Corrigenda 2 Rule Editorials

Transcription

1 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS Common Structural Rules for Bulk Carriers, January 006 Corrigenda Rule Editorials Notes: (1) These Rule Corrigenda enter into force on 1 April 006. () This document contains a copy of the affected rule along with the editorial change or clarification noted as applicable. Copyright in these Common Structural Rules for Bulk Carriers is owned by: American Bureau of Shipping Bureau Veritas China Classification Society Det Norske Veritas Germanischer Lloyd Korean Register of Shipping Lloyd's Register Nippon Kaiji Kyokai Registro Italiano Navale Russian Maritime Register of Shipping Copyright 006 The IACS members, their affiliates and subsidiaries and their respective officers, employees or agents are, individually and collectively, referred to in this clause as the IACS Members. The IACS Members, individually and collectively, assume no responsibility and shall not be liable to any person for any loss, damage or expense caused by reliance on the information or advice in this document or howsoever provided, unless that person has signed a contract with the relevant IACS Member entity for the provision of this information or advice and in that case any responsibility or liability is exclusively on the terms and conditions set out in that contract. PAGE 1 OF

2 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA CHAPTER STRUCTURAL DESIGN PRINCIPLES SECTION 6 STRUCTURAL ARRANGEMENT PRINCIPLES 7. Double side structure 7.1 Application The requirement of this article applies to longitudinally or transversely framed side structure. The transversely framed side structures are built with transverse frames possibly supported by horizontal side girders. The longitudinally framed side structures are built with longitudinal ordinary stiffeners supported by vertical primary supporting members. The side within the hopper and topside tanks is, in general, to be longitudinally framed. It may be transversely framed when this accepted for the double bottom and the deck according to and respectively. Editorial correction incorrect reference. 10. Bulkhead structure 10. Corrugated bulkheads General For ships of 190m of length L and above, the transverse vertically corrugated watertight bulkheads are to be fitted with a lower stool, and generally with an upper stool below the deck. For ships less than 190m in length L, In ships less than 150 m in length, corrugations may extend from the inner bottom to the deck provided the global strength of hull structures are satisfactorily proved for ships having ship length L of 150m and above by DSA as required by Ch 7 of the Rules. The correction is made to be in line with IACS UR S18. PAGE OF

3 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS Upper stool The upper stool, when fitted, is to have a height in general between two and three times the depth of corrugations. Rectangular stools are to have a height in general equal to twice the depth of corrugations, measured from the deck level and at the hatch side girder. The upper stool of transverse bulkhead is to be properly supported by deck girders or deep brackets between the adjacent hatch end beams. The width of the upper stool bottom plate is generally to be the same as that of the lower stool top plate. The stool bottom top of non-rectangular stools is to have a width not less than twice the depth of corrugations. The thickness and material of the stool bottom plate are to be the same as those of the bulkhead plating below. The thickness of the lower portion of stool side plating is to be not less than 80% of that required for the upper part of the bulkhead plating where the same material is used. The ends of stool side ordinary stiffeners when fitted in a vertical plane, are to be attached to brackets at the upper and lower end of the stool. The stool is to be fitted with diaphragms in line with and effectively attached to longitudinal deck girders extending to the hatch end coaming girders or transverse deck primary supporting members as the case may be, for effective support of the corrugated bulkhead. Scallops in the brackets and diaphragms in way of the connection to the stool bottom plate are to be avoided. Editorial correction PAGE OF

4 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA CHAPTER DESIGN LOADS SECTION HULL GIRDER LOADS 1. General 1.1 Sign conversions of bending moments and shear forces Absolute values are to be taken for bending moments and shear forces introduced in this Section. The sign of bending moments and shear forces is to be considered according to Sec, Tab. The sign conventions of vertical bending moments, horizontal bending moments and shear forces at any ship transverse section are as shown in Fig 1, namely: the vertical bending moments M SW and M WV are positive when they induce tensile stresses in the strength deck (hogging bending moment) and are negative in the opposite case (sagging bending moment) the horizontal bending moment M WH is positive when it induces tensile stresses in the starboard and is negative in the opposite case. the vertical shear forces Q Q SW, Q WV is are positive in the case of downward resulting forces preceding and upward resulting forces following the ship transverse section under consideration, and is negative in the opposite case. Q (+) Q SW, Q WV (+) Q SW, Q WV Aft Fore Aft Fore M SW, M WV (+) M SW, M WV (+) Aft Fore Aft Fore M WH (+) M WH (+) Figure 1: Sign conventions for shear forces Q Q SW, Q WV and bending moments M SW, M WV and M WH Editorial correction PAGE OF

