fitted between peak bulkheads where practicable. In general, it is to be arranged with a center keelson and a system of side keelsons and plate floors in accordance with the following paragraphs.

3.2 Center Keelson

The depth and thickness of the center keelson is not to be less than given in Table 11.1, column 8, nor is the depth to be less than 0.75 in. per ft (6.3 mm per 100 mm) of beam B, where B may he measured between longitudinal side tank bulkheads. Where plate floors are spaced more than 3 ft (0.915 m), intermediate stiffening of the keelson may be required. Where floors are spaced more than 7.5 ft (2.3 m), intermediate docking brackets of the same thickness as the floors are to be provided. Docking brackets are to extend and be attached to the first longitudinals outboard. For depth of double bottom requirements for self-unloading vessels see 3.7.2.

3.3 Side Keelsons

Full depth side keelsons, spaced not more than 10 ft (3 m), are to be not less in thickness than given in Table 11.1, column 9. Where plate floors are spaced more than 3 ft (0.915 rn), intermediate stiffening may be required.

3.4 Floors

Full depth floors of the thickness given in Table 11.1, column 9, are to be fitted at maximum intervals of 6 ft (1.8 in) in way of the cargo spaces and stiffeners are to be fitted in line with each bottom longitudinal. Within the machinery space the floors are to be spaced at every frame under the engine, boiler, and major auxiliary foun-dations. Within the peaks, the spacing of floors is not to be greater than 24 in. (610 mm) and the depth, thickness, and stiffening arrangements are to be specially considered. Tank end floors are to meet the requirements for tank bulkheads in the same location.

3.4.1 Bilge Brackets Where floors are spaced more than 4 ft (1.2 m), intermediate bilge brackets are to be fitted. Alternatively, the shell at the bilge may be

SECTION 311 Bottom Structure

rdi ,i.1.2:2( '-:; a.. 11'17::::'.%- kW-ft: IfttAL: ' LiCaltii“4. Fit {:` 1 ,...d.i:n:.,_ b .-., ..z...d ...:.Al.. si, longitu, i 4,1;:ds.

3.5 Lightening and Access Holes

In general, the center keelson in way of the double bottom is to be intact, except this requirement may be modified near the ends of the vessel or where other intact longitudinal divisions are provided. Lightening and access holes in floors and side keelsons are generally to be located at mid-depth of the member and are not to have a vertical dimension greater than one-half of the depth of the member. Whei-e ning or access holes are in close proximity to drainage cut-c ts 1,1 franA,s, chocks or other compeiasation may

'.ceoss hoic.!-; not to be eut th'..! 11.)ij (.! ''fri I a . ::1. rd plane of the side

mIkhead or oEbey. locations subject high shear 1.3!" buckling loads.

3,6 Inner-bottom Plating

hysl; to be adopted througb the space mid the hi:A.:Less is to be 0.50 in. (1.2.5 nun where stiffene:s ace mm) or less. and 0.75 in. (19 nnn) with 36 in

5 rani) stiffener spacing. Other methods of construe- tion, sue.. 7:h sscx iat d 'N.:ill the use of channels, will be specially considered.

3.7 Bottom Structure in Self-unloading Vessels

3.7.1 marier-bottom Plating ihu boi..:or: de:::ertnined m accordance with Section 1.:!leads. trausver,e 17iiines are fittA, the plating thicknesses will be

spec conside--en into account the buckling characteristics of the inner bottom piRl

3.7.2 Floors In vi.!ssPis v, here the bottom is supported by a deep centerline girder or a syste girders, the depth of the double bottom is not to be less . (760 mm) or 1.5 in. per ft (12.6 mm per 100 mm) of span, iever is greater, wtiere the span may be measured between deep girders or between a deep girder and side tank Imlkheads. Full-depth floors may be fitted at intervals of not more than 8 ft (2.44 m) and stiffeners are to be fitted in line with each longitudinal. The thickness of the floors may be required to be increased over the il!ic;:,,ness required by Table 11.1, column 9, Or intermediate Boors added where subject to high shear leads.

SECTION 3 2 Bottom Structure

3.7.3 Longa,: A:;,11 Each iongitrutirial ,, 1.5 in. per ft (I2 100 . he.(StiOn MOdUIUS S.1/1 is to he not less Ibiained from equation.

SM 0.0025ebh12 irz.d3 % — 4.74c/44 2 cm"

c = 1.5 b = sum of half-lengths, in ft or sn, (on each side o.f girder) of floors

supported h = one-half the distance, in ft or in, from the base line to the load

line

in ft or in, between transverse buli<hcacls i r r supports

0,71.1eic eifecii-,,..e brackets a: may be nm as itii -11.-Eille 11.2.

3.8 Higher-strength Materials

3.8.1 General In gel:v.:T.:A. ,posed a, ;F.:cations hi.gber-stren materials Jr bottom structures are h the requirements ti i tins section, but may -mociifi.:-d as T..f2,rmitted by 3.8.2 il- icz

exere::sed to avoid the adoption of reduced thicknossc:5 such as „ -7;1.-! to damage during lEarlUi.!

calculations showing adequate bnekiiii2 stre- myvidE-d may be required to s, ..bcoitted. Longit framin• are to be of essen - material as the piatiug supuitir%

3.8.2 Pla Inrier-boto.=,;:u , constrvicted of higher-stre k kq F.1;11 a R3 • is to be not less in thick:J.:26.s requiri,.d pree, g pay-ag,,-;3ph. of this section as inotlifie.: the billowing equation.

thw = It — + 2\1031 + c k 6cness of higher-streugtii inaierial, in in. or mm

t = thickness of mild steel, as required by preceding paragraphs of this section, in in. or if:n1

c = 0.06 in. (1.5 mm) Q = as defined in 2.52

3.8.3 Center Girders, Side Girders, and Floors Center girders, side girders, and floors, where constrinAnd of higher strength materials, are gener inDly witli the rennirements of - the 3.2, 3.3, 3.4, or 2.7.2 k- may b(.• modified as peri - nitted by the following equation.

SECTION 3,3 Bottom Structure

tms = tt e)[(Q + Z\1(7)/31 + c

i,„ t, c = as defined in 3.8.2 as defined in 2.5.2

L8.4 Bottom Girders in Self-unloading Vessels I'he section modulus required by 3.7.3 may be modified provided :he plating to which the higher strength steel girder is attached has :he same strength properties. The section modulus of the higher arength steel girder is not to be less than obtained from the follow-rig equation.

SMh = (SM)Q

3Mh„ = section modulus of higher strength steel members, in in.3 or Erns

= section modulus of ordinary strength steel members as required by 3.7.3, in in.3 or cm3

2 = as defined in 2.5.2

SECTION 314 Bottom Structure

SECTION 4

Shell Plating

4.1 Amidships

The thickness of the shell plating within the midship 0.67L is not to be less than is required for purposes of longitudinal hull girder strength in accordance with 2.1 nor is it to be less than is required by Table 11.1, column 4, with associated footnotes. The thickness of the bilge plating is to be in all cases 0.06 in. (1.5 mm) greater than the thickness required for the bottom shell plating.

4.2 Sheerstrake

The thickness of the sheerstrake within the midship 0.67L., is to approximate that of the stringer plate on the freeboard deck. The top edge of the sheerstrake is to be smooth and, in general, fittings are not to be welded to the top edge of the sheerstrake within the midship 0.75L.

4.3 End Plating

The thickness of shell plating at ends, and immersed bow and stern plating is to be in accordance with Table 11.1, columns 6 and 5, respectively. End thicknesses are not to extend for more than 0.11, at ends and are to be gradually tapered to the midship thickness. Plate thickness and connections to the stern frame and boss are to be specially considered. In the vicinity of the hawse pipes and below the anchor pockets, the plating is to be increased in thickness over a width sufficient to provide added protection in way of the anchor flukes.

4.4 Compensation

All shell openings are to have well-rounded corners and are to he kept well clear of breaks in superstructures or other highly stressed areas and local compensation may be required to maintain the longitudinal and transverse strength of the hull.

4.5 Special Material

Vessels with a length of 450 ft (137 m) and above are to be provided with sheerstrakes of special material in accordance with the "Rules for Building and Classing Steel Vessels". Where a radiused gunwale plate is fitted, the above requirements for special material may he

SECTION 411 Shell Plating

Strakes 1.1.e , .e :also to be pro-irk:4-i at the lower tur:.;. of the ./essels of 4:50 ft 137 m) in lend ra above. These strakes niaterii.ii are to be 4.1c.:ted throughout the midship 0.67L. Riveted seams as an alternative the material requirements of this paragraph will be specially considered: See also 8.3.4.

4.6 Higher-strength Steel

In general, applications of iigher-strength materials for shell plating are to take into consideration the suitable extension of the higher-strength material above and below the bottom and deck respectively, as required by 2.5.1. Care is to be exercised against trhe adoptiot; of red end thic7,,esses of material that might he subject daLnage ishr:ing normal opel Calculations showing ti:i.at adequate, lnick- ling strength is p yin hled Tildy be required to be submitted. The tfli cknesses of Lee bottom and. side shell are not to be Less than re.riuirecl for h)ngitudinal strength by Section 2. The requir...a..konts

preeci. 2a;.;lgraphs of Section 4 may be modified but are not to be less obtailied from 4.6.1 through: 4.6.2.

4.6.1 Bottom PI- Where constructed of higher strength -steel, the bip •, :!:1g is to be not less in thickness than obtained from the IF:,

this = It — +

tr,„ thickness of higher-strength steel, in in. or mm t = thickness, in in. or mm, of ordinary-strength steel as required

by the preceding paragraphs of this section c = 0.06 in. (1.5 mm) Q = as defined in 2.5.2

4.6.2 Side Shell Plating Where constructed of higher-strength steel, the side szie.. :kg is to be not less in thickness than obtained from the following 011

the, + 2VQ/31 + c th„, t, c = as defined in 4.6.1. Q as defined in 2.5.2

4.6,3 End Plating , constructed of higher-strength tho thielf:ness of eile_

plating, immersed bow, and ',torn plating be subject to special consideration.

SECTION 4 2 Shell Plating

SECTION 5

Framing

5.1 General

The sizes and arrangement of frames are to be as required by this section. The equations apply to vessels having bulkhead and web frame arrangements as outlined by 1.3.

5.2 Scantlings

The frames may be flat bars, inverted angles, flanged plates, or other rolled structural sections, Holes cut in webs or outstanding flanges may require compensation.

