Load restraint assemblies on road vehicles - Safety - Part 1: Calculation of securing forces

This Part of prEN 12195 specifies acceleration coefficients for surface transport. It also gives methods of calculation of lashing forces acting on goods on load carriers, lorries, trailers and swap bodies, either on road, on vessels or by rail and/or combinations thereof for different types of load and different types of lashing. It  excludes the hump shunting during railway transport (web lashings see EN 12195-2, lashing chains see EN 12195-3, wire lashing ropes see prEN 12195-4).
The lashing forces to be chosen for calculation in this EN 12195-1 are static forces produced by tensioning of lashings and dynamic forces, which act on the lashing as a reaction of the load movements.
Instructions for the application of calculations are also specified.

Ladungssicherungseinrichtungen auf Straßenfahrzeugen - Sicherheit - Teil 1: Berechnung von Sicherungskräften

Dieser Teil von EN 12195 bezieht sich auf die Auslegung der verschiedenen Sicherungsverfahren (Blockieren, Zurren und deren Kombinationen) zur Ladungssicherung für den Land- und Seetransport durch Straßenfahrzeuge oder Teilen davon (LKW, Anhänger, Container und Wechselbehälter), einschließlich ihres Transportes auf Schiffen oder auf der Schiene und/oder einer Kombination dieser Verkehrsarten. Der Ablaufrangierbetrieb ist ausgeschlossen (Zurrgurte siehe EN 12195-2, Zurrketten siehe EN 12195 3, Zurrdrahtseile siehe EN 12195-4).
Diese Norm gilt nicht für Fahrzeuge mit einem Gesamtgewicht von weniger als 3,5 t.
ANMERKUNG   Leichtere Fahrzeuge können über Bremssysteme verfügen, die zu höheren Beschleunigungswerten auf der Straße   führen.
Für die Bemessung der Ladungssicherung wird zwischen stabilen und kippgefährdeten Ladungen unterschieden.
Außerdem werden die Beschleunigungsbeiwerte für den Land- und Seetransport festgelegt.
Beim Niederzurren wird der Kraftverlust der Spannkraft im Zurrmittel an den Außenkanten zwischen Ladung und Zurrmittel berücksichtigt. Die für die Berechnung in dieser EN 12195-1 gewählten Sicherungskräfte sind statische Kräfte, die durch das Spannen der Zurrmittel entstehen, sowie dynamische Kräfte, die auf das Zurrmittel als Rückwirkung der Ladungsbewegungen wirken.
Beispiele für die Anwendung der Berechnungen sind in den Anhängen angegeben.

Dispositifs d'arrimage des charges à bord des véhicules routiers - Sécurité - Partie 1: Calcul des forces de retenue

La présente partie de l’EN 12195 concerne la conception des méthodes d’immobilisation (blocage, arrimage et combinaisons) pour l’immobilisation des charges dans le cadre du transport de surface par véhicules routiers ou parties de ces derniers (camions, remorques, conteneurs, carrosseries mobiles), que ce soit sur route, à bord de navires ou par chemin de fer et/ou avec des combinaisons de ces divers modes de transport. Elle ne traite pas de la manœuvre par gravité lors du transport ferroviaire (sangles d'arrimage, voir EN 12195 2, chaînes d'arrimage, voir EN 12195-3, câbles d'arrimage en acier, voir EN 12195-4).
La présente norme ne s’applique pas aux véhicules d’un poids total inférieur à 3,5 t.
NOTE   Les véhicules plus légers peuvent avoir des systèmes de freinage qui fournissent des valeurs d’accélération plus élevées sur route.
Pour le dimensionnement de l’immobilisation de la charge, une distinction est faite entre les charges stationnaires et les charges susceptibles d’inclinaison.
Par ailleurs, les coefficients d’accélération pour le transport de surface sont spécifiés.
Pour l’arrimage par le dessus, la diminution de la tension de l’arrimage au niveau des bords extérieurs entre la charge et l’arrimage est prise en considération. Les forces d'arrimage de retenue à choisir pour effectuer les calculs selon la présente norme EN 12195-1 sont les forces statiques générées par le blocage ou la tension des dispositifs d’arrimages et les forces dynamiques, qui agissent sur les arrimages en réaction aux mouvements des charges.
Des exemples pour l’application de ces calculs sont donnés dans les Annexes.

