SIST EN 13001-2:2005
(Main)Cranes - General design - Part 2: Load actions
Cranes - General design - Part 2: Load actions
This document specifies general conditions, requirements and methods to prevent mechanical hazards of cranes by design and theoretical verification. Note: Specific requirements for particular types of crane are given in the appropriate European Standard for the particular crane type. The following is a list of significant hazardous situations and hazardous events that could result in risks to persons during normal use and foreseeable misuse. Clause 4 of this standard is necessary to reduce or eliminate the risks associated with those hazards: a) rigid body instability of the crane or its parts.
Krane - Konstruktion allgemein - Teil 2: Lasteinwirkungen
Diese Europäische Norm ist zusammen mit Teil 1 und Teil 3 anzuwenden und spezifiziert allgemeine Bedingungen, Anforderungen und Methoden zur Vermeidung von Gefahren bei Kranen durch die Konstruktion und theoretische Überprüfung. Teil 3 befindet sich in der Vorentwurfsphase; die Verwendung der Teile 1 und 2 setzt nicht die Veröffentlichung von Teil 3 voraus.
ANMERKUNG Besondere Anforderungen für spezielle Krantypen sind in der zugehörigen Europäischen Norm für den speziellen Krantyp angegeben.
Im Folgenden ist eine Auflistung von wichtigen gefährlichen Situationen und gefährlichen Ereignissen gegeben, die Risiken für Personen während des normalen Gebrauchs (des Krans) und vorhersehbarem Missbrauch zur Folge haben könnten. Abschnitt 4 dieser Norm wird zur Reduzierung oder Eliminierung der mit den folgenden Gefahrensituationen verbundenen Risiken benötigt:
a) Starrkörperinstabilität des Krans oder seiner Teile;
b) Überschreitung der Festigkeitsgrenzwerte (Fließen, Bruch, Ermüdung);
c) Überschreitung von Temperaturgrenzwerten des Werkstoffs oder der Komponenten;
d) elastische Instabilität des Krans oder seiner Teile;
e) Überschreitung der Verformungsgrenzwerte.
Diese Europäische Norm ist anwendbar für Krane, die nach dem Datum der Genehmigung dieser Norm durch CEN hergestellt werden, und dient als Referenzgrundlage für die Europäischen Normen für spezielle Krantypen.
Appareils de levage a charge suspendue - Conception générale - Partie 2: Effets de charge
La présente norme européenne spécifie les conditions, prescriptions et méthodes générales afin d'éviter les risques mécaniques dus aux grues, en utilisant la conception et la vérification théorique. Note: les prescriptions spécifiques relatives aux types particuliers de grues sont données dans la norme européenne appropriée pour le type particulier de grue. La liste suivante énumere les situations et les événements dangereux significatifs susceptibles d'entraîner des risques pour les personnes lors d'une utilisation normale et d'une mauvaise utilisation prévisible.
Varnost dvigala (žerjava) – Konstrukcija, splošno – 2. del: Bremenski učinki
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 13001-2:2005
01-marec-2005
9DUQRVWGYLJDOD åHUMDYD ±.RQVWUXNFLMDVSORãQR±GHO %UHPHQVNLXþLQNL
Cranes - General design - Part 2: Load actions
Krane - Konstruktion allgemein - Teil 2: Lasteinwirkungen
Appareils de levage a charge suspendue - Conception générale - Partie 2: Effets de
charge
Ta slovenski standard je istoveten z: EN 13001-2:2004
ICS:
53.020.20 Dvigala Cranes
SIST EN 13001-2:2005 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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EUROPEAN STANDARD
EN 13001-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2004
ICS 53.020.20
English version
Crane safety - General design - Part 2: Load effects
Sécurité des appareils de levage à charge suspendue - Kransicherheit - Konstruktion allgemein - Teil 2:
Conception générale - Partie 2: Effets de charge Lasteinwirkungen
This European Standard was approved by CEN on 2 March 2004.
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 Central Secretariat 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 Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2004 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 13001-2:2004: E
worldwide for CEN national Members.