5.3 Frame Spacing

Table 11.1 is based on a 36 in. (915 mm) spacing of frames throughout the midship portion of the vessel, longitudinal framing of the bottom shell, and either transverse or longitudinal framing of the side shell. The spacing in peaks and the distance from the stem to the first frame is not to exceed 24 in. (610 mm).

5.4 Bottom and Side Shell Framing

Each structural section for bottom longitudinals and shell frames in the side tanks is to have a section modulus SM not less than obtained from the following equation.

SM = 0.004Ichs/2 in.3 SM = 7.9chs12

c = 1.30 for bottom lougitudinals = 1.00 for longitudinal or vertical side shell frames

h = distance, in ft or m, from the longitudinal, or from the middle of 1 for vertical members, to the load line, or to a point located at two-thirds of the distance from the top of the tank to the top of the overflow, whichever is greater; h is not to be taken at less than 6 ft (1.83 m)

s = spacing of frames, in ft or m span, in ft or m, between floors, between decks or supporting stringers, between transverse bulkheads or webs, or between the toes of brackets where fitted in accordance with Table 11.2. The value of 1 is not to be taken as less than 6 ft (1.83 rn).

It is recommended that the longitudinal system of framing of the bottom be carried at least to the lower turn of the bilge. Lorigitudi-

SECTION 511 Framing

nals around the bilge, if fitted, are to be graded in size from that required for the lowest side longitudinal to that required for bottom longitudinals. Where the hull-girder section modulus to the bottom is in excess of the required hull-girder section modulus, the c value of 1.30 for bottom longitudinals may be modified.

5.5 Inner-bottom Longitudinals

Where cargo is carried on the inner bottom, the section modulus SM for inner-bottom longitudinals is not to be less than 85% of that required for bottom longitudinals as described in 5.4 nor is the section modulus for inner-bottom longitudinals throughout the cargo space of bulk carriers where subject to mechanical damage to be less than obtained from the following equation.

SM = 0,004101s/2 in.3 SM 7.9chsi2 cm3

e = 1.75 h = distance, in ft or m, from the inner bottom to the deck at center s = spacing of longitudinals, in ft or m

span, in ft or m, between floors

Where the density of the cargo to he carried is greater than 150 1[03- (2400 kg/m3), the section modulus is to be increased in the ratio of the actual density to 150 lb/ft3 (2400 kg/m3). Where cargo is not carried on the inner bottom, the required section modulus is to be obtained from the above equation using a value of c equal to 1.00, and a value of h equal to the distance, in ft or in, from the inner bottom to the load line, or to a point located at two-thirds of the distance from the top of the tank to the top of the overflow, which-ever is greater, however it is not to be taken as less than 6 ft (1.83 m).

5.6 Stringers and Webs

5.6.1 Strength Requirements Each stringer and web which supports frames in the side tanks is to have a section modulus SM not less than obtained from the following equation.

SM = 0.0025chs12 in a SM = 4.74chs/2

c = 1.5 h

distance, in ft or m, from the center of the area supported to the load line, or to a point located at two-thirds of the distance from the top of the tank to the top of the overflow, whichever is greater

s = sum of the half-lengths, in ft or m, on each side of the stringer or web of the frames supported.

/ = span, in ft or m, between transverse bulkheads or webs, or between decks or other supports

Where effective brackets are fitted, 1 may be modified as described in Table 11.2.

SECTION 5 2 Framing

Transverse webs are to be arranged in line with solid floors. Where efficient struts are fitted between the side shell web and a web on the side tank bulkhead, the combined section moduli of the webs may be used.

In self-unloading vessels where web frames serve as the only supporting structure for the arch beams, the web-frame section modulus is to he not less than 75% of that required for the arch beam.

5.6.2 Proportions Stringers and webs are to have depths not less than 1.5 in. per ft (12.6 mm per 100 mm) of span / when no struts are fitted and 1 in. per ft (8,4 mm per 100 mm) when struts are fitted. The depth is not to be less than 2.5 times the depth of the slots and the thickness is not to be less than 0.01 in, per in. (1 mm per 100 mm) of depth plus 0.12 in. (3 mm), but need not exceed 0.44 in. (11 mm).

5,6.3 Stiffeners and Tripping Brackets Stiffeners are to extend for the full depth of the stringer or web on alternate frames, and where stringers or webs do not directly support frames, the stiffeners are to be spaced at about 6 ft (1.83 m). Tripping brackets are to be fitted at intervals of about 10 ft (3 m). Where the breadth of the flange on either side of the stringer or web exceeds 8 in. (200 mm), the brackets are to be arranged to support the flange.

5.7 Special Strengthening

Special consideration is to be given to local strengthening to suit particular operating conditions. Closely-spaced shell webs and stringers are to be arranged forward and aft in those areas which are most subject to dock damage. Suitable fenders are recommended and, where fitted, they are to be supported by decks, stringers, or other internal stiffening.

5.8 Topside Tunnel or Side Tank Structure

The structural members stiffening the side shell, side tank, and freeboard and lower decks are to be of such size as to meet local strength requirements and of such thickness as to be compatible with the plating to which they are attached. Web frames are to be arranged to support the longitudinal members and the arch beams and they are to develop continuity between the arch beams and the structure below the lower deck.


Where constructed of higher-strength steel and provided the steel to which they are attached generally has the same properties, the scantlings given in the preceding paragraphs of Section 5 may be modified as permitted by 5.9.1 and 5.9.2. Higher-strength steel

SECTION 513 Framing

members are to be continuous where they intersect with members of ordinary-strength steel.

5,9.1 Section Modulus The section modulus of each higher-strength steel member is not to be less than obtained from the following equation.

SMht., = (SM)Q

SMhjx = section modulus of higher-strength steel member, in in.3 or cm

SM = section modulus of ordinary-strength steel member, in in.3 or cm3, as required by the preceding paragraphs of this section

Q = as defined in 2.5.2

5.9.2 Plating Where constructed of higher-strength steel, the thickness of string-ers and webs is not to be less than obtained from the following equation.

this = (t c)[(Q 2‘i())/3] c

thickness of higher-strength steel, in in. or mm t = thickness of ordinary-strength steel, in in. or mm, as required

by 5.6.2 for the depth of the web. 0.06 in. (1.5 mm)

Q = as defined in 2.5.2

5.10 Struts

The value of W for struts is not to be less than obtained from the following equation.

W = 0.03bhs long tons W = 1.071ahs metric tons

b = mean breadth, in ft or m, of the area supported h = distance, in ft or m, from the center of the area supported to the

load line, or to a point located at two-thirds of the distance from the top of the tank to the top of the overflow, whichever is greater

s = spacing, in ft or m, of stringers or webs

The sizes of struts are to satisfy the following equation.

W (7.83 — 0.345//r')A long tons W = (1.232 — 0.004521/r')A metric tons

unsupported span of the strut, in ft or cm r' = least radius of gyration, in in. or cm A = area of the strut, in in.2 or cm2

Struts within tanks are to be of solid section. Special attention is to be given to the end connections for tension members.

SECTION 514 Framing

SECTION 6

Watertight Bulkheads

6.1 General

All vessels are to be provided with watertight bulkheads in accord-ance with this section and as outlined by 1.3; in vessels of special type where adherence to these requirements is found to be imprac-ticable, the arrangements will be specially considered. In all cases, the plans submitted are to show clearly the location and extent of the bulkheads. Watertight bulkheads constructed in accordance with these requirements will be recorded in the Record as WT (water-tight), the symbols being prefixed in each case by the number of such bulkheads. Watertight bulkheads which serve as tank boundaries are to have scantlings not less than obtained from Section 7.

6.2 Arrangement of Watertight Bulkheads

6.2.1 Collision Bulkheads Collision bulkheads are to be fitted in all vessels. They are to be approximately 20 ft (6.1 ni) abaft the stem at the load line in vessels 400 ft (122 m) in length and 30 ft (9.15 in) abaft the stem in vessels 1000 ft (305 m) and over in length; values for lengths between 400 ft (122 in) and 1000 ft (305 m) are to be obtained by interpolation. They are to extend to the freeboard deck preferably in one plane, and in vessels with superstructures at the forward end, the bulkheads are to be extended weathertight to the superstructure deck. The extension need not be fitted directly over the bulkhead below provided the part of the freeboard deck which forms the step is made effectively weathertight.

6.2.2 After Peak Bulkheads After peak bulkheads are to be arranged to enclose the shaft tubes in watertight compartments.

6.2.3 Machinery Space Bulkheads are to be fitted at the forward ends of machinery spaces and are to extend to the freeboard deck.

6.3 Chain Lockers

Chain lockers which extend into the forepeak tank are to he made watertight.

SECTION 6 'I Watertight Bulkheads

6.4 Construction of Watertight Bulkheads

6.4.1 Plating Plating is to be of the thickness obtained from Figure 6.1 for the spacing of stiffeners and the distance h measured from the lower edge of the plate to the bulkhead deck at center. The plating of collision bulkheads is obtained from the same Figure using a spacing 6 in. (150 mm) greater than actually adopted. In way of the stern tube, the after peak bulkhead plating is to be increased in thickness, or doubled, to provide suitable support for the tube.

6.4.2 Stiffeners Each stiffener is to have a section modulus SM not less than obtained from the following equation.

SM = 0.0041chs/2 in. SM = 7.0chs12 cm3

c 0.54 for stiffeners between stringers or for stiffeners having bracketed or clipped end connections

= 0.60 for stiffeners having no end attachments h = distance, in ft or m, from the middle oft to the bulkhead deck at

center; where that distance is less than 20 ft (6.1 in), h is to be taken as 0.8 times the distance in ft plus 4 (m plus 1.22)

s = spacing of the stiffeners, in ft or m = span, in ft or m, between supporting stringers or decks or

between the toes of brackets where fitted in accordance with Table 11.2.

The section modulus of stiffeners on collision bulkheads is to be at least 25% greater than required for ordinary bulkheads. Stiffeners on watertight bulkheads in way of the cargo holds are to have end attachments. Stiffening arrangements on the after-peak bulkhead are to he specially considered, particularly in way of the stern tube; additional stiffening may be required to minimize the effect of vibration.

6.4.3 Stringers and Webs a Strength Requirements Each stringer and web which supports

bulkhead stiffeners is to have a section modulus SM not less than obtained from the following equation.

