RULES FOR CLASSIFICATION OF SHIPS NEWBUILDINGS HULL AND EQUIPMENT MAIN CLASS PART 3 CHAPTER 1 HULL STRUCTURAL DESIGN SHIPS WITH LENGTH 100 METRES AND ABOVE JANUARY 2009 CONTENTS Sec. 1 General Requirements................................................................................................................7 Sec. 2 Materials...................................................................................................................................11 Sec. 3 Design Principles......................................................................................................................16 Sec. 4 Design Loads............................................................................................................................32 Sec. 5 Longitudinal Strength...............................................................................................................40 Sec. 6 Bottom Structures.....................................................................................................................52 Sec. 7 Side Structures..........................................................................................................................60 Sec. 8 Deck Structures........................................................................................................................70 Sec. 9 Bulkhead Structures .................................................................................................................76 Sec.10 Superstructure Ends, Deckhouse Sides and Ends, Bulwarks...................................................82 Sec.11 Welding and Weld Connections...............................................................................................85 Sec.12 Direct Strength Calculations ...................................................................................................90 Sec.13 Buckling Control......................................................................................................................95 Sec.14 Structures for High Temperature Cargo.................................................................................101 Sec.15 Special Requirements - Additional Class...............................................................................104 Sec.16 Fatigue Control ......................................................................................................................111 App.A Elastic Buckling and Ultimate Strength.................................................................................112 DET NORSKE VERITAS Veritasveien 1, NO-1322 Høvik, Norway Tel.: +47 67 57 99 00 Fax: +47 67 57 99 11 CHANGES IN THE RULES General been updated — H201: The last paragraph has been removed, while stern slam- The present edition of the rules includes additions and amendments ming requirements have been moved to Sec.7 E200, modified to decided by the Board as of December 2008, and supersedes the Janu- require that the stern always to be checked with respect to the re- ary 2008 edition of the same chapter, including later amendments. quirements in H213 and H214. The rule changes come into force as indicated below. — H203: The definition of design forward draught for bottom slam- ming calculations has been modified. This chapter is valid until superseded by a revised chapter. Supple- — H207: Effective load length for bottom slamming loads has been ments will not be issued except for an updated list of minor amend- corrected from (l - s) to (l - 0.5s). ments and corrections presented in Pt.0 Ch.1 Sec.3. Pt.0 Ch.1 is — H208: The connection area formula has been clarified. normally revised in January and July each year. — H210: A new paragraph has been introduced to address slam- Revised chapters will be forwarded to all subscribers to the rules. ming evaluation of primary members. Buyers of reprints are advised to check the updated list of rule chap- — H211: Introduce new requirements for stern slamming, and ap- ters printed in Pt.0 Ch.1 Sec.1 to ensure that the chapter is current. plication has been specified in H201. • Sec.7 Side Structures — C302: Same change as Sec.6 C603 (see above). Main changes coming into force 1 July 2009 — E106: Bow impact area has been extended aft for vessel with sig- nificant bow flare aft of 0.15 L. • Sec.2 Materials — E110: Shear area formula has been corrected. — The material requirements have been amended in line with UR — E111: Application of buckling requirement has been clarified. S6 rev.5, and the changes are mainly related to selection of ma- — E200: Requirements for stern slamming has been introduced. terial grade for outer shell. • Sec.8 Deck Structures - B204 has been clarified: as-built thickness shall be used as reference for material selection. — A406: The requirement for tapering has been modified. - New Tables B2 to B6 have been inserted. — C303: Same change as Sec.6 C603 (see above). In addition, the required minimum thickness for accommodation decks has been • Sec.3 Design Principles clarified as a fixed value 5.0 mm, not dependent on vessel length. — A400: The required position of collision bulkhead for passenger vessels has become the same as for cargo vessels. • Sec.9 Bulkhead Structures — A901: Minimum bow height requirements have been updated. — C202: Same change as Sec.6 C603 (see above). • Sec.4 Design Loads — B401: New default GM values have been defined for container Significant editorial changes taking effect immediately carriers. — B602: The application of combined vertical acceleration has • Sec.1 General Requirements been clarified. — In item D201 the documentation requirements for the BIS nota- • Sec.5 Longitudinal Strength tion have been clarified. — E203: Previous E203 has been found to deviate from the require- • Sec.7 Side Structures ment in IACS CSR and UR S5 and has been deleted. — In Table B1 the formula for p has been corrected. 5 • Sec.6 Bottom Structures — A501 and A503: The requirement for double bottom arrange- ments have been updated. Corrections and Clarifications — C603, C703, and C802: The minimum thickness requirements for stiffener webs, including minimum aspect ratio for flanged In addition to the above stated rule requirements, a number of correc- profiles, have been modified. tions and clarifications have been made to the existing rule text. — D101: The requirement for double bottom arrangements has Comments to the rules may be sent by e-mail to [email protected] For subscription orders or information about subscription terms, please use [email protected] Comprehensive information about DNV and the Society's services is found at the Web site http://www.dnv.com © Det Norske Veritas Computer Typesetting (Adobe FrameMaker) by Det Norske Veritas Printed in Norway If any person suffers loss or damage which is proved to have been caused by any negligent act or omission of Det Norske Veritas, then Det Norske Veritas shall pay compensation to such person for his proved direct loss or damage. However, the compensation shall not exceed an amount equal to ten times the fee charged for the service in question, provided that the maximum compen- sation shall never exceed USD 2 million. In this provision "Det Norske Veritas" shall mean the Foundation Det Norske Veritas as well as all its subsidiaries, directors, officers, employees, agents and any other acting on behalf of Det Norske Veritas. Rules for Ships, January 2009 Pt.3 Ch.1 Contents – Page 3 CONTENTS SEC. 1 GENERAL REQUIREMENTS.......................... 