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EN 13001-2:2004 (E)
Contents Page
Foreword . 3
Introduction . 4
1 Scope. 4
2 Normative references. 4
3 Terms, definitions, symbols and abbreviations. 5
3.1 Terms and definitions . 5
3.2 Symbols and abbreviations . 5
4 Safety requirements and/or measures . 9
4.1 General . 9
4.2 Loads. 9
4.2.1 General . 9
4.2.2 Regular loads.10
4.2.3 Occasional loads .16
4.2.4 Exceptional loads .21
4.2.5 Loads on means provided for access .27
4.3 Load combinations.27
4.3.1 General .27
4.3.2 High risk applications .27
4.3.3 Mass distribution classes MDC1 and MDC2.28
4.3.4 Partial safety factors for the mass of the crane .28
4.3.5 Partial safety factors to be applied to loads caused by displacements.29
4.3.6 Survey of load combinations.29
4.3.7 Partial safety factors for the proof of rigid body stability.33
Annex A (normative) Aerodynamic coefficients.36
A.1 General .36
A.2 Individual members .39
A.3 Plane and spatial lattice structure members.43
A.4 Structural members in multiple arrangement.46
Annex B (informative) Selection of a suitable set of crane standards for a given
application .48
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 98/37/EC .49
Bibliography .50
2
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EN 13001-2:2004 (E)
Foreword
This document (EN 13001-2:2004) has been prepared by Technical Committee CEN/TC 147
“Cranes — Safety”, the secretariat of which is held by BSI.
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 June 2005, and conflicting national
standards shall be withdrawn at the latest by June 2005 .
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Czech
Republic, Cyprus, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland,
Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and the United Kingdom.
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 EC Directive 98/37.
For relationship with EC Directives, see informative annex ZA, which is an integral part of this
document.
Annex A is normative, annex B is informative.
This European Standard is one Part of EN 13001. The other parts are as follows:
Part 1: General principles and requirements
Part 2: Load actions
Part 3.1: Limit states and proof of competence of steel structures
Part 3.2: Limit states and proof of competence of rope reeving components
Part 3.3: Limit states and proof of competence of wheel/rail contacts
Part 3.4: Limit states and proof of competence of machinery
3
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EN 13001-2:2004 (E)
Introduction
This European Standard has been prepared to be a harmonised standard to provide one means for
the mechanical design and theoretical verification of cranes to conform with the essential health and
safety requirements of the Machinery Directive, as amended. This standard also establishes
interfaces between the user (purchaser) and the designer, as well as between the designer and the
component manufacturer, in order to form a basis for selecting cranes and components.
This European Standard is a type C standard as stated in the EN 1070.
The machinery concerned and the extent to which hazards are covered are indicated in the scope of
this standard.
When provisions of this type C standard are different from those, which are stated in type A or B
standards, the provisions of this type C standard take precedence over the provisions of the other
standards, for machines that have been designed and built according to the provisions of this type C
standard.
1 Scope
This European Standard is to be used together with Part 1 and Part 3 and as such they specify
general conditions, requirements and methods to prevent hazards of cranes by design and theoretical
verification. Part 3 is only at pre-drafting stage; the use of Parts 1 and 2 is not conditional to the
publication of Part 3.
NOTE Specific requirements for particular types of crane are given in the appropriate European Standard
for the particular crane type.
The following is a list of significant hazardous situations and hazardous events that could result in
risks to persons during normal use and foreseeable misuse. Clause 4 of this standard is necessary to
reduce or eliminate the risks associated with the following hazards:
a) Rigid body instability of the crane or its parts (tilting and shifting).
b) Exceeding the limits of strength (yield, ultimate, fatigue).
c) Elastic instability of the crane or its parts (buckling, bulging).
d) Exceeding temperature limits of material or components.
e) Exceeding the deformation limits.
This European Standard is applicable to cranes which are manufactured after the date of approval by
CEN of this standard and serves as reference base for the European Standards for particular crane
types.
2 Normative references
This European Standard incorporates, by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to, or revisions of
any of these publications apply to this European Standard only when incorporated in it by amendment
4
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EN 13001-2:2004 (E)
or revision. For undated references the latest editions of the publication referred to applies (including
amendments).
EN ISO 12100-1:2003, Safety of machinery — Basic concepts, general principles for design — Part 1:
Basic terminology, methodology (ISO 12100-1:2003).
EN ISO 12100-2:2003, Safety of machinery — Basic concepts, general principles for design — Part 2:
Technical principles and specifications (ISO 12100-2:2003).
EN 1070: 1998, Safety of machinery — Terminology.
EN 1990-1:2002, Eurocode – Basic of structural design.
EN 13001-1, Cranes — General Design — Part 1: General principles and requirements.
