SIST EN ISO 12215-9:2012

Small craft - Hull construction and scantlings - Part 9: Sailing craft appendages (ISO 12215-9:2012)

This part of ISO 12215 defines the loads and specifies the scantlings of sailing craft appendages on monohull sailing craft with a length of hull, LH, of up to 24 m, measured according to ISO 8666. It gives - design stresses, - the structural components to be assessed, - load cases and design loads for keel, centreboard and their attachments, - computational methods and modelling guidance, and - the means for compliance with its provisions.

Kleine Wasserfahrzeuge - Rumpfbauweise und Dimensionierung - Teil 9: Segelboote - Anhänge und Takelagezubehör (ISO 12215-9:2012)

Dieser Teil von ISO 12215 betrifft die Bestimmungen der Lasten und Dimensionierung von Segelfahrzeuganhängen und Takelagezubehör auf Wasserfahrzeugen mit einer Rumpflänge (LH) bis 24 m,  nach ISO 8666.
Betroffen sind
¾   Lasten/Dimensionierung von Anhängen, wie z. B. Ballastkiele, Kielschwerter, usw. (Abschnitt 6 bis 9);
¾   Lasten/Dimensionierung von Takelagezubehör, wie z. B. Püttingeisen, Zugstangen, Mastsäulen und Maststufen (Abschnitt 10 bis 12).
Dieser Teil von ISO 12215 behandelt nur die gängigsten Anordnungen. Andere Anordnungen einschließlich quer laufend geneigte Kiele liegen außerhalb des Anwendungsbereichs von diesem Teil von ISO 12215, aber die in diesem Dokument vorliegende Lasten und Sicherheitsfaktoren dürfen als Basis zur Berechnung benutzt werden.
ANMERKUNG 1   Geneigte Kiele benötigen möglicherweise höhere Sicherheitsfaktoren, da sie im Wesentlichen für längere Zeiten als in 6.1 vorgesehen in einem „near knockdown“ Zustand arbeiten.
In vielen Fällen muss dieser Teil von ISO 12215 in Verbindung mit Teil 5 für Druck- und Dimensionierungsbestimmung benutzt werden, sowie Teil 6 für Einzelheiten und Teil 8 für Ruder.
ANMERKUNG 2   Dimensionierungen, die sich aus dieser Internationalen Norm ergeben, sind in erster Linie für Freizeitwasserfahrzeuge einschließlich Charterboote gedacht.

Petits navires - Construction de coques et échantillonnage - Partie 9: Appendices des bateaux à voiles (ISO 12215-9:2012)

L'ISO 12215-9:2011 définit les chargements et spécifie l'échantillonnage des appendices des bateaux à voiles d'une longueur de coque, LH, mesurée conformément à l'ISO 8666, inférieure ou égale à 24 m. Elle fournit: les contraintes de conception, les éléments structurels à évaluer, les cas de chargement et les charges de conception pour la quille, la dérive et leurs éléments de liaison, les méthodes de calcul et des instructions de modélisation et les moyens de se conformer à ses dispositions.

Mala plovila - Konstrukcija trupa in dimenzioniranje - 9. del: Dodatni pribor jadrnic (ISO 12215-9:2012)

Ta del standarda ISO 12215 določa obremenitve in dimenzioniranje dodatnega pribora jadrnic na jadrnicah z enim trupom, pri čemer dolžina trupa (LH), merjena v skladu s standardom ISO 8666, ne presega 24 m. Navaja: – konstrukcijske napetosti, – sestavne dele konstrukcije, ki jih je treba oceniti, – primere obremenitve in konstrukcijske obremenitve za gredelj, premični gredelj in njune priključke, – računalniške metode in navodila za modeliranje ter – načine skladnosti z določbami standarda.