5 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS CHAPTER 5 HULL GIRDER STRENGTH SECTION 1 YIELDING CHECK. Hull girder stresses. Shear stresses.. Simplified calculation of shear stresses induced by vertical shear force The shear stresses induced by the vertical shear forces in the calculation point are obtained, in N/mm, from the following formula:. Q C Full hold Empty hold Q C = pαt 1 Corrected shear force Shear force obtained as specified in Ch, Sec Q C Full hold Empty hold Corrected shear force Q C = ραt LC Shear force obtained as specified in Ch, Sec Figure : Shear force correction Q C Editorial correction correction of equation in Figure PAGE 5 OF

6 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA. Section modulus and moment of inertia. Midship section moment of inertia..1 The net midship section moment of inertia about its horizontal neutral axis is to be not less than the value obtained, in m, from the following formula: I YR ' R, MIN = Z L 10 where Z R,MIN is the required net midship section modulus Z R,MIN, in m, calculated as specified in [..1] or [..], but assuming k = 1. The correction is made to be in line with IACS UR. PAGE 6 OF

7 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS CHAPTER 5 HULL GIRDER STRENGTH APPENDIX 1 HULL GIRDER ULTIMATE STRENGTH. Criteria for the calculation of the curve M-χ. Load-end shortening curves σ-ε.. Beam column buckling The equation describing the load-end shortening curve σ CR1 -ε for the beam column buckling of ordinary stiffeners composing the hull girder transverse section is to be obtained from the following formula (see Fig ): σ CR1 where: = Φσ C1 A A Stif Stif + 10b E t + 10st p p Φ : Edge function defined in [..] A Stif : Net sectional area of the stiffener, in cm, without attached plating σ C1 : Critical stress, in N/mm, equal to: σ E C 1 = ε for σ ReH E1 ε σ 1 Φ R = eh ε ReH σ C1 ReH 1 for σ E1 > ε σ E 1 ε : Relative strain defined in [..] σ E1 : Euler column buckling stress, in N/mm, equal to: I E b E1 σ E 1 = 10 E π E AEl I : Net moment of inertia of ordinary stiffeners, in cm, with attached shell plating of width b E1 : Effective width, in m, of the attached shell plating, equal to: s be1 = for β E >1. 0 β E b E 1 = s for β E 1. 0 β E = 10 s t p εr E eh A E b E : Net sectional area, in cm, of ordinary stiffeners with attached shell plating of width b E : Effective width, in m, of the attached shell plating, equal to: b E s β E β E = for β >1. 5 E PAGE 7 OF

8 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA b E = s for β 1. 5 E Figure Load-end shortening curve σ CR1 -ε for beam column buckling Editorial correction of formula...5 Torsional Buckling The equation describing the load-end shortening curve σ CR -ε for the flexural-torsional buckling of ordinary stiffeners composing the hull girder transverse section is to be obtained according to the following formula (see Fig ). σ CR where: A = Φ Stif σ A C Stif + 10st pσ + 10st Φ : Edge function defined in [..] p CP A Stif : Net sectional area of the stiffener, in cm, without attached plating σ C : Critical stress, in N/mm, equal to: σ E C = ε for σ ReH E ε σ Φ R = eh ε ReH σ C ReH 1 for σ E > ε σ E σ E : Euler torsional buckling stress, in N/mm, defined in Ch 6, Sec, [.] ε : Relative strain defined in [..] σ CP : Buckling stress of the attached plating, in N/mm, equal to: σ R CP = β E β E eh for β >1. 5 σ CP = R eh for β E 1. 5 β E : Coefficient defined in [..] E PAGE 8 OF