7 C. Local Design........................................................................21 C 100 Definition of span for stiffeners and girders...................21 A. Classification..........................................................................7 C 200 End connections of stiffeners..........................................22 A 100 Application........................................................................7 C 300 End connections of girders..............................................24 A 200 Class notations..................................................................7 C 400 Effective flange of girders..............................................25 C 500 Effective web of girders..................................................26 B. Definitions..............................................................................7 C 600 Stiffening of girders........................................................27 B 100 Symbols.............................................................................7 C 700 Reinforcement at knuckles..............................................28 B 200 Terms................................................................................7 C 800 Continuity of local strength members.............................29 B 300 Ship types..........................................................................9 C 900 Welding of outfitting details to hull................................29 C 1000 Properties and selection of sections................................29 C. Documentation......................................................................9 C 1100 Cold formed plating........................................................31 C 100 Plans and particulars.........................................................9 C 200 Specifications and calculations.......................................10 SEC. 4 DESIGN LOADS............................................... 32 C 300 Specific purpose documentation.....................................10 A. General................................................................................32 D. Ships Built for In-Water Survey of the Ship's A 100 Introduction.....................................................................32 Bottom and Related Items..................................................10 A 200 Definitions.......................................................................32 D 100 General............................................................................10 D 200 Documentation................................................................10 B. Ship Motions and Accelerations.......................................32 D 300 Markings of ship’s sides and bottom..............................10 B 100 General............................................................................32 D 400 Rudder.............................................................................10 B 200 Basic parameters.............................................................32 D 500 Tailshaft..........................................................................10 B 300 Surge, sway /yaw and heave accelerations.....................33 D 600 Thrusters.........................................................................10 B 400 Roll motion and acceleration..........................................33 B 500 Pitch motion and acceleration.........................................33 SEC. 2 MATERIALS...................................................... 11 B 600 Combined vertical acceleration.......................................34 B 700 Combined transverse acceleration..................................34 A. General.................................................................................11 B 800 Combined longitudinal accelerations..............................34 A 100 Introduction.....................................................................11 A 200 Material certificates.........................................................11 C. Pressures and Forces..........................................................34 C 100 General............................................................................34 B. Hull Structure Steel............................................................11 C 200 Sea pressures...................................................................34 B 100 General............................................................................11 C 300 Liquids in tanks...............................................................35 B 200 Material designations and classes...................................11 C 400 Dry cargoes, stores, equipment and accommodation......38 B 300 Basic requirements..........................................................11 B 400 Requirements for low air temperatures...........................13 C 500 Deck cargo units. Deck equipment.................................39 B 500 Material at cross-joints....................................................13 SEC. 5 LONGITUDINAL STRENGTH....................... 40 C. Alternative Structural Materials.......................................13 A. General................................................................................40 C 100 Aluminium......................................................................13 C 200 Stainless steel..................................................................13 A 100 Introduction.....................................................................40 A 200 Definitions.......................................................................40 D. Corrosion Additions for Steel Ships..................................14 D 100 General............................................................................14 B. Still Water and Wave Induced Hull Girder Bending D 200 Corrosion additions.........................................................14 Moments and Shear Forces...............................................40 D 300 Class notation ICM (Increased Corrosion Margin).........14 B 100 Stillwater conditions.......................................................40 B 200 Wave load conditions......................................................42 SEC. 3 DESIGN PRINCIPLES..................................... 