SM = 0.0025chs12 in.3 SM = 4.74chs12 ern3

c = 1.0 h = distance, in ft or m, from the center of the area supported to the

bulkhead deck at center; where that distance is less than 20 ft (6.1 in), the value of h is to be 0.8 times the distance in ft plus 4 (in plus 1.22)

s

sum of half-lengths, in ft or m, (on each side of the stringer or web) of the stiffeners supported

I = span, in ft or m, between bulkheads or webs or between decks or other supports

SECTION 612 Watertight Bulkheads

Where effective brackets are fitted I may be modified as described in Table 11.2.

The section moduli of stringers and webs on collision bulkheads is to be at least 25% greater than required for similar supporting members on ordinary bulkheads.

b Proportions Stringers and webs are to have depths not less than 1 in. per ft (8.4 mm per 100 mm) of span 1. The depth is not to be less than two times the depth of the slots, and the thickness is not to be less than 0.01 in. per in. (1 mm per 100 mm) of depth plus 0.12 in. (3 mm), but need not exceed 0.44 in. (11 um).

c Tripping Brackets Tripping brackets arranged to support the flanges are to be located at intervals of about 10 ft (3 m).

d Attachments Where stiffeners cross decks or bulkheads on the opposite side of the plating, chocks are to be fitted.

6.4.4 Watertight Doors Watertight doors of an approved type are to be of ample strength for the water pressure to which they may he subjected, and fitted with gaskets and dogs spaced and designed to insure that the opening may be closed thoroughly watertight. Those doors below the freeboard deck which may require to be opened at sea are to have either audible or visual alarms located in the pilot house to indicate whether the doors are in the open or closed position. Where stiffeners are cut in way of watertight doors, the openings are to be framed and bracketed so as to maintain the full strength of the bulkhead without taking the strength of the door frames into con-sideration. Where doors are hinged, they are to be quick-acting type. The doors are to be closed and dogs secured at all times except when the vessel is in port or when the door is used for access. Where used at sea for access the door is to be closed and dogs secured immediately access is gained. Signs informing of this requirement are to be posted on either side adjacent to the door.

6.4.5 Testing Testing of watertight bulkheads, recesses, and decks is to he carried out after the completion of all work affecting the watertightness. A hose test is to be carried out under simultaneous inspection of both sides of the plating and the pressure of the water in the hose is not to be less than 30 psi. (2.1 kg/cm2). Shaft tube compartments and forepeaks are to be tested with a head of water to the load line. Where shaft tube compartments and forepeaks are used as tanks, the test heads are not to be less than required in 7.3.


Where constructed of higher-strength steel, the scantlings given in the preceding paragraphs may be modified as permitted by 6.5.1 and 6.5.2.

Care is to be taken to avoid the adoption of reduced thicknesses of members that might be subject to damage during normal operation.

SECTION 6 3 Watertight Bulkheads

Calculations, showing that adequate buckling strength is provided, may be required to be submitted. The structural members and the plating to which they are attached are to generally have the same strength properties.

6.5.1 Section Modulus The section modulus of each higher-strength steel member is not to be less than obtained from the following equation.

= (SM)Q

= section modulus of higher-strength steel member, in TT1.3 or cm3

SM = section modulus of ordinary-strength steel member, in in.3 or ema, as required by the preceding paragraphs of this section

= as defined in 2.5.2

6.5.2 Plating Where constructed of higher-strength steel, the plate thickness required by the preceding paragraphs of this section may be modi-fied but is not to be less than obtained from the following equation.

= (t ± 2V-0)131 c thickness of higher-strength steel, in in. or mm

t = thickness of ordinary-strength steel, in in. or mm, as required by the preceding paragraphs of this section

c = 0.06 in. (1.5 mm) Q = as defined in 2.5.2


FIGURE 6.1 Curves for Watertight Bulkhead Plating Thickness—Inch Units

Spacing, in.

18 21 24 27

Head, ft

0 0.20 25 0.30 0.35 0.40 0.45 0.50 0.55 0.60 0.65

Plating thickness, in.

Note: Curves are based on the following equation

t = (0.0228 -0-;)s + 0.6 in.

s = stiffener spacing, ft h = as defined in 6.4.1

SECTION 6 5 Watertight Bulkheads

25.0

20.0

15.0

10.0

5.0

Head, m

17.5 20.0 15.0

Spacing, m

0>• O• O- O' O. 777

. I ... 0 2.5 5.0 7.5 10.0 12.5

Plating thickness, mm

FIGURE 6.1

Curves for Watertight Bulkhead Plating Thickness—Metric Units


t (3.45 -0i)s + 1.5 mm

s = stiffener spacing in m h = as defined in 6.4.1


SECTION 7

Tank Boundary Bulkheads

7.1 General

All tank boundary bulkheads are to be constructed in accordance with the requirements of this section. Tanks are to be arranged with swash bulkheads in such number and location as to minimize the dynamic stress of the structure. The arrangements of all tanks, together with their intended service and the height of the overflow pipes, are to be clearly indicated on the plans submitted for ap-proval.

7.2 Construction of Tank Boundary Bulkheads

7.2.1 Plating The thickness of the plating is to be obtained from Figure 7.1 for the spacing of the stiffeners with the distance it in ft or m measured from the lower edge of the plating to a point located at two-thirds of the distance from the top of the tank to the top of the overflow. The thickness of plating of side tank bulkheads when subject to mechan-ical damage, and the hopper slopes forming tank boundaries in self-unloading vessels, is to be increased 0.06 in. (1.5

7.2.2 Stiffeners Each stiffener is to have a section modulus S,M not less than obtained from the following equation.

SM = 0.0041chs12 in.3 SM = 7.9chs12 ems

c = 1.0 h = distance, in ft or In, from the middle of / to a point two-thirds of

the distance from the top of the tank to the top of the overflow. The value of h is not to be taken at less than 6 ft (1.83 m).

s = spacing of the stiffeners, in ft or m 1 = span, in ft or m, between stringers or decks or between toes of

brackets where fitted in accordance with Table 11.2.

All stiffeners which pass through decks, girders, or stringers are to be attached to these members, and elsewhere they are to be fitted with brackets or clips which are to extend to the adjacent frame or beam.

7.2.3 Stringers and Webs a Strength Requirements Each stringer and web which supports

stiffeners in deep tanks is to have a section modulus SM not less than

SECTION 71 Tank Boundary Bulkheads

obtained from the following equation.

SM 0.0025chs/ 2 in.3 Slit• = 4. 7 4chs1 2

c = 1.5 h = distance, in ft or m, from the center of the area supported to a

point located at two-thirds of the distance from the top of the tank to the top of the overflow. The value of h is not to be taken at less than 6.0 ft (1.83 m).

s = sum of half lengths, in ft or m, (on each side of the stringer or web) of the stiffeners supported

/ = span, in ft or m, between bulkheads or webs or between decks or other supports

Where effective brackets are fitted, 1 may be modified as described in Table 11.2. Where efficient struts are fitted between stringers or webs, the combined section moduli of the stringers or webs may be used.

b Proportions Stringers and webs are to have depths not less than 1.5 in. per ft (12.6 mm per 100 mm) of span / when no struts or ties are fitted, and 1 in. per ft (8.4 mm per 100 mm) when struts are fitted. The depth is not to be less than 2.5 times the depth of the slots, and the thickness is not to be less than 0.01 in. per in. (1 mm per 100 mm) of depth plus 0.12 in. (3 mm), but need not exceed 0.44 in. (11 mm).

c Tripping Brackets and Web Plate Stiffeners Tripping brackets arranged to support the flanges are to be located at intervals of about 10 ft (3 m). Where the bulkhead may be subject to mechanical damage, flat bars or other web plate stiffeners are to be fitted at each stiffener for the full depth of the stringer or web, and elsewhere they are to be fitted at alternate stiffeners.

7.2.4 Attachments Where stiffeners cross decks or bulkheads on the opposite side of the bulkhead plating, the stiffeners are to be attached to the bulkhead by chocks in line with the deck or bulkhead on the opposite side of the bulkhead.

7.3 Testing

All tanks are to be tested with a head of water to the overflow.

7.4 Topside Tunnel or Side Tank Bulkheads

It is recommended that the uppermost strake of continuous longitu-dinal side tank or tunnel side bulkheads which extend to the free-board deck not be less than 0.44 in. (11 mm) in vessels of 400 ft (122 m) length and 0.62 in. (15.5 mm) in vessels of 700 ft (213 m) length and above. Openings, where cut, are to have well-rounded corners and may require compensation.


7,5 Higher-strength Steel

Where constructed of higher-strength steel, the scantlings given in the preceding paragraphs of this section may be modified as permit-ted by 7.5.1 and 7.5.2. The structural members and the plating to which they are attached are to generally have the same strength properties.

7.5.1 Section Modulus The section modulus of higher-strength steel members is not to be less than obtained from the following equation.

SAS n = (SM)Q

SM = section modulus of higher-strength steel member, in in,3 or CID

SM = section modulus of ordinary-strength steel member, in in.3 or cm3, as required by the preceding paragraphs of Sec-tion 7 as defined in 2.5.2

7,5.2 Plating Where constructed of higher-strength steel, the plate thickness required by the preceding paragraphs of this section may be modi-fied but is not to be less than obtained from the following equation,

thr, = (t 2VQ)/3] c

this = thickness of higher-strength steel, in in. or mm = thickness of ordinary-strength steel, in in. or mm, as required



spacing, in. 18 21 24 27 30

r_O 0.20 0,25 0.30 0.35 0.40 6.45 0.50 0.55 0.60

Plating thickness, in.

FIGURE 7,1

-ves for Tank Bulkhead Plating ckness—Inch Units

Note.- Curves are based on the following equation

t = (0.02792 -0s

s stiffener spacing in ft h = head as defined in 7.2.1

I r)N 7 4 Tank Boundary Bulkheads

FIGURE 7,1

Curves for Tank Bulkhead Plating Thickness—Metric Units

0 15 5.0 7.5 10.0 12.5 Plating thickness, mm


(4.21407)s mm

a = stiffener spacing in ft = head as defined in 7.2.1

15.0 17.5 20.0

SECTION 7(5 Tank Boundary Bulkheads

SECTION

Decks

8.1 General

Strength decks are to be effectively continuous, preferably in one plane; should they change level, the change is to be accomplished by a gradually sloping section or by the deck material at each level being extended so as to provide a suitable overlap and being effectively tied together by diaphragms or webs. All decks exposed to the weather are to be weathertight.