9 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS Figure Load-end shortening curve σ CR -ε for flexural-torsional buckling Editorial correction of formula...7 Web local buckling of ordinary stiffeners made of flat bars The equation describing the load-end shortening curve σ CR -ε for the web local buckling of flat bar ordinary stiffeners composing the hull girder transverse section is to be obtained from the following formula (see Fig 5): σ CR where: = Φ st σ + A σ A + 10st 10 P CP Stif C Stif Φ : Edge function defined in [..] P A Stif : Net sectional area of the stiffener, in cm, without attached plating σ CP : Buckling stress of the attached plating, in N/mm, defined in [..5] σ C : Critical stress, in N/mm, equal to: σ E C = ε for σ ReH E ε σ Φ R = eh ε ReH σ C ReH 1 for σ E > ε σ E σ E : Local Euler buckling stress, in N/mm, equal to: t σ = E h ε : Relative strain defined in [..]. w w PAGE 9 OF

10 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA Figure 5 Load-end shortening curve σ CR -ε for web local buckling Editorial correction of formula. PAGE 10 OF

11 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS CHAPTER 6 HULL SCANTLINGS SECTION 1 PLATING. General requirements.5 Sheerstrake.5.1 Welded sheerstrake The net thickness of a welded sheerstrake is to be not less than the actual net thicknesses of the adjacent m width side plating, taking into account higher strength steel corrections if needed. Editorial correction SECTION ORDINARY STIFFENERS. Yielding check. Strength criteria for single span ordinary stiffeners other than side frames of single side bulk carriers.. Supplementary strength requirements In addition to [..1], the net moment of inertia, in cm, of the side frames located immediately abaft the collision bulkhead is to be not less than the value obtained from the following formula: ( p + p ) S W l Ι = 018. n where: l : Side frame span, in m n : Number of frames from the bulkhead to the frame in question, taken equal to 1, or s : Frame spacing, in m As an alternative, supporting structures, such as horizontal stringers, are to be fitted between the collision bulkhead and a side frame which is in line with transverse webs fitted in both the topside tank and hopper tank, maintaining the continuity of forepeak stringers within the foremost hold. Editorial correction definition of frame spacing is deleted. PAGE 11 OF

12 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA. Upper and lower connections of side frames of single side bulk carriers.. The net connection area, A i, in cm, of the bracket to the i-th longitudinal stiffener supporting the bracket is to be obtained from the following formula: w s k Ai = 0 k where: i. l 1 bkt lg, i w i : Net section modulus, in cm, of the i-th longitudinal stiffener of the side or sloped bulkheads that support the lower or the upper end connecting bracket of the side frame, as applicable l 1 : As defined in [..1] k bkt : Material factor for the bracket k lg,i : Material factor for the i-th longitudinal stiffener s : Frame spacing, in m Editorial correction PAGE 1 OF

13 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS. Web stiffeners of primary supporting members.1 Net scantlings.1. Connection ends of web stiffeners The stress at ends of web stiffeners of primary supporting members in water ballast tanks, in N/mm, is to comply with the following formula when no bracket is fitted:. b s b s b s b' b' Standard shapes of the end of the stiffener b' Shape of the end of the stiffener considering fatigue strength in comparison with the standard shape b s b s b s b' b' b' Standard shapes of the end of the stiffener Shape of the end of the stiffener considering fatigue strength in comparison with the standard shape Figure 9 : Shape of the end of the web stiffener Editorial correction correction of the indication of the smallest breadth (b') shown in the lefthand figure PAGE 1 OF