16 C. Bending Strength and Stiffness.........................................44 A. Subdivision and Arrangement...........................................16 C 100 Midship section particulars.............................................44 A 100 General............................................................................16 C 200 Extent of high strength steel (HS-steel)..........................44 A 200 Definitions.......................................................................16 C 300 Section modulus .............................................................45 A 300 Number of transverse watertight bulkheads....................16 C 400 Moment of inertia...........................................................46 A 400 Position of collision bulkhead.........................................16 A 500 Height of watertight bulkheads.......................................17 D. Shear Strength....................................................................46 A 600 Opening and closing appliances......................................17 D 100 General............................................................................46 A 700 Cofferdams and tank contents.........................................17 D 200 Ships with single or double skin and without other A 800 Forward compartment contents.......................................17 effective longitudinal bulkheads.....................................47 A 900 Minimum bow height......................................................17 D 300 Ships with two effective longitudinal bulkheads............47 A 1000 Access to and within narrow ballast tanks......................18 D 400 Ships with number of effective longitudinal A 1100 Steering gear compartment.............................................18 bulkheads different from two..........................................48 A 1200 Navigation bridge design................................................18 D 500 Strengthening in way of transverse stringers..................49 A 1300 Oil fuel tank protection...................................................18 E. Openings in Longitudinal Strength Members.................49 B. Structural Design Principles..............................................19 E 100 Positions..........................................................................49 B 100 Design procedure............................................................19 E 200 Deduction-free openings.................................................50 B 200 Loading conditions..........................................................19 E 300 Compensations................................................................50 B 300 Hull girder strength.........................................................19 E 400 Reinforcement and shape of smaller openings...............50 B 400 Local bending and shear strength....................................20 E 500 Hatchway corners............................................................50 B 500 Buckling strength............................................................20 E 600 Miscellaneous.................................................................51 B 600 Impact strength................................................................20 B 700 Fatigue.............................................................................21 F. Loading Guidance Information........................................51 B 800 Local vibrations..............................................................21 F 100 General............................................................................51 B 900 Miscellaneous strength requirements..............................21 F 200 Conditions of approval of loading manuals....................51 B 1000 Reliability-based analysis of hull structures...................21 F 300 Condition of approval of loading computer systems......51 DET NORSKE VERITAS Rules for Ships, January 2009 Pt.3 Ch.1 Contents – Page 4 SEC. 6 BOTTOM STRUCTURES................................ 52 E 400 Fatigue control of longitudinals, main frames and 'tween deck frames..............................68 A. General................................................................................52 A 100 Introduction.....................................................................52 SEC. 8 DECK STRUCTURES...................................... 70 A 200 Definitions.......................................................................52 A 300 Documentation................................................................52 A. General.................................................................................70 A 400 Structural arrangement and details..................................52 A 100 Introduction.....................................................................70 A 500 Bottom arrangement........................................................53 A 200 Definitions.......................................................................70 A 300 Documentation................................................................70 B. Design Loads.......................................................................53 A 400 Structural arrangement and details..................................70 B 100 Local loads on bottom structures....................................53 A 500 Construction and initial testing of B 200 Total loads on double bottom..........................................53 watertight decks, trunks etc.............................................71 C. Plating and Stiffeners.........................................................54 B. Design Loads.......................................................................71 C 100 General............................................................................54 B 100 Local loads on deck structures........................................71 C 200 Keel plate........................................................................54 C. Plating and Stiffeners.........................................................73 C 300 Bottom and bilge plating.................................................54 C 100 Strength deck plating......................................................73 C 400 Inner bottom plating........................................................54 C 200 Plating of decks below or above strength deck...............73 C 500 Plating in double bottom floors and C 300 Longitudinals..................................................................73 longitudinal girders.........................................................55 C 400 Transverse beams............................................................73 C 600 Transverse frames...........................................................55 C 700 Bottom longitudinals.......................................................55 D. Girders.................................................................................74 C 800 Inner bottom longitudinals..............................................56 D 100 General............................................................................74 C 900 Stiffening of double bottom floors and girders...............56 D 200 Simple girders.................................................................74 D 300 Complex girder systems..................................................74 D. Arrangement of Double Bottom........................................56 D 100 General............................................................................56 E. Special Requirements.........................................................74 D 200 Double bottom with transverse framing..........................57 E 100 Transverse strength of deck between hatches.................74 D 300 Double bottom with longitudinals...................................57 E 200 Strength of deck outside large hatches............................74 E 300 Pillars in tanks.................................................................75 E. Double Bottom Girder System below E 400 Strengthening against liquid impact pressure in Cargo Holds and Tanks.....................................................57 larger tanks......................................................................75 E 100 Main scantlings...............................................................57 SEC. 9 BULKHEAD STRUCTURES........................... 