8.2 Testing

Riveted boundaries of weathertight decks are to be subjected to hose testing after all fittings affecting the weathertightness are fastened in position, and the pressure of water in the hose is not to be less than 30 psi (2.1 kg/cm2). Decks forming the top of tanks are to be tested as required by Section 7 and decks forming steps in watertight bulk-heads are to be tested as required by Section 6.

8.3 Plating

8.3.1 Freeboard Deck The exposed plating of the freeboard deck, outboard of the cargo hatchways within the midship 0.67L, is to have the sectional area required for purposes of longitudinal hull-girder strength as required by 2.1 and he of approximately the same thickness as the sheer strake. The stringer plate is to be of sufficient width to extend well inboard of the line of the hatch openings to allow for a generous radius at the corners of the openings, but where the inboard seam is riveted, this requirement may be modified. At the ends of the vessel, the stringer plate thickness is not to be less than the shell plating thickness at ends, see Table 11.1, Column 6. End thicknesses are not to extend for more than 0.1L and are to be gradually tapered to the midship thickness. Local increases in thickness in way of breaks at superstructures may be required and will be subject to special consideration. Exposed plating within the line of the hatch-way openings is to be of the thickness required by Table 8.1, line 1, however, the thickness in way of the arch beams is not to be less than that required to provide an efficient top flange for these members. Within enclosed spaces, the plating thickness within the line of openings is not to be less than required by Table 8.1, lines 2 or 3, for platform decks.

SECTION 811 Decks

8.3.2 Lower Decks a Strength Decks Lower decks which are considered as effective

members of the hull girder (see 2.1) are to be treated as strength decks (see 8.1). The thickness of the plating is not to be less than given in Table 8.1, line 1, or where the deck forms the top of a tank, as required for tank boundary bulkhead plating at that level, see 7.2.1, whichever is greater.

b Platform Decks Lower decks which are not considered to be effective decks for longitudinal strength are termed platform decks. The plating which forms the top of a tank is to he of the thickness required for tank boundary bulkhead plating at that level (see 7.2.1). Elsewhere, the thickness is not to be less than required by Table 8.1, lines 2 or 3, In way of boilers and within coal hunkers, the thickness is to be increased 0.06 in. (1.5 mm). Platform decks which have a length greater than 0. IL are to be fitted with tapering brackets to the shell, the thickness of which may be specially considered.

8.3.3 Superstructure Decks and Tops of Houses a Forecastle and Poop Decks Exposed plating of the forecastle

and poop decks is to be of the thickness required by Table 8.1, line 1, and within enclosed spaces, the thickness is not to be less than given in Table 8.1, lines 2 or 3, for platform decks. Where the length of the forecastle or poop exceeds 0.1L, the thickness of the stringer and adjacent plating beyond 0.1L may be required to be increased. In all cases, the thickness of the stringer plate in way of the forecastle or poop bulkhead is to be specially considered.

b Tops of Houses The plating thickness of the tops of houses is not to be less than required by Table 8.1, line 2, where the house top is at the first level above the freeboard deck, or as required by line 3, where it is at the second level above the freeboard deck, Where deck houses have a length greater than 0.1L, the thickness of deck plating may he required to be increased.

8.3.4 Special Material Requirements Vessels are to have stringer plates of special material in accordance with the -Rules for Building and Classing Steel Vessels". These strakes are to extend throughout the midship 0.67L. Riveted seams as an alternative to the material requirements of this paragraph will be specially considered. See also 4.5.

1.4 Beams

Beams supporting decks which form the tops of tanks are to be of the sizes required for tank boundary bulkhead stiffeners at the same level (see 7.2.2). Elsewhere, each deck beam is to have a section modulus SM riot less than obtained from the following equation.

ECTI N 8 2 Decks

SM = 0.0041chsi 2 in.3 SM = 7.9c1s12 cm3

c = 1.00 for longitudinal beams considered as part of the effective hull girder (see 2.2.k) 0.54 for all other beams

h = 7.0 ft (2.13 m) for beams in way of exposed plating of freeboard and forecastle decks

= 6.0 ft (1.83 m) for beams of the freeboard and forecastle decks within superstructures of deck houses, and for beams of effec-tive lower decks and platform decks in machinery spaces

= 5.0 ft (1.52 m) for beams of the poop deck and for the tops of houses located aft, forming the first level above the freeboard deck

= 4.0 ft (1.22 m) for beams of tops of houses forming the second level above the freeboard deck, and for beams of platform decks outside machinery spaces

= 3.0 ft (0.915 m) for beams of tops of houses forming the third and higher levels above the freeboard deck

s spacing of the beams, in ft or m = span, in ft or m, between girders or deep beams or between

toes of brackets where fitted in accordance with Table 11.2.

8.5 Deep Beams and Girders

8.5.1 Strength Requirements Deep beams and girders are to be so located in relation to webs, bulkheads, etc. as to provide the necessary continuity for the strength and stiffness of the hull. Those located under decks which form the tops of tanks are to he as required for the stringers of tank boundary bulkheads at the same level. Elsewhere, each is to have section modulus SM not less than obtained from the following equation.

SM = 0.0025c.bh/ 2 in.3 SM = 4.74cbh1 2 cm3

c = 1.0 h = sum of the half breadths, in ft or m, of the area supported h = appropriate value for the location as given in 8.4

= span, in ft or m, between bulkheads or stanchions or other supports

Where effective brackets are fitted, 1 may be modified as described in Table 11.2.

8.5.2 Proportions In general, girders and deep beams, except arch beams as given in 8.5.4, are to have depths not less than 0.7 in. per ft (6 mm per 100 mm) of span 1. The depth is to be not less than twice the depth of the slots, and the thickness is not to be less than 0.01 in. per in. (1 mm per 100 mm) of depth, plus 0.12 in. (3 mm), and may be required to be increased in way of concentrated loads.

SECTION 813 Decks

8.5.3 Proportions of Deep Beams and Girders in Tanks Girders and deep beams are to have depths not less than 1 in. per ft (8.4 mm per 100 mm) of span 1. The depth is not to be less than 2.5 times the depth of the slots, and the thickness is not to be less than 0.01 in. per in. (1 mm per 100 mm) of depth plus 0.12 in. (3 mm), but need not exceed 0.44 in. (11 mm).

8.5.4 Arch Beams Each arch beam under the freeboard deck is to have a section modulus SM not less than obtained from the following equation.

SM ..-,_ 0. 0025es/ 2 in SM 4.74cs1 rn3

7.0 ft (2.13 m) s = spacing of arch beams, in ft or m 1

span, in ft or M, between longitudinal bulkheads or between the inboard faces of web frames

Where effective brackets are fitted 1 may he modified as described in Table 11.2.

The depth of arch beams is to be I in, per ft (8.4 mm per 100 mm) of span 1. The web thickness is not to be less than 0.38 in. (9.5 mm) in association with brackets and panel stiffeners spaced 36 in. (915 mm).

.6 Special Heavy Beams and Girders

Special heavy beams and girders are to he arranged as may he required to carry concentrated loads.

.7 Openings

Openings in decks are to he framed so as to provide efficient support and are to have well rounded corners. Access openings in the freeboard deck, such as companionways or trunks, are to be located well within the line of cargo hatchways. Openings in the stringer plate of the freeboard deck for scuppers and air pipes are to he well rounded and smooth, and generally compensation will not be re-quired.

.8 Higher-strength Steel

In general, proposed applications of higher-strength steel for decks are to be accompanied by submission of calculations in support of adequate strength against buckling. Higher-strength steel members are to be continuous at their intersection with those of ordinary-strength steel. Care is to be exercised to avoid the adoption of reduced thicknesses of material such as might be subject to damage during normal operation. The deck supporting members and the deck plating to which they are attached are to generally have the same strength properties and strength decks are to be generally

ECTION 8 4 Decks

longitudinally framed. Subject to the foregoing and compliance with the longitudinal strength requirement of 2,5, the scantlings given in the preceding paragraphs of this section may be modified as permit-ted by 8.8.1 through 8.8.3.

8.8.1 Freeboard Deck Plating Where constructed of higher-strength steel, the plate thickness is to be not less than obtained from the following equation.

t„ = (t c)Q c

thu = thickness of higher-strength steel, in in. or mm t = thickness of ordinary-strength steel, in in. or mm, as required

by 8.3.1 c = 0.06 in. (1.5 mm) Q = as defined in 2.5.2

8.8.2 Lower Decks, Superstructure Decks, Deckhouse Tops, and Girder Webs

Where constructed of higher-strength steel, the plate thickness is not to be less than obtained from the following equation.

this = — 4- 2V(5)/31 c

= thickness of higher-strength steel, in in. or mm t

thickness of ordinary-strength steel, in in. or mm, for which a requirement is given in the preceding paragraphs of this section

c = 0.06 in. (1.5 mm) Q = as defined in 2.5.2

8.8.3 Section Modulus The section modulus of' each higher-strength steel member is not to be less than obtained from the following equation.

SM„= (SM)Q

SAiho = section modulus of higher-strength steel member, in in.3 or cm3

SM section modulus of ordinary-strength steel member, in in.3 or cm3, as required in the preceding paragraphs of this section

Q as defined in 2.5.2

SECTION 8)5 Decks

TABLE 8.1 Minimum Thickness of Deck Plating

Spacing of Longitudinal or Transverse Beams

in. mm

24 27 30 33 36 610 685 760 835 915

0.28 0.31 0.33 0.35 0.37 7.0 8.0 8.5 9.0 9.5

0.25 0.28 0.29 0.30 0.31 6.5 7.0 7.5 8.0 8.0

0.21 0.22 0.24 0.25 0.28 5.5 5.5 6.0 6.5 7.0

1 Freeboard decks within line of hatch openings; exposed forecastle and poop decks; effective lower decks

2 House tops, first

level above free-board deck; plat-form decks within enclosed cargo or machinery spaces

3 Platform decks within enclosed passenger or crew spaces; house tops at second level above freeboard deck

SECTION 8 6 Decks

SECTI©N 9

Superstructures and Deckhouses

9.1 Superstructures

9.1.1 Side Plating The thickness of side plating of the poop and forecastle is not to he less than given in Table 11.1, Column 7, for a distance of 0.1L from the ends of the vessel; beyond 0. IL, the thickness is to be gradually increased. In way of the forecastle and poop bulkheads, a further increase may he required. The plating is to be carried well beyond the end bulkheads and fashioned so as to provide a long gradual taper to the sheerstrake. Where the plating is welded to the sheerstrake, the termination of the joint is to be ground smooth and faired into the top edge of the sheerstrake.