14 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA SECTION BUCKLING & ULTIMATE STRENGTH OF ORDINARY STIFFENERS AND STIFFENED PANELS 1. General The buckling checks have to be performed for the following elements: a) according to requirements of [], [] and [] and for all load cases as defined in Ch, Sec in intact condition: Elementary plate panels and ordinary stiffeners in a hull transverse section analysis, Elementary plate panels modeled in FEM as requested in Ch 7. b) according to requirements of [6] and only in flooded condition: transverse vertically corrugated watertight bulkheads for BC-A and BC-B ships. Editorial correction. Buckling criteria of partial and total panels. Ultimate strength in lateral buckling mode.. Evaluation of the bending stress σ b The bending stress σ b, in N/mm, in the stiffeners is equal to: M 0 + M σ b = W 10 with: M 0 st 1 : Bending moment, in N.mm, due to the deformation w of stiffener, taken equal to: M 0 = F Ki pzw c p with ( c p ) > 0 f f z z M 1 : Bending moment, in N.mm, due to the lateral load p, taken equal to: M 1 = pba for longitudinal stiffeners 10 PAGE 1 OF

15 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS ( n b) pa M1 = for transverse stiffeners, with n equal to 1 for ordinary 8c S 10 transverse stiffeners. W st : Net section modulus of stiffener (longitudinal or transverse), in cm, including effective width of plating according to 5, taken equal to: c S p F Ki if a lateral pressure is applied on the stiffener: W st is the net section modulus calculated at flange if the lateral pressure is applied on the same side as the stiffener. W st is the net section modulus calculated at attached plate if the lateral pressure is applied on the side opposite to the stiffener. if no lateral pressure is applied on the stiffener: W st is the minimum net section modulus among those calculated at flange and attached plate : Factor accounting for the boundary conditions of the transverse stiffener c S = 1.0 for simply supported stiffeners c S =.0 for partially constraint stiffeners : Lateral load in kn/m, as defined in Ch, Sec5 and Ch, Sec 6 calculated at the load point as defined in Ch 6, Sec, [1..1.] : Ideal buckling force, in N, of the stiffener, taken equal to: π FKix = EI x 10 for longitudinal stiffeners a π ( nb) FKiy = EI y 10 for transverse stiffeners I x, I y : Net moments of inertia, in cm, of the longitudinal or transverse stiffener including effective width of attached plating according to 5. I x and I y are to comply with the following criteria: bt I x 1 10 at I y 1 10 p z : Nominal lateral load, in N/mm, of the stiffener due to σ x, σ y and τ t a π b p + + zx = σ xl c yσ y τ1 for longitudinal stiffeners b a t a π a Ay p + zy = c xσ xl + σ y 1 + τ1 for transverse stiffeners a nb ata σ t a xl A σ x 1 + bt = x a : Net thickness offered of attached plate, in mm PAGE 15 OF

16 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA c x, c y : Factor taking into account the stresses vertical to the stiffener's axis and distributed variable along the stiffener's length taken equal to: 0. 5( 1+ ψ ) for 0 ψ ψ for ψ < 0 A x, A y : Net sectional area, in mm, of the longitudinal or transverse stiffener respectively without attached plating m1 m τ 1 = τ t ReHE + 0 a b m 1, m : Coefficients taken equal to: w = w 0 + w 1 for longitudinal stiffeners: for transverse stiffeners: a. 0 : b a <. 0 : b a 0. 5 n b a < 0. 5 n b m m : : 1 1 = 1. 7 = m m 1 1 m m = 0. 7 = 0. 9 = 0. 9 = 0. 7 m m = n 1. 7 = n w 0 w 1 : Assumed imperfection, in mm, taken equal to: a b w 0 = min(,, 10) for longitudinal stiffeners a n b w0 = min(,, 10) for transverse stiffeners For stiffeners sniped at both ends w 0 must not be taken less than the distance from the midpoint of attached plating to the neutral axis of the stiffener calculated with the effective width of its attached plating. : Deformation of stiffener, in mm, at midpoint of stiffener span due to lateral load p. In case of uniformly distributed load the following values for w 1 may be used: pba = for longitudinal stiffeners 8 10 EI x w1 7 5ap( nb) w1 = EI y c S for transverse stiffeners c f : Elastic support provided by the stiffener, in N/mm, taken equal to: for longitudinal stiffeners ( c px π c f = FKix 1 + a ) PAGE 16 OF