ISO 4306-1: 1990, Cranes — Vocabulary — Part 1: General.
3 Terms, definitions, symbols and abbreviations
3.1 Terms and definitions
For the purposes of this European Standard, the terms and definitions given in EN 1070:1998,
ENV 1990-1:2002 and clause 6 of ISO 4306-1:1990 apply.
3.2 Symbols and abbreviations
For the purposes of this European Standard, the symbols and abbreviations given in Table 1 apply.
Table 1 — Symbols and abbreviations
Symbols,
Description
abbreviations
A1 to A4 Load combinations including regular loads
A Characteristic area of a crane member
A Projection of the gross load on a plane normal to the direction of the wind
g
velocity
Area enclosed by the boundary of a lattice work member in the plane of its
A
c
characteristic height d
A Area of an individual crane member projected to the plane of the
j
characteristic height d
b Width of the rail head
h
b Characteristic width of a crane member
B1 to B5 Load combinations including regular and occasional loads
c Spring constant
c , c , c Aerodynamic coefficients
a oy oz
c Aerodynamic coefficient of a member of infinite length
o
C1 to C9 Load combinations including regular, occasional and exceptional loads
CFF, CFM Coupled wheel pairs of system F/F or F/M
d Characteristic dimension of a crane member
5
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EN 13001-2:2004 (E)
Table 1 (continued)
Symbols,
Description
abbreviations
d, d Distance between wheel pair i or n and the guide means
i n
e Width of the gap of a rail
G
f Friction coefficient
f Loads
i
f natural frequency
q
f Term used in calculating v(z)
rec
F Force
F, F , F Wind loads
y z
F Buffer force
b
ˆ
Maximum buffer force
F
F F Initial and final drive force
i, f
DF Change of drive force
F , F
x1i x2i
Tangential wheel forces
F , F
y1i y2i
F Guide force
y
F , F Vertical wheel forces
z1i z2i
Abbreviations for Fixed/Fixed and Fixed/Moveable, characterizing the
F/F, F/M
possibility of lateral movements of the crane wheels
g Gravity constant
Distance between instantaneous slide pole and guide means of a skewing
h
crane
h(t) Time-dependent unevenness function
h Height of the step of a rail
s
Lateral wheel forces induced by drive forces acting on a crane or trolley with
H1, H2
asymmetrical mass distribution
HC1 to HC4 Hoisting classes
HD1 to HD5 Classes of the type of hoist drive and its operation method
i Serial number
IFF, IFM Independent wheel pairs of system F/F or F/M
j Serial number
k Serial number
K Drag-coefficient of terrain
K1, K2 Roughness factors
l Span of a crane
l Aerodynamic length of a crane member
a
l Geometric length of a crane member
o
m Mass of the gross or hoist load
H
6
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EN 13001-2:2004 (E)
Table 1 (continued)
Symbols,
Description
abbreviations
m Mass of the crane and the hoist load
Released or dropped part of the hoist load
Dm
H
MDC1, MDC2 Mass distribution classes
n Number of wheels at each side of the crane runway
n
Exponent used in calculating g
r
n
n
Exponent used in calculating the shielding factor h
m
p Number of pairs of coupled wheels
q Equivalent static wind pressure
q
Mean wind pressure
q(z) Equivalent static storm wind pressure
q(3) Wind pressure at v (3)
r Wheel radius
R Stormwind recurrence interval
Re Reynold number
s Slack of the guide
g
s Lateral slip at the guide means
y
s Lateral slip at wheel pair i
yi
S Load effect
ˆ
Maximum load effect
S
S1, S2 Stability classes
S, S Initial and final load effects
i f
Change of load effect
DS
t Time
u Buffer stroke
û Maximum buffer stroke
v Travelling speed of the crane
Constant mean wind velocity
v
Constant mean wind velocity if the wind direction is not normal to the
v *
longitudinal axis of the crane member under consideration
v(z) Equivalent static storm wind velocity
Equivalent static storm wind velocity if the wind direction is not normal to the
v(z)*
longitudinal axis of the crane member under consideration
v(3) Gust wind velocity averaged of a period of 3 seconds
v Three seconds gust amplitude
g
v Hoisting speed
h
v Maximum steady hoisting speed
h,max
v Steady hoisting creep speed
h,CS
7
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EN 13001-2:2004 (E)
Table 1 (continued)
Symbols,
Description
abbreviations
v (z) Ten minutes mean storm wind velocity in the height z
m
v Reference storm wind velocity
ref
w Distance between the guide means
b
z Height above ground level
z(t) Time-dependent coordinate of the mass centre