9.1.2 Side Frames The side frames of the poop and forecastle are to be aligned with the frames below the freeboard deck. Each frame abaft the collision bulkhead is to have a section modulus SM not less than obtained from the following equation.

SM = 0.0041cs/ in.a SM = 7.9es12 em3

c = for forecastle side frames abaft the collision bulkhead 20 (6,1) for vessels 400 ft (122 m) in length

• 30 (9.15) for vessels 800 ft (244 m) or over in length c

▪

for poop side frames 16 (4.9) for vessels 400 ft (122 in) in length 24 (7.3) for vessels 800 ft (244 m) or over in length

Intermediate values of c are to he obtained by interpolation.

s = spacing of the frames, in ft or m I = span, in ft or rn, between decks or between toes of brackets

where fitted in accordance with Table 11.2

Forecastle side frames forward of the collision bulkhead are to be of' the same size as those abaft, are to be aligned with each frame below the freeboard deck, and are to he bracketed to the deck beams. Web frames or partial bulkheads are to he lilted over main bulkheads or webs as may be required to provide adequate trans-verse rigidity to the superstructures.

9.1.3 Decks The thickness of plating on superstructure decks is to be in accord-

SECTION 911 Superstructures and Deckhouses

ance with the requirements of 8.3.3a. Deck beams and girders are to be as required by 8.4, 8.5, and 8.6

9.1A Superstructure Bulkheads and Deckhouse Bulkheads on Freeboard Deck

a Plating The plating is to be not less in thickness than obtained as follows.

0.38 in. (9.5 mm) for poop front and deckhouse front bulkheads 0.30 in. (7.5 mm) for deckhouse sides and after bulkhead, poop and forecastle after bulkheads Where the spacing of stiffeners is greater or less than 30 in. (760 mm), the thickness is to be increased, or may be reduced, at the rate of 0.02 in. for each 4 in. (0.5 mm per 100 mm) difference in spacing, respectively.

b Stiffeners Each stiffener is to have section modulus SM not less than obtained from the following equation.

SM 0.0041cs12 in.3 SM 7.9cs/ 2 cm3

c = 10 (3) at L = 400 ft (122 m) and 14.5 (4.4) at L n 500 ft (152 m) for poop front and deckhouse front bulkheads. Intermediate values may be obtained by interpolation.

= 4.75 (1.45) for deckhouse sides = 4.0 (1.22) for poop and deckhouse after bulkheads = 3.4 (1,04) for forecastle after bulkhead

s = spacing of stiffeners, in ft or m 1 = 'tween deck height, in ft or m

Stiffeners on the poop front or deckhouse front bulkheads are to be attached to the decks at their ends, and elsewhere they may have sniped ends.

9.1.5 Windlass Room Bulkhead Where the anchor windlass is located on the freeboard deck, a bulkhead is to be fitted abaft the windlass and is to have the scantlings required for forecastle bulkheads. See also 6.2.1.

9.2 Deckhouses on Superstructure Decks

9.2.1 Bulkheads a Plating The plating is to be not less in thickness than obtained

as follows.

0.30 in. (7.5 mm) for deckhouse fronts 0.28 in. (7.0 mm) for deckhouse sides 0.25 in. (6.5 mm) for deckhouse after ends

Where the spacing of stiffeners is greater or less than 30 in. (760 mm), the thickness is to be increased, or may be reduced, at the rate of 0.02 in. for each 4 in. (0.5 mm per 100 mm) difference in spacing, respectively.


b Stiffeners Each stiffener is to have section modulus SM not less than obtained from the following equation.

SM = 0. 0041cs/ 2 in.a SM = 7.9cs/2 ema

7.5 (2.29) at L = 400 ft (122 m) and 10.0 (3) at L 500 ft (152 m) for house front bulkhead on forecastle deck. Inter- mediate values may be obtained by interpolation. 7.5 (2.29) for house front bulkhead on poop deck 4.5 (1.37) for house sides on forecastle deck 4.0 (1.22) for house sides on poop deck

= =_ 3.4 (1.04) for house after bulkheads s, 1 = as defined in 9.1.4h

Stiffeners on the house front bulkheads are to be attached to the decks at their ends, and elsewhere they may have sniped ends.

9.2.2 Stacks Partially protected stacks and other structures located on the first deck above the freeboard deck and which enclose openings leading to spaces below are to have scantlings not less than as required for the after bulkheads of houses.

9.2.3 House Tops The plating for the tops of deck houses is to be in accordance with the requirements of 8.3.3b. Beams and girders are to be as required by 8.4, 8.5, and 8.6.

9.3 Openings

Where openings are cut in bulkheads for access and other purposes, they are to have rounded corners and are to be so framed as to maintain the strength of the bulkhead.


In general, proposed applications of higher-strength materials for superstructures and deckhouses are to meet the requirements of this section, but may be modified as permitted by 9.4.1 through 9.4.3. Care is to be taken to avoid the adoption of reduced thicknesses of members that might be subject to damage during normal operation. Calculations, showing that adequate buckling strength is provided, may be required to be submitted. The structural members and the plating to which they are attached are to generally have the same strength properties.

9.4.1 Section Modulus The section modulus of each higher-strength steel member is not to be less than obtained from the following equation.


{SA/ )(2

= section modulus of higher-strength steel member, in in.3 car

cm3 SM = section modulus of ordinary-strength steel member, in in.3

or cm3, as required by the preceding paragraphs of this section as defined in 2.5.2

9.4.2 Deck Plating Where constructed of higher-strength steel, the thickness of super-structure decks and deckhouse tops is to be in accordance with the requirements of 8.8.2.

9.4.3 Side and Bulkhead Plating Where constructed of higher-strength steel, the thicknesses of superstructure sides and of the superstructure and deckhouse bulk-heads, as required by the preceding paragraphs of this section, may be modified but are not to be less than obtained from the following equation.

= (t c)[(Q 2V45)/3] c

th„. = thickness of higher-strength steel, in in. or mm t = thickness of ordinary-strength steel, in in. or mm, as required



SECTION 1 U

Equipment

10,1 General

All vessels are to have a complete equipment of anchors and chains. The symbol 0 included in the classification symbols as published in the Record will signify that the equipment is in compliance with these requirements and has been tested in the presence of the Surveyors to this Bureau in accordance with the requirements of Section 43 of the "Rules for Building and Classing Steel Vessels". Chains which are intended to form part of the equipment are not to be used as check chains when the vessel is launched. Anchors and their chains are to be effectively secured and arrangements for stopping each chain as it is paid out are to be provided. The windlass is to be capable of heaving in either chain and suitable arrangements for securing the anchors and stowing the chains are to be provided.

10.2 Equipment Weight and Size

Each vessel is to be provided with two bower anchors (stockless) and 180 fathoms (330 m) [90 fathoms (165 m) on each anchor], the weights and sizes of these being in accordance with Table 10.1 and regulated by the tonnage for equipment as obtained from the following equations. Anchors of other types and chains of other material will be specially considered. Where the calculated tonnage falls between two values given in the Table, the lower value may be used.

Tonnage under freeboard deck = 0.01cLBD inch units 0.35cLBD metric units

c =0.85 L = length of vessel as defined in 1.8.1, in ft or m B = breadth of vessel as defined in 1.8.2, in ft or m D depth of vessel to freeboard deck, in ft or m

Addition for superstructures or deck houses on freeboard deck = 0.0066c/bd inch units

0.2355c1bd metric units

c = 0.75 / = length of superstructure or deck house, in m or ft b mean breadth of superstructure or deck house, in m or ft d = mean height of superstructure or deck house, in m or ft

For the second tier of houses or superstructures the multiplier is to be 0.005 (0.1766) instead of 0.0066 (0,23.55).

SECTION 1011 Equipment

10.3 Tests

Tests are to be in accordance with the Table requirements for the respective sizes as set forth in Section 43 of the "Rules for Building and Classing Steel Vessels". Anchors and chains are to be tested in an approved machine in the presence of a Surveyor.

10.4 Anchor Types

Anchors are to be of the stockless type in which the weight of the head is not less than three-fifths of the total weight of the anchor. Where specifically requested by the Owners, the Bureau is prepared to give consideration to the use of special types of anchors and where these are of proven superior holding ability, consideration may also be given to some reduction in the weight, up to a maximum of 20%, from the weight specified in Table 10.1. In such cases an appropriate notation will be made in the Record.

10.5 Hawsers, Towlines, Stern Anchor, and Chain

Hawsers, towlines, stern anchor, and chain are not required as a condition of classification. However, the attention of Owners, builders, and designers is called to the requirements of the various authorities or underwriters with respect to stern anchor and tow-lines.

.106 Windlass

The windlass is to be of good and substantial make, suitable for the size of chain required by Table 10.1. Care is to be taken to insure a fair lead for the chain from the windlass to the hawse pipes and to the chain pipes. The windlass foundation and deck supporting arrange-ments are to be specially considered.

10.7 Hawse Pipes and Anchor Pockets

Hawse pipes and anchor pockets are to he of ample size and strength. They are to be secured to thick plating and, after installa-tion, are to be hose tested for watertightness, with the pressure of the water in the hose not to he less than 30 psi (2.1 kgicinz). The hawse pipes are to have the easiest possible lead and full round flanges so as to minimize the nip on the chains. The anchors are to be shipped and unshipped so that the Surveyor may be satisfied that there is no risk of the anchors jamming in the hawse pipes or anchor pockets.

SECTION 10 2 Equipment

Equipment Tables

TABLE 10.1

Equipment Weights and Sizes

Inch/Pound Units Chain Cable

Stud Link Bower Chain

Equipment Tonnage

Weight Each

Anchor lb

Diameter

Normal- Strength

Steel (Grade I)

in,

High- Strength

Steel (Grade 2)

in.

Extra High- Strength

Steel (Grade 3).

in.