17 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS c px 1 = 1 10 I t b 1+ c xa x 1 c xa : Coefficient taken equal to : a b c xa = + b a for a b a c xa = 1 + for a < b b for transverse. stiffeners : f S Kiy π ( c ) py ( n b) c = c F 1 + c py 1 = 1 10 I t a 1+ c ya y 1 c ya : Coefficient taken equal to : nb a c ya = + a nb for nb a nb c ya = 1 + for nb < a a Editorial correction error in reference.. Equivalent criteria for longitudinal and transverse ordinary stiffeners not subjected to lateral pressure Longitudinal and transverse ordinary stiffeners not subjected to lateral pressure are considered as complying with the requirement of [..1] if their net moments of inertia I x and I y, in cm, are not less than the value obtained by the following formula: For longitudinal stiffener : I p zxa w 0xhw a = + π 10 ReH σ π E x S x I p zxa w 0hw a = + π 10 ReH σ π E x S x PAGE 17 OF

18 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA For transverse stiffener : I p zy( nb) w h 0y w ( nb) = + π 10 ReH σ π E y S y I p zy( nb) w 0hw ( nb) = + π 10 ReH σ π E y S y Editorial correction of symbols in formulae. w 0y and w 0z corrected to w 0.. Torsional buckling..1 Longitudinal stiffeners The longitudinal ordinary stiffeners are to comply with the following criteria: σ xs κ R T κ T λ T eh 1.0 : Coefficient taken equal to: κ = 1.0 for λ 0. T T 1 κt = for λ T > 0. Φ + Φ λ T ( ( λ 0 ) + λ ) Φ = T. T : Reference degree of slenderness taken equal to: λ = T R σ eh KiT I P E π I ω 10 σ = KiT ε I T I, in N/mm P a : Net polar moment of inertia of the stiffener, in cm, defined in Tab 5, and related to the point C as shown in Fig I T : Net St. Venant's moment of inertia of the stiffener, in cm, defined in Tab 5, I ω : Net sectorial moment of inertia of the stiffener, in cm 6, defined in Tab 5, related to the point C as shown in Fig ε : Degree of fixation taken equal to: ε = π I b t w a h + w t A w : Net web area equal to: A w = hwtw f w A : Net flange area equal to: A = b f t f f PAGE 18 OF

19 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS t f e f = hw +, in mm b f b f b f t w t w t w t w tf hw ef b 1 b 1 b C C C C ta e f = hw + t f / Figure : Dimensions of stiffeners Table 5: Moments of inertia Profile I P I T I w Flat bar h w t w 10 Sections with bulb or flange A wh w + A f e f 10 h wtw 10 h wtw 10 b f t f 10 t h w. h w t w 6 w 6 10 t w hw + t f b f for bulb and angle sections: A f e f b f A f +. 6Aw A f + Aw for tee-sections f t f b e 1 10 f 6 Editorial correction delete the definition in the figure. 6. Transverse vertical corrugated watertight bulkhead in flooded conditions for BC-A and BC-B ships Editorial correction PAGE 19 OF

20 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA SECTION PRIMARY SUPPORTING MEMBERS. Additional requirements for primary supporting members of BC-A and BC-B ships.1 Evaluation of double bottom capacity and allowable hold loading in flooded conditions.1. Allowable hold loading The allowable hold loading is to be obtained, in t, from the following formula: 1 W = ρ C V F where: F : Coefficient to be taken equal to: F = 1.1 in general F = 1.05 for steel mill products V : Volume, in m, occupied by cargo at a level h B h B X D 1 h f : Level of cargo, in m, to be obtained from the following formula: X hb = ρ g C : Pressure, in kn/m, to be obtained from the following formulae: for dry bulk cargoes, the lesser of: Z + ρ g( zf 0. 1D 1 hf ) X = ρ 1+ ( perm 1) ρc X Z + ρ g z 0.1D h perm ( ) = F 1 for steel mill products: Z + ρg z 0. 1D 1 X = ρ 1 ρ F ( ) F h F C : Distance, in m, from the base line to the freeboard deck at side amidships : Inner bottom flooding head is the distance, in m, measured vertically with the ship in the upright position, from the inner bottom to a level located at a distance z F, in m, from the baseline. z F : Flooding level, in m, defined in Ch, Sec 6, [....] perm : Permeability of cargo, which need not be taken greater than 0. Z : Pressure, in kn/m, to be taken as the lesser of: C H Z = A C Z = A DB, H E DB, E PAGE 0 OF