Relative aerodynamic length
a
r
Angle between the direction of the wind velocity v or v(z) and the
a
w
longitudinal axis of the crane member under consideration
a Skewing angle
a Part of the skewing angle a due to the slack of the guide
g
a Term used in calculating f
G 4
a Term used in calculating f
s 4
a Part of the skewing angle a due to tolerances
t
a Part of the skewing angle a due to wear
w
Angle between horizontal plane and non-horizontal wind direction
b
b Term used in calculating f
2 2
b Term used in calculating f
3 3
Overall safety factor
g
f
Resistance coefficient
g
m
Risk coefficient
g
n
g Partial safety factor
p
d Term used in calculating f
1
Conventional start force factor
e
S
Conventional mean drive force factor
e
M
Shielding factor
h
Factor for remaining hoist load in out of service condition
h
W
Aerodynamic slenderness ratio
l
m, m¢ Parts of the span l
F Term used in calculating the guide force F
y
F , F Terms used in calculating F and F
1i 2i y1i y2i
x Term used in calculating f
7
Term used in calculating F and F
x , x
1i 2i x1i x2i
Curve factors
x (a ), x (a )
G G s s
r Density of the air
j Solidity ratio
Dynamic factors
f
i
8
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EN 13001-2:2004 (E)
Table 1 (concluded)
Symbols,
Description
abbreviations
Dynamic factor for hoisting and gravity effects acting on the mass of the
f
1
crane
Dynamic factor for inertial and gravity effects by hoisting an
f
2
unrestrained grounded load
f Term used in calculating f
2min 2
Dynamic factor for inertial and gravity effects by sudden release of a part of
f
3
the hoist load
Dynamic factor for loads caused by travelling on uneven surface
f
4
f Dynamic factor for loads caused by acceleration of all crane drives
5
f Dynamic factor for test loads
6
Dynamic factor for loads due to buffer forces
f
7
Gust response factor
f
8
Reduction factor used in calculating aerodynamic coefficients
y
4 Safety requirements and/or measures
4.1 General
Machinery shall conform to the safety requirements and/or measures of this clause. In addition, the
machine shall be designed according to the principles of EN ISO 12100-1:2003 and
EN ISO 12100-2:2003 for hazards relevant but not significant which are not dealt with by this
document (e. g. sharp edges).
4.2 Loads
4.2.1 General
4.2.1.1 Introduction
The loads acting on a crane are divided into the categories of regular, occasional and exceptional as
given in 4.2.1.2, 4.2.1.3 and 4.2.1.4. For the proof calculation of means of access loads only acting
locally are given in 4.1.5.
These loads shall be considered in proof against failure by uncontrolled movement, yielding, elastic
instability and, where applicable, against fatigue.
4.2.1.2 Regular loads
a) hoisting and gravity effects acting on the mass of the crane;
b) inertial and gravity effects acting vertically on the hoist load;
c) loads caused by travelling on uneven surface;
d) loads caused by acceleration of all crane drives;
e) loads induced by displacements.
9
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EN 13001-2:2004 (E)
Regular loads occur frequently under normal operation.
4.2.1.3 Occasional loads
a) loads due to in-service wind;
b) snow and ice loads;
c) loads due to temperature variation;
d) loads caused by skewing.
NOTE Occasional loads occur infrequently. They are usually neglected in fatigue assessment.
4.2.1.4 Exceptional loads
a) loads caused by hoisting a grounded load under exceptional circumstances;
b) loads due to out-of-service wind;
c) test loads;
d) loads due to buffer forces;
e) loads due to tilting forces;
f) loads caused by emergency cut-out;
g) loads caused by failure of mechanism or components;
h) loads due to external excitation of crane foundation;
i) loads caused by erection and dismantling.
NOTE Exceptional loads are also infrequent and are likewise usually excluded from fatigue assessment.
4.2.2 Regular loads
4.2.2.1 Hoisting and gravity effects acting on the mass of the crane
When lifting the load off the ground or when releasing the load or parts of the load vibrational
excitation of the crane structure shall be taken into account. The gravitational force induced by the
mass of the crane or crane parts shall be multiplied by the factor f The masses of cranes or crane
1.
parts in class MDC1 (see 4.3.3) shall be multiplied by
f = 1+ d , 0 £ d £ 0,1 (1)
1
The value of d depends on the crane structure and shall be specified.