2000 3750 15/8 17/16 11/4 2500 4000 15/8 17/16 11/4 3000 4500 13/4 11/2 15/16 3500 4750 17/8 15/8 17/16 4000 5000 115/1s 111/16 17/16

4500 5250 2 13/4 11/2 5000 5750 21/16 113/16 13/16 5500 6000 91/16 113/16 19/16 6000 6300 21/16 113/i6 19/16 6500 6500 216,6 112/16 13/16

7000 6750 21/s 17/a 15/s

7500 7000 21/s 17/8 15/8 8000 7250 21/8 17/8 15/8 8500 7250 23/16 115/16 13/4 9000 7600 23/16 115/16 13/4

9500 7600 25/16 2 1'3/16 10000 8100 25/16 2 113/16 10750 8600 25/16 2 113/16 11500 8600 23/8 21/16 115/16 12250 9000 23/8 21//6 115/16

13000 9000 27/16 21/s 17/s 13750 9500 27/16 21/s 17/8 14500 10000 27/16 21/s 17/8 15250 10000 21/2 23/16 2. 16000 10000 21/2 23/16 2

16750 10000 21/2 23/16 2 17500 11000 23/16 21/4 2 18250 11000 nin 21/4 2 19000 11000 23/16 21/4 2

19750 11000 25/8 25/16 2

20500 12000 25/6 25/16 2

21250 12000 211/16 23/8 21/16 22000 12000 211/16 23/8 21/16 23000 13000 2"/1.6 23/6 21/16 24000 13000 23/4 27/16 21/8


TABLE 10.1 (continued)

Inch/Pound Units Chain Cable


Equipment Tonnage

Weight Each

Anchor lb

Diameter

Normal- Strength

Steel (Grade 1 }

in.

High- Strength

Steel (Grade 2)

in.


Steel (Grade 3),

in,

25000 13000 23/4 27/16 21/8

26000 14000 23/4 27116 21/8

27000 14000 27/6 21/2 23/16

28000 14000 27/6 91/2 23/16

29000 1.5000 2718 2112 nia

30000 15000 215/16 29/16 21/4

31500 16000 215/16 29/16 2114

33000 16000 215/16 29/16 2114

34500 16000 3 25/8 25/16

36000 18000 3 25/8 25/16

37500 1.8000 3 25/8 25/16

39000 18000 3 25/8 25/16

40500 18000 31/16 211/i6 23/6

42000 20000 31/16 211/16 23/6

44000 20000 31/16 211/16 23/8

46000 20000 33/16 23/4 27/16

46000 20000 33/16 23/4 21/16

50000 22500 33/1.6 23/4 27/16

52000 22500 3114 213/16 27/16

54000 22500 35/16 27/8 21/3

56000 25000 35/16 27/6 21/2

58000 25000 35/16 21/6 21/2

60000 25000 33/8 215/1_6 29/16

62000 25000 33/s 215/16 29/16

64000 27500 33/s 215/16 29/16

66000 27500 33/s 215/16 29/16

68000 27500 37/16 3 25/s

70000 27500 37/16 3 25/6


Equipment Weights and Sizes

Metric Units Chain Cable


Equipment Tonnage

Weight Each

Anchor kg

Diameter

Normal- Strength

Steel (Grade 1)

mm

High- Strength

Steel (Grade 2)

mm


Steel (Grade 3),

mm

2000 1700 42 36 32 2500 1815 42 36 32 3000 2040 44 38 34 3500 2155 48 42 36 4000 2270 49 43 36

4500 2380 50 44 38 5000 2610 52 46 40 5500 2720 52 46 40 6000 2860 52 46 40 6500 2950 52 46 40

7000 3060 54 48 42 7500 3175 54 48 42 8000 3290 54 48 42 8500 3290 56 50 44 9000 3445 56 50 44

9500 3445 58 50 46 10000 3675 58 50 46 10750 3900 58 50 46 11500 3900 60 52 46 12250 4080 60 52 46

13000 4080 62 54 48 13750 4310 62 54 48 14500 4535 62 54 48 15250 4535 64 56 50 16000 4535 64 56 50

16750 4535 64 56 50 17500 4990 65 57 50 18250 4990 65 57 50 19000 4990 65 57 50 19750 4990 66 58 50

20500 5445 66 58 50 21250 5445 68 60 52 22000 5445 68 60 52 23000 5895 68 60 52 24000 5895 70 62 54

SECTION 10 6 Equipment

TABLE 10.1 (continued)

Metric Units Chain Cable


Diameter

Equipment Anchor (Grade 1) (Grade 2) (Grade 3), Tonnage kg mm mm mm

Normal- High- Extra High- Weight Strength Strength Strength Each Steel Steel Steel

25000 5895 70 62 54 26000 6350 70 62 54 27000 6350 73 64 56 28000 6350 73 64 56 29000 6805 73 64 56

30000 6805 75 65 57 31500 7260 75 65 57 33000 7260 75 65 57 34500 7260 76 66 58 36000 8165 76 66 58

37500 8165 76 66 58 39000 8165 76 66 58 40500 8165 78 68 60 42000 9070 78 68 60 44000 9070 78 68 60

46000 9070 81 70 62 48000 9070 81 70 62 50000 10205 81 70 62 52000 10205 83 71 62 54000 10205 84 73 64

56000 11340 84 73 64 58000 11340 84 73 64 60000 11340 86 75 65 62000 11340 86 75 65 64000 12475 86 75 65

66000 12475 86 75 65 68000 12475 87 76 66 70000 12475 87 76 66


SECTION 1 1

Tables of Scantlings

SECTION 1 1 j 1 Tables of Scantlings

L L

N

Ot1

33

S

N

sou!

pueo

s 4o

sam

ei

TABLE 11.1

Scantlings-Inch Units

1 2 3 4 5 6 7 8 9 Length Basic Bottom Immersed Shell Forecastle Floors .&.

of of Basic Design & Side Box & Stern at and Center Side Vessel Depth Draft Shell Plating Ends Poop Sides Keelson Keelso YE

See See Notes :1 ote 1-7 8

400 26.67 16.0 0.40 0.45 0.42 0.36 331/2 x 0.42 0.30 410 26.97 16.4 0.41 0.45 0.42 0.36

0.36 341/4 x 0.42 0,30

0.31 0.31

420 27.27 16.8 0.42 0.46 0.42 0.42

343/4 x 0.43 27.56 430 17.2 0.43 0.46 0.36 351/2 x 0.43

440 27,85 17.6 0.44 0.47 0.42 0.36 36 x 0.44 0.32

450 28.13 18.0 0.45 0.47 0.42 0,36 363/4 x 0.44 0.32 460 28.40 18.4 0.46 0.47 0.43 371/2 x 0.44 0.32

0.43 470 28.66 18.8 0.47 0.48 38 x 0.45 0.33 480 28.92 19.2 0.48 0.48

(it-3).13:1777

383/4 x 0.45 0.33 0.49

0.43 0.34 490 29,17 19.6 0.48 0.37 391/4 x 0.46

500 29.41 20.0 0.50 0.49 0.43 0.37 0.37

40 x 0.46 0.34

510 29.65 20.4 0.50 0.49 0.43 403/4 x 0.46 0.34 520 29.89 2 0.49 0.8 0.51 0.44 0.38 411/4 x 0.47

(()).3355 530 30.11 21.2 0.52 0 0.38 .49 0.44 42 x 0.47

540 30.34 21.6 0.53 0.50 0.44 0.38 421/2 x 0.48 0.36

550 30.56 22.0 0.54 0.50 0.44 0.38 0. 44 0.38

431/4 x 0.48 (1)).3366 560 30.77 22.4 0.55 0.51 44 x 0.48

570 30.98 22.8 0.56 0.51. 0.45 0.45

0.39 441/2 x 0.49 0.37

580 31.18 23.2 0.57 0.52 0.39 451/4 x 0.49 0.37

590 31.38 23.6 0.58 0.52 0.45 0.39 453/4 x 0.50 0.38

SE

CT

ION

1 1 13

T

ab

les of S

cantlin

gs

600 31,58 24.0 0.59 0.53 0.45 0.39 461/2 x 0,50 0.38 610 31.77 24,4 0.60 0.53 0.45 0.39 471/4 x 0,50 0.38 620 31.96 24.8 0.61 0.53 0.46 0.40 473/4 x 0.51 0.39 630 32.14 25.2 0.62 0.54 0.46 0.40 481/2 x 0.51 0,39 640 32.32 25.6 0.63 0.54 0.46 0.40 49 x 0.52 0.40

650 32.50 26.0 0.64 0.54 0.46 0,40 493/4 x 0.52 0.40 660 32.67 26.4 0.65 0.55 0.46 0.40 501/2 x 0.52 0.40 670 32.84 26,8 0.66 0.55 0.47 0.41 51 x 0,53 0.41 680 33.01 27.2 0.67 0.55 0.47 0.41 513/4 x 0.53 0.41 690 33.17 27.6 0.68 0.56 0.47 0.41 521/4 x 0.54 0.42

700 33.33 28.0 0.69 0.56 0.47 0.41 53 x 0,54 0.42 710 33.81 28.0 0.69 0.57 0.47 0.41. 531/4 x 0.54 0.42 720 34.29 28.0 0.70 0.57 0.48 0.42 531/2 x 0.55 0.43 730 34.76 28.0 0.71 0.58 0.48 0.42 533/4 x 0.55 0.43 740 35.24 28.0 0.72 0,58 0.48 0.42 54 x 0.56 0.44

750 35.71 28,0 0.73 0.58 0.48 0.42 541/4 x 0.56 0,44 760 36,19 28.0 0.74 0.59 0.48 0.42 541/2 x 0.56 0.44 770 36.67 28.0 0.75 0.59 0.49 0.43 543/4 x 0.57 0.45 780 37.14 28.0 0.76 0.59 0.49 0.43 55 x 0,57 0.45 790 37,62 28.0 0.77 0.60 0.49 0.43 551/4 x 0.58 0.46

800 38.10 28.0 0.78 0.60 0.49 0.43 551/2 x 0.58 0.46 810 38.57 28.0 0.79 0.60 0.49 0.43 553/4 x 0.58 0.46 820 39.05 28.0 0.80 0.61 0.50 0.44 56 x 0.59 0.47 830 39.52 28.0 0.81 0.61 0.50 0.44 561/4 .x 0.59 0.47 840 40.00 28.0 0.82 0.61 0.50 0.44 561/2 x 0.6() 0.48

850 40.48 28.0 0.83 0.62 0.50 0.44 563/4 x 0.60 0.48 860 40.95 28.0 0.84 0.62 0.50 0.44 57 x 0.60 0.48 870 41.43 28.0 0.85 0.62 0.50 0.44 571/4 x 0.61 0.49 880 41.90 28.0 0.86 0.62 0.50 0.44 571/2 x 0.6I 0.49 890 42.38 28.0 0.87 0.62 0.50 0.44 573/4 x 0.62 0.50

pri

L L

NO

LL

OB

S

Oup

ueo

s 10

san

e'

TABLE 1 1 .1 (continued)

1 2 3 4 5 6 7 8 9 Length Basic Bottom Immersed Shell Forecastle Floors &

of Basic Design & Side Box & Stern at and Center Side Vessel Depth Draft Shell Plating Ends Poop Sides Keelson Keelson

See Notes 1-7

See Note

8

900 42,86 28.0 .0.88 0.62 0.50 0.44 58 x 0.62 0.50 910 43.33 28.0 .0.88 0.62 0.50 0.44 581/4 x 0.62 0.50 920 43.81 28.0 .0,89 0.62 0.50 0.44 58'12 x 0.62 0.50 9.30 44.29 28.0 .0.90 0.62 0.50 0.44 583/4 x 0.62 0.50 940 44.76 28.0 •0.91 0.62 0.50 0.44 59 x 0.62 0.50

950 45.24 28.0 •0.92 0.62 0.50 0.44 591/4 x 0.62 0.50 960 45.71 28.0 •0.93 0.62 0.50 0.44 591/2 x 0.62 0,50 970 980

46.19 46.67

28.0 28.0

•0.94 .0,95

0.62 0.62

0.50 0.50

0 0..4444 593/4 x 0.62 60 x 0.62

0.50 0.50

990 47.14 28.0 .0.96 0.62 0.50 0.44 601/4 x 0.62 0.50

1000 47.62 28.0 .0.97 0.62 0.50 0.44 601/2 x 0.62 0.50 1100 52.38 28.0 .0.97 0,62 0.50 0.44 603/4 x 0.62 0.50 1200 57.14 28.0 .0.97 0.62 0.50 0.44 61 x 0.62 0.50

•The tabular thickness for side shell plating for vessels 900 ft and over in length may be taken as 0.88 in.