21 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS C H C E : Shear capacity of the double bottom, in kn, to be calculated according to [.1.1], considering, for each floor, the lesser of the shear strengths S f1 and S f (see [.1.]) and, for each girder, the lesser of the shear strengths S g1 and S g (see [.1.]) : Shear capacity of the double bottom, in kn, to be calculated according to [.1.1], considering, for each floor, the shear strength S f1 (see [.1.]) and, for each girder, the lesser of the shear strengths S g1 and S g (see [.1.]) n S i ADB, H = SiB n i= 1 DB, i A = S ( B s) DB, E n i= 1 i DB : Number of floors between stools (or transverse bulkheads, if no stool is fitted) : Space of i-th floor, in m B DB,i : Length, in m, to be taken equal to : B DB,i = B DB - s for floors for which S f1 < S f (see [.1.]) B DB,i = B DB,h for floors for which S f 1 S f (see [.1.]) B DB : Breadth, in m, of double bottom between the hopper tanks (see Fig ) B DB,h : Distance, in m, between the two openings considered (see Fig ) s : Spacing, in m, of inner bottom longitudinal ordinary stiffeners adjacent to the hopper tanks. Editorial correction error in reference PAGE 1 OF

22 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA CHAPTER 7 DIRECT STRENGTH ANALYSIS SECTION GLOBAL STRENGTH EF ANALYSIS OF CARGO HOLE STRUCTURES. Analysis model.5 Consideration of hull girder loads.5. Influence of local loads The distribution of hull girder shear force and bending moment induced by local loads applied on the model are calculated using a simple beam theory for the hull girder. Reaction forces at both ends of the model and distributions of shearing forces and bending moments induced by local loads can be determined by following formulae: r r ( xi xaft ) fi z r i RV _ fore = R V _ aft = f i z r + RV _ fore x fore xaft i r r ( xi xaft ) f i y r i RH _ fore = R H _ aft = fi y r + RH _ fore x fore xaft i r r QV _ FEM ( x) = RV _ aft f i z when x i < x i r r QH _ FEM ( x) = RH _ aft + fi y when x i < x i r r MV _ FEM ( x) = ( x xaft ) RV _ aft ( x xi ) f i z when x i < x i r r MH _ FEM ( x) = ( x xaft ) RH _ aft + ( x xi ) fi y when x i < x where: x aft : Location of the aft end support x fore : Location of the fore end support x R V _ aft, V fore : Considered location i R _, R H _ aft and R H _ fore : Vertical and horizontal reaction forces at the fore and aft ends Q V _ FEM, H FEM r f i Q _, M V _ FEM and M H _ FEM : Vertical and horizontal shear forces and bending moments created by the local loads applied on the FE model. Sign of Q V_FEM, M V_FEM and M H_FEM is in accordance with the sign convention defined in Ch, Sec. The sign convention for reaction forces is that a positive creates a positive shear force. : Applied force on node i due to all local loads PAGE OF