General Information

• Status: Withdrawn
• Publication Date: 16-Jul-2012
• Withdrawal Date: 10-Oct-2018
• ICS: 47.020.10 - Hulls and their structure elements
• ICS: 47.080 - Small craft
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 11-Oct-2018
• Due Date: 03-Nov-2018
• Completion Date: 11-Oct-2018
• Directive: 2003/44/EC - Approximation of the laws, regulations and administrative provisions of the Member States relating to recreational craft
• Directive: 2013/53/EU - Directive 2013/53/EU of the European Parliament and of the Council of 20 November 2013 on recreational craft and personal watercraft and repealing Directive 94/25/EC
• Directive: 94/25/EC - Directive 94/25/EC of the European Parliament and of the Council of 16 June 1994 on the approximation of the laws, regulations and administrative provisions of the Member States relating to recreational craft
• Mandate: M/075 - Revised mandate to CEN for standardization in the field of recreational craft
• Ref Project: EN ISO 12215-9:2012 - Small craft - Hull construction and scantlings - Part 9: Sailing craft appendages (ISO 12215-9:2012)

Relations

• Replaced By: SIST EN ISO 12215-9:2018 - Small craft - Hull construction and scantlings - Part 9: Sailing craft appendages (ISO 12215-9:2012)
• Effective Date: 10-Oct-2018
• Replaced By: SIST EN ISO 12215-9:2018 - Small craft - Hull construction and scantlings - Part 9: Sailing craft appendages (ISO 12215-9:2012)
• Effective Date: 08-Jun-2022
• Revised: SIST EN ISO 12215-9:2018 - Small craft - Hull construction and scantlings - Part 9: Sailing craft appendages (ISO 12215-9:2012)
• Effective Date: 07-Jun-2017

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 12215-9:2012
01-september-2012
Mala plovila - Konstrukcija trupa in dimenzioniranje - 9. del: Dodatni pribor jadrnic
(ISO 12215-9:2012)
Small craft - Hull construction and scantlings - Part 9: Sailing craft appendages (ISO
12215-9:2012)
Kleine Wasserfahrzeuge - Rumpfbauweise und Dimensionierung - Teil 9: Segelboote -
Anhänge und Takelagezubehör (ISO 12215-9:2012)
Petits navires - Construction de coques et échantillonnage - Partie 9: Appendices des
bateaux à voiles (ISO 12215-9:2012)
Ta slovenski standard je istoveten z: EN ISO 12215-9:2012
ICS:
47.020.10 Ladijski trupi in njihovi Hulls and their structure
konstrukcijski elementi elements
47.080 ýROQL Small craft
SIST EN ISO 12215-9:2012 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 12215-9:2012

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SIST EN ISO 12215-9:2012


EUROPEAN STANDARD
EN ISO 12215-9

NORME EUROPÉENNE

EUROPÄISCHE NORM
June 2012
ICS 47.080
English Version
Small craft - Hull construction and scantlings - Part 9: Sailing
craft appendages (ISO 12215-9:2012)
Petits navires - Construction de coques et échantillonnage - Kleine Wasserfahrzeuge - Rumpfbauweise und
Partie 9: Appendices des bateaux à voiles (ISO 12215- Dimensionierung - Teil 9: Anhänge von Segelbooten (ISO
9:2012) 12215-9:2012)
This European Standard was approved by CEN on 9 April 2012.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12215-9:2012: E
worldwide for CEN national Members.

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SIST EN ISO 12215-9:2012
EN ISO 12215-9:2012 (E)
Contents Page
Foreword .3
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 94/25/EC as amended by Directive 2003/44/EC .4

2

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SIST EN ISO 12215-9:2012
EN ISO 12215-9:2012 (E)
Foreword
This document (EN ISO 12215-9:2012) has been prepared by Technical Committee ISO/TC 188 "Small craft".
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by December 2012, and conflicting national standards shall be withdrawn
at the latest by December 2012.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association, and supports essential requirements of EU Directive.
For relationship with EU Directive, see informative Annex ZA, which is an integral part of this document.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 12215-9:2012 has been approved by CEN as a EN ISO 12215-9:2012 without any
modification.
3

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SIST EN ISO 12215-9:2012
EN ISO 12215-9:2012 (E)
Annex ZA
(informative)

Relationship between this European Standard and the Essential
Requirements of EU Directive 94/25/EC as amended by
Directive 2003/44/EC
This European Standard has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association to provide one means of conforming to Essential Requirements of
the New Approach Directive 94/25/EC as amended by 2003/44/EC on Recreational Craft.
Once this standard is cited in the Official Journal of the European Union under that Directive and has been
implemented as a national standard in at least one Member State, compliance with the normative clauses of
this standard given in Table ZA.1 confers, within the limits of the scope of this standard, a presumption of
conformity with the relevant Essential Requirements of that Directive and associated EFTA regulations.
Table ZA.1: Correspondence between this European Standard and Directive 94/25/EC as amended by
Directive 2003/44/EC
Clauses/sub-clauses of this Essential requirements (ERs) of Qualifying remarks/Notes
European Standard EU Directive 94/25/EC as amended
by Directive 2003/44/EC
All clauses Annex I, A, Clause 3.1 The standard provides
requirements for strength of
monohull sailing boat appendages
with conventional keel
configurations

WARNING: Other requirements and other EU Directives may be applicable to the product(s) falling within the
scope of this standard.