SE

CT

ION

1 115 T

able s of S

cantling

s

Notes 1 Frame Spacing Correction Where the spacing of transverse or

longitudinal frames is less than 36 in. the thickness of shell plating within 0.67L may be reduced 0.01 in. for each in. of decrease in spacing.

2 Depth Correction Where the depth of vessel is greater than the basic depth, col. 2, the thickness of bottom and side plating may be reduced at the rate of 0.005 in. for each additional ft of depth in excess of the tabular value.

3 Draft Correction The thickness of bottom and side plating is to be increased 0.01 in. for each ft of draft in excess of the basic, draft, col. 3.

4 Transverse Framing Correction Where the bottom shell is trans-versely framed, the thickness of bottom plating imd the spacing of side keelsons is to be specially considered.

5 Minimum Thickness The thickness t„,I„ of shell plating within 0.67L amidships, after all corrections have been made, is not to be less than obtained from the following equation.

= at/36 in.

= thickness from Col. 4. = spacing of frames not to he taken as less than 36 in. at

L = 400 ft 30 in. at L 1000 ft, intermediate values to be obtained by interpolation.

Where the bottom shell is transversely framed, the minimum thick-ness of bottom plating is to be specially considered taking into account the buckling characteristics of the bottom shell plating.

6 Bilge Plating The thickness of the bilge plating is to be in all cases 0.06 in. greater than the thickness required for the bottom shell plating.

7 Longitudinal Bulkheads Where continuous longitudinal side tank bulkheads are not fitted between the freeboard deck and the bottom shell, the thickness of side shell plating is to be increased 0.04 in.

8 Center Keelson Where drafts exceed the basic draft, col. 3, the depth of center keelson is to be increased at the rate of 1 in. per ft of excess draft.

SE

CT

I ON

1 116

Ta

ble

s of S

cantlin

gs

TABLE B.1

Scantlings-Metric Units

1 2 3 4 5 6 7 8 9 Length Basic Bottom immersed Shell Forecastle Floors &

of Basic Design & Side Bow & Stern at and Center Side Vessel Depth Draft Shell Plating Ends Poop Sides Keelson Keelson

m in m mm mm mrn mm eon mm

See Notes

1-7

See Note

8

122 8.13 4.88 10.0 11.5 10.5 9.0 850 x 10.5 7.5 125 8.22 5.00 10.5 11.5 10.5 9.0 870 x 10.5 7,5 128 8.31 5,12 10.5 11.5 10.5 9.0 885 x 11.0 8.0 131 8.40 5,24 11.0 11.5 10.5 9.0 900 x 11.0 8.0 134 4.49 5.36 11.0 12.0 10,5 9.0 915 x 11.0 8.0

137 8.57 5.49 11.5 12.0 10.5 9.0 935 x 11.0 8.0 140 8.66 5.61 11.5 12.0 11.0 9.5 950 x 11.0 8.0 143 8.74 5.73 12.0 12.0 11.0 9.5 965 x 11.5 8.5 146 8,81 5.85 12,0 12.0 11.0 9.5 985 x 11.5 8.5 149 8.89 5.97 12.5 12.0 11,0 9.5 995 x 11.5 8,5

152 8.96 6.10 12.5 12.5 11.0 9.5 1015 x 11.5 8.5 155 9.04 6.22 12.5 12.5 11.0 9.5 1035 x 11.5 8.5 158 9.11 6.34 13.0 12.5 11.0 9.5 1050 x 12.0 9.0 162 9.18 6.46 13.0 12.5 11.0 9.5 1065 x 12.0 9.0 165 9.25 6.58 13.5 12.5 11.0 9.5 1080 x 12.0 9.0

168 9.31, 6.71 13.5 12.5 11.0 9.5 1100 x 12,0 9.0 171 9.38 6.83 14.0 13.0 11.0 9.5 1120 x 12.0 9.0 174 9.44 6.95 14.0 13.0 11.5 10.0 1130 x 12.5 9.5 177 9.50 7.07 14.5 13.0 11.5 10.0 1150 x 12.5 9.5 180 9.56 7.19 14.5 13.0 11.5 10,0 11.60 x 12.5 9.5

SECTIO

N 1

118 T

abl es of S

cantlin

gs


1 2 3 4 5 6 7 8 9 Length Basic Bottom Immersed Shell Forecastle Floors &

of Basic Design d1 Side Box & Stern at and Center Side Vessel Depth Draft Shell Plating Ends Poop Sides Keelson Keelson

m an m mm men Min mm nun mm

See See Notes Note 1-7 8

274 13.06 8.53 •22.5 15.5 12.5 11.0 1475 x .15.5 12.5 277 13.2.1 8.53 •22.5 15.5 12.5 11.0 1480 x 15.5 12.5 280 13.35 8.53 •22.5 15.5 12.5 11.0 1483 x 1.5.5 12.5 283 13.50 8.53 •23.0 15.5 12.5 11-.0 1490 x 15.5 12.5 286 13.64 8.53 .23.0 15.5 12.5 11.0 1500 x 15.5 12.5

290 13.79 8.53 •23.,5 15.5 12.5 .11.0 1505 x 15.5 .12.5 293 13.93 8.53 .23.5 15.5 12.5 11.0 151.0 x 15.5 1.2.5 296 14.08 8.53 .24.0 15.5 12.5 11.0 1520 x 15.5 12.5 299 14.22 8.53 •24.0 15.5 12.5 11.0 1525 x .15.5 1.2.5 302 14.37 8.53 .24.5 15.5 12.5 11.0 1530 x 15.5 12.5

305 .14.51 8.53 .24.5 15.5 12.5 11.0 1535 x 15.5 12.5 335 15.96 8.53 .24.5 15.5 12.5 11.0 1545 x 15.5 12.5 366 17.42 8.53 •24.5 15.5 12.5 11.0 1550 x 15.5 12.5

•The tabular thickness for side shell plating for vessels 274m and over in length may be taken as 22.5mra

s6u!

Rueo

s la

san

e." L

IL t

183 9.63 7.31 15.0 13.5 11.5 10.0 1180 x 12.5 9.5 186 9.68 7.44 15.0 13.5 11.5 10.0 1200 x 12,5 9.5 189 9.74 7.56 15.5 13.5 11.5 10.0 1215 .x 13.0 10,0 192 9.80 7,68 15.5 13.5 11.5 10.0 1230 x 13,0 10.0 195 9.85 7.80 16.0 13,5 11.5 10.0 1245 x 13.0 10.0

198 9.91 7.92 16.5 13,5 11.5 10.0 1265 x 13,0 10.0 201 9.96 8.05 16.5 14.0 11.5 10.0 1285 x 13.0 10.0 204 10,01 8.17 17.0 14.0 12.0 10.5 1295 x 13.5 10.5 207 10.06 8.29 17.0 14.0 12.0 10.5 1315 x 13.5 10.5 210 10.11 8.41 17.5 14.0 12.0 10.5 1325 x 13.5 10.5

213 10.16 8.53 17.5 14.0 12.0 10.5 1345 x 13.5 10.5 216 10.3 8.53 17.5 14.5 12.0 10.5 1355 x 13.5 10.5 219 10.45 8.53 18.0 14,5 12.0 10.5 1360 x 14.0 11.0 222 10.59 8.53 18.0 14.5 12.0 10.5 1365 x 14.0 11.0 226 10.74 8,53 18.5 14.5 12.0 10.5 1370 x 14.0 11.0

229 10.88 8,53 18.5 14.5 12.0 10.5 1380 x 14.0 11.0 232 11.03 8.53 19.0 15,0 12.0 10.5 1385 x 14.0 11,0 235 11.18 8.53 19.0 15.0 12.5 11.0 1390 x 14.5 11.5 238 11.32 8.53 19.5 15.0 12.5 11.0 1395 x 14.5 11.5 241 11.47 8.53 19.5 15.0 12.5 11.0 1405 x 14.5 11,5

244 11.61 8.53 20.0 15.0 12.5 11.0 1410 x 14,5 11,5 247 11.76 8.53 20.0 15.0 12.5 11.0 1415 x 14.5 11.5 250 11,90 8,53 20.5 15.5 12.5 11.0 1420 x 15,0 .12.0 253 12.05 8.53 20.5 15.5 12.5 1.1,0 1430 x 15.0 12.0 256 12.19 8.53 21.0 15.5 12.5 11.0 1435 x 15.0 12.0

259 12.34 8.53 21.0 15.5 12,5 11.0 1440 x 15.0 12.0 262 12.48 8.53 21.5 15.5 12.5 11.0 1450 x 15.0 12.0 265 12.63 8.53 21.5 15.5 12.5 11.0 1455 x 15.5 12.5 268 12.77 8,53 22.0 15.5 12.5 11.0 1460 x 15.5 12.5 271 12.92 8.53 22.0 15.5 12.5 11.0 1465 x 15.5 12.5

SE

CT

ION

1119

Tabl e

s of S

cantlin

gs

Notes 1 Frame Spacing Correction Where the spacing of transverse or

longitudinal frames is less than 915 mm the thickness of shell plating within 0.67L may be reduced 1,0 mm for each 100 mm of decrease in spacing,

2 Depth Correction Where the depth of vessel is greater than the basic depth, col. 2, the thickness of bottom and side plating may be reduced at the rate of 0.04 mm for each additional 100 MITI of depth in excess of the tabular value.