Naprave za varovanje tovora na cestnih vozilih - Varnost - 1. del: Izračun sil za zavarovanje tovora

General Information

Status
Not Published
Public Enquiry End Date
24-Apr-2008
Current Stage
98 - Abandoned project (Adopted Project)
Start Date
19-Aug-2010
Due Date
24-Aug-2010
Completion Date
19-Aug-2010

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SLOVENSKI STANDARD
oSIST prEN 12195-1:2008
01-april-2008
1DSUDYH]DYDURYDQMHWRYRUDQDFHVWQLKYR]LOLK9DUQRVWGHO,]UDþXQVLO]D
]DYDURYDQMHWRYRUD
Load restraint assemblies on road vehicles - Safety - Part 1: Calculation of securing
forces
Ladungssicherungseinrichtungen auf Straßenfahrzeugen - Sicherheit - Teil 1:
Berechnung von Sicherungskräften
Dispositifs d'arrimage des charges à bord des véhicules routiers - Sécurité - Partie 1:
Calcul des forces de retenue
Ta slovenski standard je istoveten z: prEN 12195-1
ICS:
53.080
55.180.99
oSIST prEN 12195-1:2008 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
EUROPEAN STANDARD
DRAFT
prEN 12195-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2008
ICS 55.180.99; 53.080 Will supersede EN 12195-1:2003
English Version
Load restraint assemblies on road vehicles - Safety - Part 1:
Calculation of securing forces
Dispositifs d'arrimage des charges à bord des véhicules Ladungssicherungseinrichtungen auf Straßenfahrzeugen -
routiers - Sécurité - Partie 1: Calcul des forces de retenue Sicherheit - Teil 1: Berechnung von Sicherungskräften
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 168.
If this draft becomes a European Standard, 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.
This draft European Standard was established by CEN 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 Management Centre has the
same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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 and United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12195-1:2008: E
worldwide for CEN national Members.

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prEN 12195-1:2008 (E)
Contents
page
Foreword.3
Introduction .4
1 Scope .4
2 Normative references .4
3 Terms, definitions, symbols, units and abbreviations.5
3.1 General terms and definitions.5
3.2 Definition of calculation parameters.6
3.3 Symbols, units and terms .8
4 Acceleration coefficients .9
4.1 General.9
4.2 Load on load carriers during road transport .9
4.3 Load on load carriers during rail transport.10
4.4 Load on load carriers during sea transport .10
5 Methods of calculation.11
5.1 General.11
5.2 Stability of unsecured load.11
5.3 Blocking.12
5.4 Frictional lashing .13
5.4.1 General.13
5.4.2 Avoiding sliding.14
5.4.3 Avoiding tilting.16
5.5 Direct lashing .18
5.5.1 General.18
5.5.2 Slope lashing in longitudinal or transverse direction.19
5.5.3 Diagonal lashing .20
5.5.4 Loop lashing.25
6 Parameters .26
6.1 Friction factor.26
6.2 Transmission of force during frictional lashing.26
7 Cargo securing testing.26
8 Instruction for use .27
8.1 Marking .27
Annex A (informative)  Examples for the calculation of lashing forces .28
Annex B (informative)  Estimated friction factors of some usual goods µµ .49
µµ
Annex C (informative) Load securing docket.51
Annex D (informative) Practical inclination test for determination of the efficiency of cargo securing
arrangements .53
Annex E (informative) Documentation of practical tests .56
Annex F (informative) Equations for loop and spring lashing .57
F.1 Loop Lashing .57
F.1.1 Loop lashing to prevent sliding .57
F.1.2 Loop lashing to prevent tilting for one or several cargo rows .58
F.1.3 Spring lashing.60


2

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prEN 12195-1:2008 (E)
Foreword
This document (prEN 12195-1:2008) has been prepared by Technical Committee CEN/TC 168 “Chains, ropes,
webbing, slings and accessories - Safety”, the secretariat of which is held by BSI.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12195-1:2003.
EN 12195 consists of the following parts under the general title “Load restraint assemblies on road vehicles –
Safety”:
Part 1: Calculation of securing forces
Part 2: Web lashing made from man-made fibres
Part 3: Lashing chains
Part 4: Lashing steel wire ropes
Annex A to Annex F are informative.