4

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SIST EN ISO 12215-9:2012

INTERNATIONAL ISO
STANDARD 12215-9
First edition
2012-06-15


Small craft — Hull construction and
scantlings —
Part 9:
Sailing craft appendages
Petits navires — Construction de la coque et échantillonnage —
Partie 9: Appendices des bateaux à voiles




Reference number
ISO 12215-9:2012(E)
©
ISO 2012

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SIST EN ISO 12215-9:2012
ISO 12215-9:2012(E)

COPYRIGHT PROTECTED DOCUMENT


©  ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56  CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland

ii © ISO 2012 – All rights reserved

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SIST EN ISO 12215-9:2012
ISO 12215-9:2012(E)
Contents Page
Foreword . iv
Introduction . v
1  Scope . 1
2  Normative references . 1
3  Terms and definitions . 2
4  Symbols . 3
5  Design stresses . 4
6  Structural components to be assessed . 6
7  Load cases . 6
7.1  General . 6
7.2  Load case 1 — Fixed keel at 90° knockdown . 7
7.3  Load case 2 — Canted keel steady load at 30° heel with dynamic overload factor . 8
7.4  Load case 3 — Keelboat vertical pounding . 9
7.5  Load case 4 — Keelboat longitudinal impact . 10
7.6  Load case 5 — Centreboard on capsize recoverable dinghies . 11
7.7  Load case 6 — Centreboard or dagger board upwind . 11
7.8  Other load cases . 12
8  Computational methods . 15
8.1  General . 15
8.2  General guidance for assessment by 3D numerical procedures . 15
8.3  Assessment by strength of materials/non-computational-based methods . 16
9  Compliance . 16
Annex A (normative) Application declaration . 18
Annex B (informative) Information on metal for appendages and fasteners and
“established practice” for fastening and welding . 19
Annex C (informative)  “Established practice” structural arrangement for ballast keels . 30
Annex D (informative) “Established practice” calculation of keel fin strength (fixed or canting)
and fixed ballast keel connected by bolts . 44
Annex E (informative) Geometrical properties of some typical appendage foil shapes . 61
Annex F (informative) Simplified fatigue strength assessment . 64
Bibliography . 76

© ISO 2012 – All rights reserved iii

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SIST EN ISO 12215-9:2012
ISO 12215-9:2012(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 12215-9 was prepared by Technical Committee ISO/TC 188, Small craft.
ISO 12215 consists of the following parts, under the general title Small craft — Hull construction and
scantlings:
 Part 1: Materials: Thermosetting resins, glass-fibre reinforcement, reference laminate
 Part 2: Materials: Core materials for sandwich construction, embedded materials
 Part 3: Materials: Steel, aluminium alloys, wood, other materials
 Part 4: Workshop and manufacturing
 Part 5: Design pressures for monohulls, design stresses, scantlings determination
 Part 6: Structural arrangements and details
 Part 7: Scantling determination of multihulls
 Part 8: Rudders
 Part 9: Sailing craft appendages
iv © ISO 2012 – All rights reserved

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SIST EN ISO 12215-9:2012
ISO 12215-9:2012(E)
Introduction
The reason underlying the preparation of this part of ISO 12215 is that standards and recommended practices
for loads on the hull and the dimensioning of small craft differ considerably, thus limiting the general worldwide
acceptability of craft.
The loss of a keel leading to craft capsize is one of the major casualty hazards on sailing craft and therefore
the structural efficiency of all elements of the keel and its connection to the craft is paramount.
This part of ISO 12215 specifies the design loads and their associated stress factors. The user then has a
choice between one or the other of the following available options for assessing the structural arrangement.
a) Use of advanced engineering methods which allow the structure to be modelled as three-dimensional:
suitable methods include finite element analysis and subsets thereof such as matrix displacement or
framework methods. General guidance is provided on modelling assumptions within this part of
ISO 12215.
b) Use of simplified, generally two-dimensional, “strength of materials”-based stress equations: These are
presented in Annexes B to F and, if this option is chosen, use of the equations will be necessary to fulfil
the requirements of this part of ISO 12215.
This part of ISO 12215 has been developed applying present practice and sound engineering principles. The
design loads and criteria of this part of ISO 12215 may be used with the scantling determination equations of
this part of ISO 12215 or using equivalent engineering methods as indicated in a), above.
The dimensioning according to this part of ISO 12215 is regarded as reflecting current practice, provided the
craft is correctly handled in the sense of good seamanship and equipped and operated at a speed appropriate
to the prevailing sea state.
During the latter stages of the development of the ISO 12215 series, and after publication of key parts, a
number of authorities adopted this International Standard for the assessment of high-performance racing
yachts. While, in theory, a category A blue-water cruising yacht could experience the same loads as a
competitive racing yacht, the latter has not been the principal focus of ISO 12215. Consequently, designers
are strongly cautioned against attempting to design high-performance racing craft such that nearly all
structural components only just comply.
© ISO 2012 – All rights reserved v