76 F. Single Bottom Girders........................................................57 F 100 Main scantlings...............................................................57 A. General.................................................................................76 F 200 Local scantlings...............................................................57 A 100 Introduction.....................................................................76 A 200 Definitions.......................................................................76 G. Girders in Peaks..................................................................57 A 300 Documentation................................................................76 G 100 Arrangement....................................................................57 A 400 Structural arrangement and details..................................76 G 200 Scantlings........................................................................58 G 300 Details.............................................................................58 B. Design Loads.......................................................................77 B 100 Local loads on bulkhead structures.................................77 H. Special Requirements.........................................................58 H 100 Vertical struts..................................................................58 C. Plating and Stiffeners.........................................................78 H 200 Strengthening against slamming.....................................58 C 100 Bulkhead plating.............................................................78 H 300 Strengthening for grab loading and C 200 Longitudinals..................................................................78 discharging - Optional class - special features C 300 Vertical and transverse stiffeners on tank, wash, notation IB-X...................................................................59 dry bulk cargo, collision and watertight bulkheads........78 H 400 Docking...........................................................................59 D. Girders.................................................................................79 SEC. 7 SIDE STRUCTURES......................................... 60 D 100 General............................................................................79 D 200 Simple girders.................................................................79 A. General................................................................................60 D 300 Complex girder systems..................................................79 A 100 Introduction.....................................................................60 A 200 Definitions.......................................................................60 E. Special Requirements.........................................................80 A 300 Documentation................................................................60 E 100 Shaft tunnels....................................................................80 A 400 Structural arrangement and details..................................60 E 200 Corrugated bulkheads.....................................................80 E 300 Supporting bulkheads......................................................80 B. Design Loads.......................................................................61 E 400 Strengthening against liquid impact pressure in B 100 Local loads on side structures.........................................61 larger tanks......................................................................80 C. Plating and Stiffeners.........................................................62 SEC. 10 SUPERSTRUCTURE ENDS, DECKHOUSE C 100 Side plating, general........................................................62 SIDES AND ENDS, BULWARKS.................... 82 C 200 Sheer strake at strength deck...........................................62 C 300 Longitudinals..................................................................63 A. General.................................................................................82 C 400 Main frames ...................................................................63 A 100 Introduction.....................................................................82 C 500 'Tween deck frames and vertical peak frames ...............63 A 200 Definitions.......................................................................82 D. Girders.................................................................................64 B. Structural Arrangement and Details................................82 D 100 General............................................................................64 B 100 Structural continuity........................................................82 D 200 Simple girders.................................................................64 B 200 Connections between steel and aluminium.....................82 D 300 Complex girder systems..................................................64 B 300 Miscellaneous..................................................................83 D 400 Cross ties.........................................................................64 C. Design Loads.......................................................................83 E. Special Requirements.........................................................65 C 100 External pressure.............................................................83 E 100 Strengthening against bow impact..................................65 E 200 Stern slamming...............................................................67 D. Scantlings.............................................................................83 E 300 Strengthening against liquid impact D 100 End bulkheads of superstructures and deckhouses, pressure in larger tanks...................................................68 and exposed sides in deckhouses....................................83 DET NORSKE VERITAS Rules for Ships, January 2009 Pt.3 Ch.1 Contents – Page 5 D 200 Protected casings.............................................................83 SEC. 14 STRUCTURES FOR HIGH D 300 Bulwarks.........................................................................83 TEMPERATURE CARGO............................. 101 D 400 Aluminium deckhouses...................................................84 A. General..............................................................................101 SEC. 11 WELDING AND WELD CONNECTIONS.... 