23 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS x i : Longitudinal coordinate of node i Clarification of sign convention.5.6 Direct method In direct method the effect of hull girder loads are directly considered in D FE model. The equilibrium loads are to be applied at both model ends in order to consider the hull girder loads as specified in [.5.] and [.5.] and influence of local loads as specified in [.5.]. In order to control the shear force at the target locations, two sets of enforced moments are applied at both ends of the model. These moments are calculated by following formulae: M M Y _ aft _ SF Z _ aft _ SF = M = M Y _ fore _ SF Z _ fore _ SF ( x = ( x = fore fore x x aft aft ) ) [ Q ( x ) Q ( x )] V _ T eq V _ FEM [ Q ( x ) Q ( x )] H _ T eq H _ FEM In order to control the bending moments at the target locations, another two sets of enforced moments are applied at both ends of the model. These moments are calculated by following formulae: M M x eq xaft = M Y _ fore _ BM = MV _ T ( xeq ) MV _ FEM ( xeq MY _ aft _ SF 1 x fore xaft Y _ aft _ BM ) x eq xaft = M Z _ fore _ BM = MH _ T ( xeq ) MH _ FEM ( xeq MZ _ aft _ SF 1 x fore xaft Z _ aft _ BM ) where: x eq : Considered location for the hull girder loads evaluation, Q V _ FEM, H FEM Q V _ T, H T M Y M Z Q _, M V _ FEM, M H _ FEM : As defined in [.5.] Q _, M V _ T, M H _ T : Target vertical and horizontal shear forces and bending moments, defined in Tab or Tab, at the location x eq. Sign of Q V_T, M V_T and M H_T is in accordance with sign convention defined in Ch, Sec. M M _ aft _ SF, Y _ fore _ SF, Y _ aft _ BM, Y fore _ BM M eq eq _ : Enforced moments to apply at the aft and fore ends for vertical shear force and bending moment control, positive for clockwise around y-axis. The sign convention for M Y_aft_SF, M Y_fore_SF, M Y_aft_BM and M Y_fore_BM is that of the FE model axis. The sign convention for other bending moment, shear forces and reaction forces is in accordance with the sign convention defined in Ch, Sec. M M _ aft _ SF, Z _ fore _ SF, Z _ aft _ BM, Z fore _ BM M _ : Enforced moments to apply at the aft and fore ends for horizontal shear force and bending moment control, positive for clockwise around z-axis. The sign convention for M Z_aft_SF, PAGE OF

24 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA M Z_fore_SF, M Z_aft_BM and M Z_fore_BM is that of the FE model axis. The sign convention for other bending moment, shear forces and reaction forces is in accordance with the sign convention defined in Ch, Sec. The enforced moments at the model ends can be generated by one of the following methods: to apply distributed forces at the end section of the model, with a resulting force equal to zero and a resulting moment equal to the enforced moment. The distributed forces are applied to the nodes on the longitudinal members where boundary conditions are given according to Tab 1. The distributed forces are to be determined by using the thin wall beam theory to apply concentrated moments at the independent points defined in [..1]. Clarification of sign conventions PAGE OF

25 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS CHAPTER 8 FATIGUE CHECK OF STRUCTURAL DETAILS SECTION FATIGUE STRENGTH ASSESSMENT. Calculation of fatigue damage. Long-term distribution of stress range..1 The cumulative probability density function of the long-term distribution of combined notch stress ranges is to be taken as a two-parameter Weibull distribution: F( x) F( x) where: x exp σ ξ 1 = 1 ( ln N ) ξ R W, j x 1 exp σ E ( ln N ) = R, j ξ ξ : Weibull shape parameter, taken equal to 1.0 N R : Number of cycles, taken equal to 10. Editorial correction - correction of error in formula PAGE 5 OF

26 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA SECTION STRESS ASSESSMENT OF STIFFENERS. Hot spot mean stress. Mean stress according to the superimposition method.. The hot spot stress due to still water bending moment, in N/mm, in loading condition (k) is to be obtained with the following formula: MS, ( k) ( z N) σ = 10 GS, ( k) K gh I where: Y M S, (k) : Still water vertical bending moment, in kn.m, defined in Sec, [..1..]. Editorial correction error in reference. PAGE 6 OF

27 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS APPENDIX1 CROSS SECTIONAL PROPERTIES FOR TORSION 1. Calculation formulae 1. Computation of cross sectional properties for the entire cross section Asymmetric cross section: A = A A = A y s = z s = I y = I z = S z A S y A I y A z s y I z A y s z I yz = I yz A y s zs s t I T = ω 0 = S ω I ω y = ωy A y s ω0 I ω z = I ωz A zs ω0 I ω z I z I ω y I yz y M = I I I z M = I ω z I A I y y I y z z yz yz I ω y I I I ω = Iω Aω + zm Iωy y M Iωz yz I y 0 ω Symmetric cross section (only half of the section is modeled) S y z s = A I = ( I A z ) I z A y I z A y y s I = ( ) s ( ) s I T = + ( A yi Φ i ) s t I ω = I ω y z I M = ω y I z Cell i I = I ω + z m I ωy Editorial correction correction of error in formula PAGE 7 OF