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SIST EN ISO 12215-9:2012

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SIST EN ISO 12215-9:2012
INTERNATIONAL STANDARD ISO 12215-9:2012(E)

Small craft — Hull construction and scantlings —
Part 9:
Sailing craft appendages
1 Scope
This part of ISO 12215 defines the loads and specifies the scantlings of sailing craft appendages on monohull
sailing craft with a length of hull, L , of up to 24 m, measured according to ISO 8666. It gives
H
 design stresses,
 the structural components to be assessed,
 load cases and design loads for keel, centreboard and their attachments,
 computational methods and modelling guidance, and
 the means for compliance with its provisions.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 898-1, Mechanical properties of fasteners made of carbon steel and alloy steel — Part 1: Bolts, screws
and studs with specified property classes — Coarse thread and fine pitch thread
ISO 3506-1, Mechanical properties of corrosion-resistant stainless steel fasteners — Part 1: Bolts, screws and
studs
ISO 8666, Small craft — Principal data
ISO 12215-3, Small craft — Hull construction and scantlings — Part 3: Materials — Steel, aluminium alloys,
wood, other materials
ISO 12215-5:2008, Small craft — Hull construction and scantlings — Part 5: Design pressures for monohulls,
design stress, scantlings determination
ISO 12215-6:2008, Small craft — Hull construction and scantlings — Part 6: Structural arrangements and
details
ISO 12217-2, Small craft — Stability and buoyancy assessment and categorization — Part 2: Sailing boats of
hull length greater than or equal to 6 m
© ISO 2012 – All rights reserved 1

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SIST EN ISO 12215-9:2012
ISO 12215-9:2012(E)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
design category
sea and wind conditions for which a craft is assessed to be suitable, provided the craft is correctly handled in
the sense of good seamanship and operated at a speed appropriate to the prevailing sea state
3.1.1
design category A
“ocean category”
category of craft considered suitable to operate in seas with significant wave heights above 4 m and wind
speeds in excess of Beaufort Force 8, but excluding abnormal conditions such as hurricanes
3.1.2
design category B
“offshore category”
category of craft considered suitable to operate in seas with significant wave heights up to 4 m and winds of
Beaufort Force 8 or less
3.1.3
design category C
“inshore category”
category of craft considered suitable to operate in seas with significant wave heights up to 2 m and a typical
steady wind force of Beaufort Force 6 or less
3.1.4
design category D
“sheltered waters category”
category of craft considered suitable to operate in waters with significant wave heights up to and including
0,3 m with occasional waves of 0,5 m height, for example from passing vessels, and a typical steady wind
force of Beaufort 4 or less
3.2
loaded displacement mass
m
LDC
mass of the craft, including all appendages, when in the fully loaded ready-for-use condition as defined in
ISO 8666
NOTE 1 The displacement includes all possible options (generator, air conditioning, etc.).
NOTE 2 The loaded displacement mass is expressed in kilograms.
3.3
sailing craft
2/3
craft for which the primary means of propulsion is wind power, having A  0,07(m ) where A is the total
S LDC S
profile area of all sails that may be set at one time when sailing closed hauled, as defined in ISO 8666 and
expressed in square metres
NOTE 1 For the headsails, A considers the area of the fore triangle.
S
NOTE 2 The area of the wing-mast(s) is included in A .
S
3.4
mass of keel
m
KEEL
mass of the ballast keel, i.e. keel fin plus bulb, where fitted, and, for twin or multiple keels, of a single keel
NOTE The mass of keel is expressed in kilograms.
2 © ISO 2012 – All rights reserved