85 A 100 Introduction...................................................................101 A 200 Special features notations.............................................101 A. General.................................................................................85 A 300 Documentation..............................................................101 A 100 Introduction.....................................................................85 A 400 Survey and testing.........................................................101 A 200 Definitions.......................................................................85 A 500 Signboards.....................................................................101 B. Materials and Material Protection.................................101 B. Types of Welded Joints.......................................................85 B 100 Hull and tank material...................................................101 B 100 Butt joints........................................................................85 B 200 Insulation material........................................................101 B 200 Lap joints and slot welds.................................................85 B 300 Corrosion protection.....................................................101 B 300 Tee or cross joints...........................................................85 C. Ship Arrangement............................................................101 C. Size of Weld Connections...................................................86 C 100 Location and separation of spaces................................101 C 100 Continuous fillet welds, general.....................................86 C 200 Equipment within the cargo area..................................101 C 200 Fillet welds and penetration welds subject C 300 Surface metal temperature............................................101 to high tensile stresses.....................................................87 C 400 Cargo heating media.....................................................101 C 300 End connections of girders, pillars and cross ties...........87 C 400 End connections of stiffeners..........................................88 D. Load Conditions...............................................................101 C 500 Intermittent welds...........................................................89 D 100 Full and partial cargo conditions...................................101 D 200 Water ballast conditions................................................102 C 600 Slot welds........................................................................89 E. Scantlings of the Cargo area...........................................102 SEC. 12 DIRECT STRENGTH CALCULATIONS ..... 90 E 100 Construction considerations..........................................102 E 200 Thermal stress analysis.................................................102 A. General.................................................................................90 E 300 Acceptable stress level..................................................102 A 100 Introduction.....................................................................90 E 400 Girders...........................................................................103 A 200 Application......................................................................90 A 300 Documentation................................................................90 F. Type of Cargoes................................................................103 F 100 List of cargoes...............................................................103 B. Calculation Methods...........................................................90 B 100 General............................................................................90 SEC. 15 SPECIAL REQUIREMENTS - B 200 Computer program..........................................................91 ADDITIONAL CLASS.................................... 104 B 300 Loading conditions and load application........................91 B 400 Acceptance criteria..........................................................91 A. General..............................................................................104 A 100 Objectives.....................................................................104 C. Global Analysis....................................................................93 A 200 Application....................................................................104 C 100 General............................................................................93 A 300 Class notation combinations.........................................104 C 200 Loading conditions..........................................................93 B. Class Notation NAUTICUS(Newbuilding).....................104 C 300 Acceptance criteria..........................................................93 B 100 General..........................................................................104 B 200 Finite element analysis..................................................105 D. Cargo Hold or Tank Analysis............................................93 B 300 Fatigue strength assessment..........................................105 D 100 General............................................................................93 D 200 Loading conditions and load application........................94 C. Class Notation PLUS-1 and PLUS-2..............................105 D 300 Acceptance criteria..........................................................94 C 100 General..........................................................................105 C 200 Application....................................................................105 E. Frame and Girder Analysis................................................94 C 300 Documentation..............................................................105 E 100 General............................................................................94 C 400 Requirements for fatigue life........................................105 E 200 Loading conditions and load application........................94 E 300 Acceptance criteria..........................................................94 D. Class Notation COAT-1 and COAT-2.............................106 D 100 General..........................................................................106 F. Local Structure Analysis....................................................94 D 200 Application....................................................................106 D 300 Documentation..............................................................106 F 100 General............................................................................94 D 400 Requirements for corrosion prevention........................106 F 200 Loading conditions and load application........................94 D 500 Survey and testing.........................................................107 F 300 Acceptance criteria..........................................................94 E. Class Notation CSA-FLS and CSA-2.............................107 SEC. 13 BUCKLING CONTROL................................... 