3 Draft Correction The thickness of bottom and side plating is to be increased 0.09 min for each 100 rum of draft in excess of the basic draft, col. 3,

4 Transverse Framing Correction Where the bottom shell is trans-versely framed, the thickness of bottom plating and the spacing of side keelsons is to be specially considered.

5 Minimum Thickness The thickness t„a„ of shell plating within 0. 67L amidships, after all corrections have been made, is not to be less than obtained from the following equation.

= st-i9I5 nun

t = thickness from Col. 4. s spacing of frames not to be taken as less than 915 nun at

L = 122 in and 760 nun at L 305 rfl; intermediate values to be obtained by interpolation.

Where the bottom shell is transversely framed, the minimum thick-ness of bottom plating is to he specially considered taking into account the buckling characteristics of the bottom shell plating.

6 Bilge Plating The thickness of the bilge plating is to be in all cases 1..5 min greater than the thickness required for the bottom shell plating.

7 Longitudinal Bulkheads Where continuous longitudinal side tank bulkheads are not fitted between the freeboard deck and the bottom shell, the thickness of side shell plating is to be increased 1.0 min,

8 Center Keelson Where drafts exceed the basic draft, col. 3, the depth of center keelson is to be increased at the rate of 8.4 mm per 100 rum of excess draft.

TABLE 11.2

Thickness and Flanges of Brackets

Where, brackets at end connections of girders, webs and stringers are fitted having thicknesses not less than the girder or web plates, the value fort may be modified in accordance with the f011owing

Where the face area on the bracket is not less than one-half that on the girder or web and the face bar or flange on the girder or web is carried to the bulkhead or base, the length 1 may be measured to a point 6 in. (150 mm) on to the bracket.

Where the face area on the bracket is less than one-half that on the girder or web and the Lee bar or flange on the girder or web is carried to the bulkhead or base, 1 may be measured to a point where the area of the bracket and its flange, outside the line of the girder or web, is equal to the flange area on the girder.

Where the flange area of the girder or web is carried along the Eire of the bracket, which may be curved for the purpose, 1 may be measured to the point of the bracket.

Brackets are not to be considered effective beyond the point where the length of arm on the girder or web is P/2 times the length of the arm on the bulkhead or base; in no case is the allowance in 1 at either end to exceed one-quarter of the overall length of the girder or web.

Brackets are not to be considered effective beyond the point where the depth of longer arm exceeds 11/2 times the depth of the shorter arm.

Inches Depth

of Longer

Arm

6.0 7.5

Thickness Width

Flange Plain

0.26 0.28

Flanged

9.0 0.30 0.26 l'/4 10.5 0.32 0.26 11/4 12.0 0.34 0.28 1'/2

13.5 0.36 0.28 3-V2 15.0 0.38 0.30 13/4 16.5 0.40 0.30 13/4 18.0 0.42 0.32 2 19.5 0.44 0.32 2

21.0 0.46 0.34 21/4 22.5 0.48 0.34 21/4 24.0 0.50 0.36 21/2 23.5 0.36 21/2 27.0 0.38 23/4

28.5 0.38 23/4 30.0 0.40 3 33.0 0.42 31/4 36.0 0.44 3112 39.0 0.46 33/4

42.0 0.48 4 45.0 0.50 4Y4

SECTION 11110 Tables of Scantlings


Millimeters Depth

of Longer

Arm

150 175

Thickness Width of

Flange Plain

6.5 7.0

Flanged

200 7.0 6.5 30 225 7.5 6.5 30 250 8.0 6.5 30

275 8.0 7.0 35 300 8.5 7.0 35 325 9.0 7.0 40 350 9.0 7.5 40 375 9.5 7.5 45

400 10.0 7.5 45 425 10.0 8.0 45 450 10.5 8.0 50 475 11.0 8.0 50 500 11.0 8.5 55

525 11.5 8.5 55 550 12.0 8.5 55 600 12.5 9.0 60 650 13.0 9.5 65 700 14.0 9.5 70

750 14.5 10.0 75 800 10.5 80 850 10.5 85 900 11.0 90 950 11.5 90

1000 11.5 95 1050 12.0 100 1100 12.5 105 1150 12.5 110 1200 13.0 110

SECTION 11 11 Tables of Scantlings

Appendices

APPENDIX A

Calculation of Shear Stresses

A.1 General

The shear stresses in the side shell, and longitudinal bulkhead plating for vessels having continuous longitudinal bulkheads, and in the side shell in way of wing tanks for vessels without continuous longitudinal bulkheads are to be calculated, as specified by 2.2.3a, by an acceptable method. In general, the shear stresses should he determined based on the shear flow in the transverse section. The shear stress is the shear flow divided by the plate thickness, at the location considered.

For calculating shear flows, a computer program similar to AB Si

SHEAR should he generally used. Information about AB SiSHE AR can he obtained from the Bureau's New York office.

When a computer program is not available, or at the early design stages, the following simplified method may be used to calculate shear stresses.

A.2 Shear Stress

The total shear stresses jr, in long tons per inch squared or metric tons per centimeter squared, in the side shell and longitudinal bulkhead plating may be determined by the following equation.

f, cKINFitH

c = 0.083 inch/pound units = 0.01 metric units

Ki -= 1 + y/811 distance, in ft or m, measured from the deck or bottom (depending on whether the strake considered is above or below the neutral axis of the section) to the point under consideration

= distance, in ft or m, measured from the deck (bottom) to the neutral axis of the section, when the strake under considera-tion is above (below) the neutral axis

N = shear distribution factor as given in Figure A.1 F = total shearing force, F. Fd , in long tons or metric tons, at

the section considered t = plate thickness, in in. or cm, at the location considered H = depth, in ft or rn, of the side shell or longitudinal bulkhead

plating considered, see Figure A.1

APPENDIX A 1

For vessels having structural configurations departing from those shown in Figure A.1, the calculation of shear stresses will be subject to special consideration.

1.3 Allowable Still-water Shearing Force

Alternatively, the allowable still-water shearing forces SWSF, in long tons or metric tons, at transverse sections of the hull-girder may be determined by the following equation.

SWSF 1 (NKO — Fa

C = 12 inch/pound units 100 metric units

f, the permissible shear stress, in long tons/in2 or metric tons/cm2, as specified in 2.2.3 dynamic shearing force, in long tons or metric tons, at the section considered as specified in 2.2.3b

fl = as defined in A.2 N

as defined in A.2 t = as defined in A.2

as defined in A.2

The allowable still-water shearing forces are to be determined for both the side shell and longitudinal bulkhead plating at various locations for each transverse section and the lowest value is to be used as the allowable still-water shearing lbrce at the section under consideration.

'PEND1X A 2

FIGURE A.1 Shear distribution configurations

Type 1

N,, = 0.5911,1D — 0.05 N,2 = 0.5 — — N5 Ne, = (0.21AblA,2 0.09)1ND A, 2 = total area, in in-ft or em-m, of side shell plating with the

region of H2

Type 2a

Ns = 0.5 — N5

N,, = NsH,ID N$2 = Ns N,,

= 0,16A5/A, C N51 = NaND N52 = N5 [(112ID + C21 C2 = 0 when h 0.15H2

= (0.611/H2 — 0.09) when Is > 0.15H2

Type 2b

C I = 0.115 for Type 2a = 0.08 for Type 2b

A = total area, in in-ft or cm-m, of the vertical projected longitudinal bulkhead plating

As = total projected area, in in-ft or cm-m, of the side shell plating for the full depth of the vessel

APPENDIX ,6,4

Top of deck line

Freeboard to be measured from

center of diamond to ton of deck line

1-4 15 in.--P-1 asEnsummummoas

3 in.

These measurements to be taken from

center of diamond to top of each line

26 in. forward of center of diamond

Upper edge of horizontal l'ne to

pass through center of diamond

thickness of all fines 1 in.

APPENDIX B

Load Line Markings

Inches

The American Bureau of Shipping is authorized to assign Load Lines to vessels navigating on the Great Lakes registered in the United States and Canada, Requests for the assignment of Load Lines are to he made an forms which wilt he furnished by one of the offices of the Bureau.

The Center of Diamond to be placed on both sides of vessel at the middle of the length on the load line. The diamond and lines are to he permanently marked by center punch marks or chisel, and the particulars given in the Load Line Certificate are to be entered in the official log.

The markings shown are for the starboard side; on the port side the markings are to he similar, and forward of diamond.

A B American Bureau of Shipping MS Midsummer Load Line S Summer Load Line I Load Line in Intermediate Seasons W Winter Load Line SW Salt Water FW Fresh Water

Note The salt water marks are assigned only to vessels intending to load in salt water of the St. Lawrence 'River.

APPENDIX 811

Top of deck line

Freeboard to be measured from

center of diamond to top of deck line

115 mz

Upper edge of horizontal line to

sass through center of diamond

380 11111)

EIMINNIMNIMINIMPOIPM

r1_675 mm forward of r center of diamond

75 mm

These measurements to be taken from

center of diamond to top of each line

380 mm

540 mm 38 mm

thickness of all lines 25 mm 230 mm 230 mm

Millimeters

The American Bureau of Shipping is authorized to assign Load Lines to vessels navigating on the Great Lakes registered in the United States and Canada. Requests for the assignment of Load Lines are to be made on forms which will he furnished by one of the offices of the Bureau.

The Center of Diamond to he placed on both sides of vessel at the middle of the length on the load line. The diamond and lines are to be permanently marked by center punch marks or chisel, and the particulars given in the Load Line Certificate are to he entered in the official log.

The markings shown are for the starboard side; on the port side the markings are to be similar, and forward of diamond.

A B American Bureau of Shipping MS Midsummer Load Line S Summer Load Line

Load Line in Intermediate Seasons W Winter Load Line SW Salt Water FW Fresh Water

Note The salt water marks are assigned only to vessels intending to load in salt water of the St. Lawrence River.

APPENDIX B

Documents

Rules for Building and Classing Bulk Carriers for Service ...ww2.eagle.org/content/dam/eagle/rules-and-guides/current/special... · Rules for Building and Classing Bulk Carriers for