The divisions of masses of crane parts in class MDC2 (see 4.3.3) shall be multiplied by
f = 1± d , (2)
1
depending whether their gravitational acting is partly increasing (+d) or decreasing (-d) the resulting
load effects in the critical points selected for the proof calculation.
The mass of the crane includes those components, which are always in place during operation except
for the net load itself. For some cranes or applications, it may be necessary to add mass to account
for accumulation of debris.
10
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EN 13001-2:2004 (E)
4.2.2.2 Inertial and gravity effects acting vertically on the hoist load
4.2.2.2.1 Hoisting an unrestrained grounded load
In the case of hoisting an unrestrained grounded load, the hereby induced vibrational effects shall be
taken into account by multiplying the gravitational force due to the mass of the hoist load by a factor
f (see Figure 1).
2
The mass of the hoist load includes the masses of the payload, lifting attachments and a portion of
the suspended hoist ropes or chains etc.
Figure 1 — Factor f2
The factor f shall be taken as follows:
2
f = f + ß v (3)
2 2,min 2 h
f and b are given in Table 2 for the appropriate hoisting class. For the purposes of this standard,
2,min 2
cranes are assigned to hoisting classes ranging from HC1 to HC4 according to their dynamic and
elastic characteristics. HC1 requires a flexible structure and a drive system with smooth dynamic
characteristics, whereas a rigid structure and a drive system with sudden speed changes imply HC4.
The selection of hoisting classes depends on the particular type of cranes and is dealt with in the
European Standards for specific crane types, see annex B. Equally, values of f can be determined
2
by experiments or analysis without reference to hoisting class.
v is the steady hoisting speed, in meters per second, related to the lifting attachment. Values of v
h h
are given in Table 3.
Table 2 — Values of b and f ,min
2 2
Hoisting class of appliance b f
2 2,min
HC1 0,17 1,05
HC2 0,34 1,10
HC3 0,51 1,15
HC4 0,68 1,20
11
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EN 13001-2:2004 (E)
Table 3 — Values of v for estimation of f
h 2
Load combination Type of hoist drive and its operation method
(see 4.3.6)
HD1 HD2 HD3 HD4 HD5
A1, B1 v v v v = 0
0,5 × v
h,max h,CS h,CS h
h,max
C1 – v – v 0,5 × v
h,max h,max h,max
Where:
HD1: hoist drive cannot be operated with creep speed;
HD2: a steady creep speed of the hoist drive can be selected by the crane driver;
HD3: hoist drive control ensures a steady creep speed until the load is lifted from the ground;
HD4: a stepless variable speed control can be operated by the crane driver;
HD5: after prestressing the hoist medium, the hoist drive control provides the reaching of a
selected speed with an acceleration independent of the crane driver;
v is the maximum steady hoisting speed;
h,max
v is the steady hoisting creep speed.
h,CS
4.2.2.2.2 Sudden release of a part of the hoist load
For cranes that release a part of the hoist load as a normal working procedure, the peak dynamic
action on the crane can be taken into account by multiplying the hoist load by the factor f (see
3
Figure 2).
Figure 2 — Factor f
3
The factor f shall be taken as follows:
3
Dm
H
f = 1- (1+ ß ) (4)
3 3
m
H
where:
Dm is the released part of the hoist load;
H
12
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EN 13001-2:2004 (E)
m is the mass of the hoist load;
H
b = 0,5 for cranes equipped with grabs or similar slow-release devices;
3
b = 1,0 for cranes equipped with magnets or similar rapid-release devices.
3
4.2.2.3 Loads caused by travelling on uneven surface
The dynamic actions on the crane by travelling, with or without load, on or off roadways or on rail
tracks shall be estimated, by experiment or by calculation using an appropriate model for the crane or
the trolley and the travel surface or the track, and shall be specified.
When calculating the dynamic actions on the crane by travelling, the induced accelerations shall be
taken into account by multiplying the gravitational forces due to the masses of the crane and hoist
load by a factor f .
4
European Standards for specific crane types specify tolerances for rail tracks and ground conditions
and give conventional values for f .
4
Where there is no specific factor f , it may be estimated by using a simple single mass - spring -
4
model for the crane as shown in Figure 3.