95 E 100 General..........................................................................107 E 200 Selection of loading conditions.....................................107 A. General.................................................................................95 E 300 Wave load analysis.......................................................107 A 100 Introduction.....................................................................95 E 400 Finite element analysis..................................................108 A 200 Definitions.......................................................................95 E 500 Fatigue strength assessment..........................................108 E 600 Yield and buckling capacity..........................................108 B. Plating..................................................................................95 E 700 Hull girder capacity.......................................................109 B 100 General............................................................................95 B 200 Plate panel in uni-axial compression..............................95 F. Class Notation COAT-PSPC(X)......................................109 B 300 Plate panel in shear.........................................................97 F 100 General..........................................................................109 F 200 Application....................................................................110 B 400 Plate panel in bi-axial compression................................98 F 300 Documentation..............................................................110 B 500 Plate panel in bi-axial compression and shear................98 F 400 Requirements for corrosion prevention systems...........110 C. Stiffeners and Pillars...........................................................98 SEC. 16 FATIGUE CONTROL ................................... 111 C 100 General............................................................................98 C 200 Lateral buckling mode....................................................98 A. General..............................................................................111 C 300 Torsional buckling mode................................................99 A 100 Introduction...................................................................111 C 400 Web and flange buckling..............................................100 A 200 Application....................................................................111 C 500 Transverse beams and girders.......................................100 A 300 Loads.............................................................................111 DET NORSKE VERITAS Rules for Ships, January 2009 Pt.3 Ch.1 Contents – Page 6 A 400 Design criteria...............................................................111 B. Calculation Procedure......................................................112 A 500 Calculation methods......................................................111 B 100 Estimation of ultimate stress.........................................112 A 600 Basic requirements........................................................111 B 200 Calculation of effective width.......................................112 B 300 Ultimate load of stiffened panels..................................112 APP. A ELASTIC BUCKLING AND ULTIMATE B 400 Ultimate strength of simple girders with STRENGTH...................................................... 112 stiffened panel flange....................................................112 B 500 Ultimate strength of complex girders............................113 A. Introduction......................................................................112 A 100 Scope and description...................................................112 DET NORSKE VERITAS Rules for Ships, January 2009 Pt.3 Ch.1 Sec.1 – Page 7 SECTION 1 GENERAL REQUIREMENTS A. Classification D = moulded depth defined as the vertical distance in m from baseline to moulded deckline at the uppermost A 100 Application continuous deck measured amidships. D = least moulded depth taken as the vertical distance in m 101 The rules in this chapter apply to steel hull structures for F from the top of the keel to the top of the freeboard deck assignment of the main class for ships with length 100 metres beam at side. and above, except for oil tankers and bulk carriers with man- datory class notation CSR. Application of the CSR notation is In ships having rounded gunwales, the moulded depth described in Pt.8 Ch.1 for oil tankers and Pt.8 Ch.2 for bulk shall be measured to the point of intersection of the carriers. Sec.15 may be applied to vessels with CSR notation. moulded lines of the deck and side shell plating, the lines extending as though the gunwale was of angular 102 Applicable rules for assignment of main class for tank- design. ers with class notation CSR are given in Pt.5 Ch.3. Where the freeboard deck is stepped and the raised part 103 The rules also apply to aluminium structures and wood- of the deck extends over the point at which the mould- en decks to the extent that these materials are acceptable as al- ed depth shall be determined, the moulded depth shall ternative materials. be measured to a line of reference extending from the A 200 Class notations lower part of the deck along a line parallel with the raised part. 201 The class notations applicable for the assignment of the T = mean moulded summer draught in m. main class are described in Pt.1 Ch.1 Sec.1. Δ = moulded displacement in t in salt water (density 1.025 202 The following special features notations are specified in t/m3) on draught T. this chapter: C = block coefficient, B Δ DAT(-X°C) lowest design ambient temperature (Sec.2 B401) = ----------------------------- 1.025LBT ICM increased corrosion margin (Sec.2 D300) HL(ρ) tanks for heavy liquid (Sec.4 C301) For barge rigidly connected to a push-tug C shall be B DK(+) decks for heavy cargo (Sec.4 C401) calculated for the combination barge/ push-tug. C = block coefficient as defined in the International Con- HA(+) hatches for heavy cargo (Sec.4 C401) BF vention of Load Lines: IB-X inner bottom strengthened for grab loading and discharging (Sec.6 H300) ∇ = -------------------- BIS built for in-water survey (D100) L BT F F ∇ = volume of the moulded displacement, excluding boss- ings, taken at the moulded draught T . F B. Definitions TF = 85% of the least moulded depth. V = maximum service speed in knots, defined as the great- B 100 Symbols est speed which the ship is designed to maintain in service at her deepest seagoing draught. 101 The following symbols are used: g = standard acceleration of gravity. 