28 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA CHAPTER 9 OTHER STRUCTURES SECTION 1 FORE PART. Load model. Pressure in bow area.. Lateral pressure in testing conditions The lateral pressure p T in testing conditions is defined in Ch, Sec 6, [] taken equal to: p T = p ST p S for bottom shell plating and side shell plating p T = p ST otherwise where: p ST : Testing pressure defined in Ch, Sec 6, [] p S : Pressure taken equal to: if the testing is carried out afloat: hydrostatic pressure defined in Ch, Sec 5, [1] for the draught T 1, defined by the Designer, at which the testing is carried out. If T 1 is not defined, the testing is considered as being not carried out afloat. if the testing is not carried out afloat: p S = 0 Editorial correction this correction is made to be consistent with Ch 6, Sec 1, [.1.] and Ch 6, Sec, [.1.] PAGE 8 OF

29 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS SECTION AFT PART. Load model. Lateral pressures.. Lateral pressure in testing conditions The lateral pressure p T in testing conditions is defined in Ch, Sec 6, [] taken equal to: p T = p ST p S for bottom shell plating and side shell plating p T = p ST otherwise where: p ST : Testing pressure defined in Ch, Sec 6, [] p S : Pressure taken equal to: if the testing is carried out afloat: hydrostatic pressure defined in Ch, Sec 5, [1] for the draught T 1, defined by the Designer, at which the testing is carried out. If T 1 is not defined, the testing is considered as being not carried out afloat. if the testing is not carried out afloat: p S = 0 Editorial correction this correction is made to be consistent with Ch 6, Sec 1, [.1.] and Ch 6, Sec, [.1.] PAGE 9 OF

30 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA SECTION MACHINERY SPACE 7. Main machinery seating 7. Minimum scantlings 7..1 The net scantlings of the structural elements in way of the internal combustion engine seatings are to be obtained from the formulae in Tab. Table 1: Minimum scantlings of the structural elements in way of machinery seatings Scantling minimum value Net cross-sectional area, in cm, of each bedplate of the seatings Bedplate net thickness, in m mm P n r L E Scantling minimum value Bedplates supported by two or more girders: P n r L E Bedplates supported by one girder: Total web net thickness, in mm, of girders fitted in way of machinery seatings P n r L E Bedplates supported by two or more girders: P n r L E Bedplates supported by one girder: P n r L E Web net thickness, in mm, of floors fitted in way of machinery seatings P n r L E Editorial correction correction of unit PAGE 0 OF

31 CORRIGENDA COMMON STRUCTURAL RULES FOR BULK CARRIERS SECTION 5 HATCH COVERS. Load model.1 Lateral pressures and forces.1. Sea pressure The still water and wave lateral pressures are to be considered and are to be taken equal to: still water pressure: p = 0 S wave pressure p W, as defined in Ch, Sec 5 [.5.]. Editorial correction error in reference 5. Strength check 5. Plating 5.. Minimum net thickness Ref. ILLC, as amended (Resolution MSC.1(77) Reg. 16 (5, c)) In addition to [5..1], the net thickness, in mm, of the plating forming the top of the hatch cover is to be not less than the greater of the following values: t = 0. 01s t = 10s t = 6 Editorial correction correction of error in formula PAGE 1 OF

32 COMMON STRUCTURAL RULES FOR BULK CARRIERS CORRIGENDA CHAPTER 10 HULL OUTFITTING SECTION 1 RUDDER AND MANOEUVRING ARRANGEMENT. Rudder couplings.5 Cone couplings with special arrangements for mounting and dismounting the couplings.5.1 Where the stock diameter exceeds 00 mm, the press fit is recommended to be effected by a hydraulic pressure connection. In such cases the cone is to be more slender, c 1: c 1: 1 to 1: 0. Editorial correction correction of error in formula PAGE OF