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SIST EN ISO 12215-9:2012
ISO 12215-9:2012(E)
4 Symbols
For the purposes of this document, unless specifically otherwise defined, the symbols given in Table 1 apply.
Table 1 — Symbols, coefficients, parameters in the main core of ISO 12215-9
(Sub)clause/table
Symbol Unit Designation/meaning of symbol
concerned
2
A
m Area of fully deployed centreboard 7.7.1
CB
Reference sail area (mainsail + fore triangle + wing mast) as per
2
A
m 7.7.1
S
ISO 12217-2
Distance along keel centreline, from centre of gravity (CG) of keel to keel
a m 7
junction with hull or tuck
c m Distance along keel centreline from keel junction to floor mid-height 7
c
m Average value of c for several floors 7.5
a
e
m Proportion of the total side force taken by the centreboard 7.7.1
F
N Design force with i according to load case 7
i
2 2
g m/s Acceleration of gravity = 9,81 m/s 7
h Height of centre of area of A
m 7.7.1
CE S
h
m Height of keel between its bottom and hull connection 7.5.2
K
h Height of application of force F (load case 4)
m 7.5.2
4
F4
k 1 Design category coefficient 5, Table 2
DC
k
1 Load case coefficient 5, Table 3
LC
k
1 Length displacement coefficient 7.7.1
LD
k
1 Material coefficient 5, Table 2
MAT
L m Length of waterline in m conditions 7.5.2, 7.7.1
WL LDC
m
kg See definition 3.2 3.2, 7
LDC
m
kg See definition 3.4 3.4, 7.4
KEEL
M
Nm Design bending moment, with index I and J according to load case 7
IJ
2
st N/mm 5
Stress, which can be  or  , and where i can be LIM, d, u, y, yw or yu
i
 deg. Angle of attack of centreboard foil 7.7

% Elongation at break Table 2
R
 deg. Angle between keel axis and centreline for canting keels 7.3
© ISO 2012 – All rights reserved 3

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SIST EN ISO 12215-9:2012
ISO 12215-9:2012(E)
5 Design stresses
The maximum stress shall be calculated for each relevant structural component and load case.
The design stress, st , is the relevant limit stress multiplied by various stress coefficients:
d
2
stst k kk N/mm (1)
dLIM MAT LC DC
where
st is the limit stress, with st representing either , in direct stress, orin shear stress, and index
LIM
LIM is as follows:
 for metal in unwelded state or well clear of HAZ, min sts;0,5t , where index y is the
 
y u
yield strength and index u is the ultimate strength, i.e.  , for direct stress,  , for
yu yu
shear stress and  , for bearing stress;
by bu
 for metal within HAZ, min st ;0,5 st , where index y is the yield strength and index u
 
yw uw
is the ultimate strength, i.e.  ,, for direct stress,  , for shear stress and for
yw uw yw uw
, bearing stress;
byw buw
 for wood and fibre-reinforced polymer (FRP), the ultimate strength in tensile  ,
tu
compressive  , flexural  , bearing,  or shear stress  ;
cu fu bu u
k is the material coefficient as defined in Table 2, with the design stress adjusted according to the
MAT
material;
k is the load case coefficient as defined in Table 3, with the design stress adjusted according to
LC
the load case;
k is the design category coefficient as defined in Table 2, with allowance for an increase in design
DC
stress for lower design categories due to less severe dynamic loadings than in higher design
categories.
Table 2 gives details on these variables.
The values of st — i.e. ,, for unwelded metals,  ,,, for welded metals in a
LIM yu u yw uw yw uw
heat-affected zone (HAZ), or  ,  ,  ,  or  for wood and FRP — shall be taken
tu cu fu bu u
 in accordance with ISO 12215-5:2008, i.e. according to tests or default values specified in its Annex C for
FRP, its Annex D for sandwich core, and its Annex E for laminated wood and plywood,
 in accordance with Annex B for the listed metals, including, where relevant, ISO 3506-1 for stainless steel
fasteners and ISO 898-1 for carbon steel or alloy steel fasteners, and
 for other metals, either from a recognized standard or from tests made in accordance with the relevant
International Standard.
4 © ISO 2012 – All rights reserved