0 = 9.81 m/s2 L = length of the ship in m defined as the distance on the f = material factor depending on material strength group. summer load waterline from the fore side of the stem 1 See Sec.2. to the axis of the rudder stock. t = corrosion addition as given in Sec.2 D200 and D300, k L shall not be taken less than 96%, and need not to be as relevant taken greater than 97%, of the extreme length on the x = axis in the ship's longitudinal direction. summer load waterline. For ships with unusual stern y = axis in the ship's athwartships direction. and bow arrangement, the length L will be especially z = axis in the ship's vertical direction. considered. E = modulus of elasticity of the material, F.P. = the forward perpendicular is the perpendicular at the in- = 2.06 · 105 N/mm2 for steel tersection of the summer load waterline with the fore side = 0.69 · 105 N/mm2 for aluminium alloy. of the stem. For ships with unusual bow arrangements the C = wave load coefficient given in Sec.4 B200. position of the F.P. will be especially considered. W A.P. = the after perpendicular is the perpendicular at the after Amidships = the middle of the length L. end of the length L. L = length of the ship as defined in the International Con- B 200 Terms F vention of Load Lines: 201 Linear and angular motions of the ship are defined as The length shall be taken as 96 per cent of the total follows: length on a waterline at 85 per cent of the least mould- — surge is the linear motion along the x-axis ed depth measured from the top of the keel, or as the — sway is the linear motion along the y-axis length from the fore side of the stem to the axis of the — heave is the linear motion along the z-axis rudder stock on that waterline, if that be greater. In — roll is the angular motion about the x-axis ships designed with a rake of keel the waterline on — pitch is the angular motion about the y-axis which this length is measured shall be parallel to the — yaw is the angular motion about the z-axis. designed waterline. B = greatest moulded breadth in m, measured at the sum- 202 Moulded deck line, Rounded sheer strake, Sheer strake, mer waterline. and Stringer plate are as defined in Fig.1. DET NORSKE VERITAS Rules for Ships, January 2009 Pt.3 Ch.1 Sec.1 – Page 8 209 Deck structure is defined as deck plating with stiffeners, DECK LINE girders and supporting pillars. MOULDED 210 Bulkhead structure is defined as transverse or longitudi- ROUNDED nal bulkhead plating with stiffeners and girders. SHEER STRAKE Watertight bulkhead is a collective term for transverse bulk- heads required according to Sec.3 A. Cargo hold bulkhead is a boundary bulkhead for cargo hold. Tank bulkhead is a boundary bulkhead in tank for liquid cargo, ballast or bunker. DECK LINE MOULDED Wash bulkhead is a perforated or partial bulkhead in tank. STRINGER PLATE 211 Forepeak and afterpeak are defined as the areas forward SHEER STRAKE of collision bulkhead and aft of after peak bulkhead, respec- tively, up to the heights defined in Sec.3 A500. Fig. 1 212 Superstructure Deck corners a) A superstructure is a decked structure on the freeboard deck, extending from side to side of the ship or with the 203 The freeboard assigned is the distance measured verti- side plating not being inboard of the shell plating more cally downwards amidships from the upper edge of the deck than 4 per cent of the breadth (B). A raised quarter deck is line to the upper edge of the related load line. regarded as a superstructure. 204 The freeboard deck is normally the uppermost complete b) An enclosed superstructure is a superstructure with: deck exposed to weather and sea, which has permanent means of closing all openings in the weather part thereof, and below i) enclosing bulkheads of efficient construction, which all openings in the sides of the ship are fitted with per- ii) access openings, if any, in these bulkheads fitted with manent means of watertight closing. In a ship having a discon- doors complying with the requirements of Ch.3 Sec.6 tinuous freeboard deck, the lowest line of the exposed deck and B101, the continuation of that line parallel to the upper part of the deck is taken as the freeboard deck. At the option of the owner iii) all other openings in sides or ends of the superstruc- and subject to the approval of the Administration, a lower deck ture fitted with efficient weathertight means of clos- may be designated as the freeboard deck provided it is a com- ing. plete and permanent deck continuous in a fore and aft direction at least between the machinery space and peak bulkheads and A bridge or poop shall not be regarded as enclosed unless access is provided for the crew to reach machinery and continuous athwartships. When this lower deck is stepped the other working spaces inside these superstructures by alter- lowest line of the deck and the continuation of that line parallel native means which are available at all times when bulk- to the upper part of the deck is taken as the freeboard deck. head openings are closed. When a lower deck is designated as the freeboard deck, that part of the hull which extends above the freeboard deck is c) The height of a superstructure is the least vertical height treated as a superstructure so far as concerns the application of measured at side from the top of the superstructure deck the conditions of assignment and the calculation of freeboard. beams to the top of the freeboard deck beams. It is from this deck that the freeboard is calculated. d) The length of a superstructure (S) is the mean length of the 205 Strength deck is in general defined as the uppermost part of the superstructure which lies within the length (L). continuous deck. A superstructure deck which within 0.4 L e) A long forward superstructure is defined as an enclosed amidships has a continuous length equal to or greater than forward superstructure with length S equal to or greater than 0.25 L. ⎛B ⎞ 3 ----+H (m) ⎝2 ⎠ 213 A flush deck ship is one which has no superstructure on the freeboard deck. shall be regarded as the strength deck instead of the covered 214 Girder is a collective term for primary supporting mem- part of the uppermost continuous deck. bers. Tank girders with special names are shown in Fig.2. H = height in m between the uppermost continuous deck Other terms used are: and the superstructure deck in question. — floor (a bottom transverse girder) Another deck may be defined as the strength deck after special — stringer (a horizontal girder). consideration of its effectiveness. 215 Stiffener is a collective term for a secondary supporting 206 Double bottom structure is defined as shell plating with member. Other terms used are: stiffeners below the top of the inner bottom and other elements below and including the inner bottom plating. Note that slop- — frame ing hopper tank top side shall be regarded as longitudinal bulk- — bottom longitudinal head. — inner bottom longitudinal 207 Single bottom structure is defined as shell plating with — reversed frame (inner bottom transverse stiffener) stiffeners and girders below the upper turn of bilge. — side longitudinal 208 Side structure is defined as shell plating with stiffeners — beam and girders between the bottom structure and the uppermost — deck longitudinal deck at side. — bulkhead longitudinal. DET NORSKE VERITAS Rules for Ships, January 2009 Pt.3 Ch.1 Sec.1 – Page 9 SIDE TANK DECK TRANSVERSE f (x) x SIDE VERTICAL SENTRE TANK DECK TRANSVERSE DECK CENTRE LINE GIRDER DECK SIDE exceedance GIRDER probability LONG. BULKHEAD cumulative VERTICAL probability p 1-p CROSS TIE x x CENTRE TANK p BOTTOM TRANSVERSE BOTTOM CENTRE (p quantile of X = Upper p quantile of X