Key
m mass of the crane and the hoist load;
v constant horizontal travelling speedof the crane;
c spring constant;
z(t) coordinate of the mass centre;
h(t) unevenness function describing the step or gap of the rail;
Figure 3 — Single mass model of a crane for determining the factor f
4
f may be calculated as follows:
4
2
2
p v
æ ö
f = 1+ ç ÷ x (5) for travelling over a step (see Figure 4a);
4 s
2 g r
è ø
2
2
p v
æ ö
f = 1+ x (6) for travelling over a gap (see Figure 4b);
ç ÷
4 G
2 g r
è ø
where:
v is the constant horizontal travelling speed of the crane;
r is the wheel radius;
2
g = 9,81 m/s is the gravity constant;
13
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EN 13001-2:2004 (E)
x (a ), x (a ) are curve factors that become maximum for the time period after the wheel has
s s G G
passed the unevenness; they can be determined for a < 1,3 and a < 1,3 by the
s G
diagrams given in Figure 5;
where:
2 f h
2r
q s
(see Figure 5a);
a =
s
v h
s
f e
q G
a = (see Figure 5b);
G
v
h is the height of the step (see Figure 4);
s
e is the width of the gap (see Figure 4);
G
c/ m
f = is the natural frequency of a single mass model of the crane (see
q
2p
Figure 3). If unknown, to be taken as 10 Hz.
a) Travelling over a step b) Travelling over a gap
Figure 4 — Movement of the wheel centre
a) Travelling over a step b) Travelling over a gap
Figure 5 — Curve factors x (a ) and x (a )
s s G G
NOTE The use of this simple model is restricted to cranes whose actual dynamic behaviour corresponds to
that of the model. If more than one natural mode contributes a significant response and/or rotation occurs, the
designer should estimate the dynamic loads using an appropriate model for the circumstances.
14
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EN 13001-2:2004 (E)
4.2.2.4 Loads caused by acceleration of drives
Loads induced in a crane by acceleration or decelerations caused by drive forces may be calculated
using rigid body kinetic models. For this purpose, the gross load is taken to be fixed at the top of the
jib or immediately below the crab.
ˆ
The load effect S shall be applied to the components exposed to the drive forces and where
applicable to the crane and the gross load as well. As a rigid body analysis does not directly reflect
ˆ
elastic effects, the load effect S shall be calculated by using a factor f as follows (see Figure 6):
5
ˆ
S = S + f DS (7)
i 5
where:
DS=S -S is the change of the load effect due to the change of the drive force DF = F - F;
f i f i
S, S are the initial (i) and final (f) load effects caused by F and F ;
i f i f
F, F are the initial (i) and final (f) drive forces.
i f
a) for the change of drive forces from steady
b) for the positioning case
state
Figure 6 — Factor f
5
Following values of f shall be applied:
5
f = 1 for centrifugal forces;
5
1 £ f £ 1,5 for drives with no backlash or in cases where existing backlash does not affect the
5
dynamic forces and with smooth change of forces;
1,5 £ f £ 2 for drives with no backlash or in cases where existing backlash does not affect the
5
dynamic forces and with sudden change of forces;
f = 3 for drives with considerable backlash, if not estimated more accurate by using a
5
spring-mass-model.
Where a force that can be transmitted is limited by friction or by the nature of the drive mechanism,
the limited force and a factor f appropriate to that system shall be used.
5
4.2.2.5 Loads induced by displacements
Account shall be taken of loads arising from displacements included in the design such as those
within the limits necessary to initiate response from compensating systems (e.g. skewing) or those
resulting from prestressing.
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EN 13001-2:2004 (E)
Other loads to be considered include those that can arise from displacements that are within defined
limits such as those set for the variations in the height or the gauge between rails or uneven
settlement of supports.
4.2.3 Occasional loads
4.2.3.1 Loads due to in-service wind
The wind loads assumed to act perpendicularly to the longitudinal axis of a crane member are
calculated by
= (3)´ ´ (8) regarding the structure of the crane;
F q c A
F = e ´ q(3)´ c ´ A (9) regarding the required starting drive forces;
S
F = e ´ q(3) ´ c ´ A (10) regarding the drive forces during controlled movement;
M
where:
F is the wind load acting perpendicularly to the longitudinal axis of the member under
consideration;
c is the aerodynamic coefficient of the member under consideration; it shall be used in
combination with the characteristic area A; values of c shall be as given in annex A;
A is the ch
...
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