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SIST EN ISO 12215-9:2012
ISO 12215-9:2012(E)
Table 2 — Design stresses and stress coefficients
Variable Material/designation Value
b,c
a
min. sts;0,5t
Metals, unwelded or well clear of HAZ 
yu
a b,c
st min. st ;0,5 st
Metals, within HAZ, in welded condition

LIM yw uw
c
 ,, , and as relevant
Wood or FRP as dictated by sense of applied stress
uc ut uf ub u
Stress factor
Metals with elongation at break,  % ≥ 7
0,75
R
k
MAT
d
Metals with elongation at break,  % <7 min.(0,0625 + 0,3125;0,75)
R R
Wood and FRP 0,33
k
Stress factor (see Table 3)
LC
Stress factor
k
Craft of design categories A and B 1,00
DC
Craft of design categories C and D 1,25
a
Generally, the heat-affected zone is considered as being 50 mm from the weld (see also the Note in F.3.4.3).
b
For metals, 0,58  .
c
Bearing stress depends on material type (Ref [8] gives   = 2,8 for Glass CSM and 0,91 for roving), metal regulation usually
ub uc
gives 2,4 to 3 for bolts (but with restrictions: far from edges, min. bolt spacing, min. thickness/bolt d). Values derived from tests are
recommended.
d
The factor gives 0,75 for  ≥ 7%, and 0,375 for  =1% and linear interpolation in between. Values of  are given in Table B.2.
R R R

Table 3 — Value of k stress factor according to load case
L
C
Value of
Load
Keels and appendages — Load case description Subclause
k
case
LC
a
Keel bolt 7.2 0,67
1 Other elements of fixed keel — metal — 0,8
b
Other elements of fixed keel — FRP — 0,9
Canting keel — metal 7.3 0,8
2
Canting keel — FRP — 0,9
3 Keel vertical pounding 7.4 1
4 Keelboat longitudinal impact 7.5 1
5 Dinghy capsize recovery (strength of centre/dagger board) 7.6 1,34
6 Centre/dagger board upwind 7.7 1,0
a
Load case 1 treats bolts differently from other structural materials components. The design stress of bolts is lower than that of other
structural components so as to recognize stress concentration effects in bolts and accord with long-standing design practice.
b
The requirements of this part of ISO 12215 are strength-criteria based. In some cases, such as keel fins constructed of lower
modulus materials, the need to limit deflections and/or increase natural frequencies may require a substantial increase in scantlings
above those requirements. Such cases are outside the scope of this part of ISO 12215.

© ISO 2012 – All rights reserved 5

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SIST EN ISO 12215-9:2012
ISO 12215-9:2012(E)
6 Structural components to be assessed
CAUTION — Keel loss has been found on several occasions to be attributable to insufficient thickness
of bottom plating in respect of the keel, in particularly, connecting bolts or inadequate load paths
between connecting bolts and the corresponding structure, including bolts located too far from the
relevant stiffener. It is strongly recommended that the provisions of D.5 and Table D.2 be followed and,
in particular, for bolts located too far from a stiffener, those of Table D.2, item 3.
The following shall be considered when assessing or designing the structure covered by this part of
ISO 12215.
 Keel-to-hull connection (bolts, wedge connection, stub keel, etc.) — see Figures 1, C.3, C.4 and D.1.
 Bottom shell plating in respect of the keel bolts and transition arrangements beyond the keel bolt zone
into the hull structure: in the case of bolted keels on a hull bottom of sandwich construction, the general
practice outlined in Annex D is to have a single skin construction for keel and bolts. If this is not the case,
the structural arrangement shall ensure that all loads — keel compression loads, bolt preload, etc. — are
safely transferred, using proper core material, inserts, etc. The risk of water permeating the sandwich
core via the bolt holes shall be seriously considered.
 Backing plates/washers, where relevant.
 Floors, girders and associated supporting structure.
 Keel boxes.
 Fins, foils, centreboards, dagger boards.
Wherever possible, assessment should be conducted by numerical methods in accordance with Clause 8.
Alternatively the “established practice” methods given Clause 9 shall be used.
Where calculation procedures do not exist, assessment should be conducted by a combination of
semi-empirical methods and the established practice given in Clause 9.
7 Load cases
7.1 General
7.1.1 Status of design load cases
CAUTION — For load cases 1 and 2 (see references in the list below ) — where keels have a large rake
angle, the centre of gravity (CG) of the bulb/fin can be located a significant distance aft or forward of
the fin or bolt gro
...