LINE GIRDER = Lower (1– p) quantile of X) BOTTOM SIDE GIRDER Fig. 3 SIDE TANK Probability density function BOTTOM TRANSVERSE Fig. 2 Tank girders C. Documentation C 100 Plans and particulars 216 Probability density function f(x). The probability that a 101 The following plans are normally to be submitted for ap- realisation of a continuous random variable x falls in the inter- proval: val (x, x+dx) is f(x)dx. f(x) is the derivative of the cumulative probability function F(x). — midship section including main particulars (L, B, D, T, C ), maximum service speed V 217 Cumulative probability F(x) is defined as: B — deck and double bottom plans including openings — longitudinal section x — shell expansion and framing including openings and ex- F(x) = ∫ f(x)dx tent of flat part of bottom forward –∞ — watertight bulkheads including openings 218 Exceedance probability Q(x) is defined as: — cargo tank structures — deep tank structures — engine room structures including tanks and foundations Q(x) = 1 – F(x) for heavy machinery components — afterpeak structures 219 Probability of exceedance, or exceedance probability — forepeak structures may be illustrated by the following example: x shall be taken — superstructures and deckhouses including openings, at a probability of exceedance of q, means that the variable, x, — hatchways, hatch covers, doors in the ship's sides and ends shall be taken as the value, x , defined as the upper q quantile q — supporting structures for containers and container secur- in the long term distribution of x. ing equipment 220 Quantile. The p quantile may be defined as the value, x , — arrangement of cathodic protection. p of a random variable x, which correspond to a fraction p of the Identical or similar structures in various positions should pref- outcomes of the variable. erably be covered by the same plan. x 102 Plans and particulars for closing appliances (doors, p hatches, windows etc.) to be submitted for approval are speci- F(x ) = ∫ f(x)dx = p p fied in Ch.3 Sec.6. –∞ 103 Loading guidance information (loading manual and I.e. x is the p quantile of the variable x. One may denote x as loading computer system) shall be approved and certified in p p the lower p quantile of x, or alternatively as the upper 1– p accordance with Sec.5 F. quantile of x. 104 The following plans shall be submitted for information: B 300 Ship types — general arrangement — engine room arrangement 301 A passenger ship is a ship which carries more than 12 — tank arrangement passengers. — capacity plan 302 A cargo ship is any ship which is not a passenger ship. — body plan, hydrostatic curves or tables. 303 A tanker is a cargo ship constructed or adapted for the 105 For instrumentation and automation, including compu- carriage in bulk of liquid cargoes. ter based control and monitoring, see Pt.4 Ch.9 Sec.1. DET NORSKE VERITAS Rules for Ships, January 2009 Pt.3 Ch.1 Sec.1 – Page 10 C 200 Specifications and calculations D 200 Documentation 201 All longitudinal strength calculations shall be submitted 201 Plans giving particulars on the following shall be sub- with relevant information: mitted: — markings of side and bottom - for approval — maximum stillwater bending moments and shear forces as — arrangement of openings in sides and bottom below the defined in Sec.5 B102 deepest load waterline, bottom plugs, echo sounder and — still water bending moment limits any other underwater equipment - for information — mass of light ship and its longitudinal distribution — details showing how rudder bearing clearances can be — buoyancy data measured - for information — cargo capacity in t — arrangement of any impressed current system - for infor- — cargo, ballast and bunker distribution, including maxi- mation. mum mass of cargo (t) in each compartment. The plans shall be available onboard. 202 Information which may be necessary for local strength Guidance note: calculations: Means should be provided to enable the diver to confirm that the sea suction openings are clear. — minimum and maximum ballast draught and correspond- Hinged sea suction grids will facilitate this operation, preferably ing trim with revolving weight balance or with a counter weight, and se- — load on deck, hatch covers and inner bottom cured with bolts practical for dismantling and fitting while the ship is afloat. — stowage rate and angle of repose of dry bulk cargo — maximum density of intended tank contents ---e-n-d---of---G-u- i-d-a-n-c-e---n-o-t-e--- — height of air pipes D 300 Markings of ship’s sides and bottom — mass of heavy machinery components — design forces for securing devices on hatch covers and 301 The underwater body shall be marked in such a way that external doors the surveyor can identify the location of any observations — design forces for cargo securing and container supports made. Transverse and longitudinal reference lines of approxi- mate length 300 mm and width 25 mm shall be applied as — any other local loads or forces which will affect the hull marking. The marks shall be made permanent welding or sim- structure. ilar and painted in a contrasting colour. 203 Specifications for corrosion prevention systems for wa- Marking shall normally be placed as follows: ter ballast tanks, comprising selection, application and mainte- nance, shall be submitted for as defined in Ch.3 Sec.7. — at flat bottom in way of intersections of tank bulkheads or watertight floors and girders C 300 Specific purpose documentation — at ship’s sides in way of the positions of transverse bulk- heads (the marking need not be extended more than 1 m 301 For hull equipment and appendages, see Ch.3. above bilge plating) — the intersection between tank top and watertight floors in 302 For additional class notations, see Pt.5 and Pt.6. way of ship’s sides 303 For installations for which no notation is available or re- — all openings for sea suctions and discharge quested, all relevant information or documentation affecting — letter and number codes shall be applied on the shell for hull structures or ship safety shall be submitted. identification of tanks, sea suctions and discharges. D 400 Rudder 401 Bearing materials shall be stainless steel, bronze or an D. Ships Built for In-Water Survey of the Ship's approved type of synthetic material and shall satisfy the re- Bottom and Related Items quirements in Ch.3 Sec.2. 402 For water lubricated bearings, arrangements shall be D 100 General made for measuring of rudder stock and pintle clearances 101 Ships built in accordance with the following require- while the ship is afloat. ments may be given the notation BIS. D 500 Tailshaft 102 The BIS notation indicates that the ship is prepared for 501 The tailshaft shall be designed to minimum 5 years sur- in-water survey. vey interval, ref. Pt.7 Ch.1 Sec.1 A. Guidance note: D 600 Thrusters The conditions under which in-water survey is allowed are given in Pt.7 Ch.1 Sec.A. 601 Thrusters shall have 5 year survey interval or alterna- tively the reduced scope survey, as required in Pt.7 Ch.1 Sec.5 ---e-n-d---of---G-u- i-d-a-n-c-e---n-o-t-e--- C, shall be possible while the ship is afloat. DET NORSKE VERITAS