3

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prEN 12195-1:2008 (E)
Introduction
This Part of EN 12195 has been prepared to provide one means of conforming with the essential safety require-
ments to calculate securing forces for load restraint assemblies to be used in the Common European Market and
thus enabling the free movement of goods.
This Part of EN 12195 contributes to the harmonization of the calculation of load securing on road vehicles by de-
fining the different procedures and equations of load securing.
Blocking and lashing procedures and appropriate combinations are described for load securing. The equations
used are based on relevant scientific and, in particular, on mechanical laws and practical experience. For this pur-
pose, a suitable vehicle with appropriate assemblies for blocking, bracing and securing is to be used to ensure safe
load transportation. Transportation safety should be guaranteed by the dimensioning of load securing according to
this Standard. The extent to which the hazards acting on the load during transport and resulting from the forces of
load are addressed is given in the scope of this standard. In addition, load restraint assemblies for securing of
loads on vehicles with respect to their securing and load bearing ability, which are not covered by this standard,
should conform to the other parts of this standard and to EN ISO 12100 Part 2.
1 Scope
This Part of EN 12195 refers to the design of securing methods (blocking, lashing, and combinations) for securing
of loads for surface transport by road vehicles or parts of them (lorries, trailers, containers and swap bodies), in-
cluding their transport on vessels or by rail and/or combinations thereof. Hump shunting during railway transport is
excluded. (Web lashings see EN 12195-2, lashing chains see EN 12195-3, lashing steel wire ropes see EN
12195-4).
This standard does not apply for vehicles with a total weight lower than 3,5 t.
Note: Lighter vehicles may have braking systems, which give higher values of acceleration on the road.
For dimensioning of load securing a distinction is made between steady loads and loads liable to tilting.
Furthermore, the acceleration coefficients for surface transport are specified.
For over top lashing the force loss in the tension force of the lashing at the outer edges between load and lashing is
taken into account. The securing forces to be chosen for calculation in this EN 12195-1 are static forces produced
by blocking or tensioning of lashings and dynamic forces, which act on the lashing as a reaction of the load move-
ments.
Examples for the application of calculations are given in the Annexes.
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.
EN ISO 12100-2, Safety of machinery — Basic concepts, general principles for design — Part 2: Technical princi-
ples
EN 12195-2:2000, Load restraint assemblies on road vehicles — Safety — Part 2: Web lashing made from man-
made fibres
EN 12195-3, Load restraint assemblies on road vehicles — Safety — Part 3: Lashing chains
4

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prEN 12195-1:2008 (E)
EN 12195-4, Load restraint assemblies on road vehicles — Safety — Part 4: Lashing steel wire ropes
EN 12640, Securing of cargo on road vehicles — Lashing points on commercial vehicles for goods transportation -
Minimum requirements and testing
EN 12642:2006, Securing of cargo on road vehicles — Body structure of commercial vehicles — Minimum re-
quirements
EN 1492-1, Textile slings — Safety — Part 1: Flat woven webbing slings, made of man-made fibres, for general
purpose use
EN 1492-2, Textile slings — Safety — Part 2: Roundslings, made of man-made fibres, for general purpose use
3 Terms, definitions, symbols, units and abbreviations
For the purposes of this draft European Standard, the following terms, definitions, symbols, units and abbreviations
apply.
3.1 General terms and definitions
3.1.1
load restraint assembly
systems and devices for the securing of loads
[EN 12195-2:2000]
3.1.2
lashing
securing method where bendable devices are used in the securing of the load on a load carrier
3.1.3
tensioning device
mechanical device inducing and maintaining a tensile force in a load restraint assembly (e. g. ratchets, winches,
overcentre buckles)
[EN 12195-2:2000]
3.1.4
tension force indicator
device which indicates the force applied to the lashing system by means of the tension devices and movement of
the load or elastic deformation of the vehicle body, acting on the lashing equipment
[EN 12195-2:2000]
3.1.5
attachment point
rigid part of the load, e. g. eyebolt, to place the load restraint assembly
3.1.6
lashing point
securing device on a load carrier to which a lashing may be directly attached .A lashing point can be e. g. an oval
link, a hook, a D-ring, a lashing rail
3.1.7
standard tension force
S
TF
residual force after physical release of the handle of the tensioning device
5

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prEN 12195-1:2008 (E)
[EN 12195-3:2001]

3.1.8
frictional lashing method
lashing procedure (e.g. top over) where the friction force is enhanced by adding a vertical force component to the
weight of the load
3.1.9
direct lashing method
lashing procedure where the forces from the load are taken by the lashings to the fixed parts of a load carrier

3.1.10
blocking
securing method where the load lies flush against fixed structures or fixtures on the load carrier, may be in the form
of headboards, sideboards, sidewalls, stanchions, wedges, supporting beams, bracing or other devices.
3.1.11
securing
locking, blocking, lashing or combination of blocking and lashing to secure a load to all directions on the load car-
rier to prevent sliding and tilting
3.1.12
bracing
method of blocking mostly wooden structure, fixed to the load carrier to keep a load in one ore more directions at its
place.
3.1.13
unstable load
load which unsecured will tilt when exposed to the given accelerations
3.1.14
load carrier
device such as a vehicle, trailer, swap body, container etc. carrying load
3.1.15
locking
securing method where the load is secured by mechanical devices e.g. twist-locks on a load carrier
3.2 Definition of calculation parameters
3.2.1
mass of the load
m
mass which is to be secured
3.2.2
acceleration of the load
a
maximum acceleration of the load during a specific type of transportation
3.2.3
acceleration coefficient
c
coefficient which when multiplied by the acceleration due to gravity g gives the acceleration a = c g of the load dur-
ing a specific type of transportation
3.2.4
longitudinal force of the load
F
x
inertia force, which acts on the load as a result of the load carrier movements in its longitudinal axis (x-axis) (Fx = m
cx g)
6

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prEN 12195-1:2008 (E)
3.2.5
transverse force of the load
F
y
inertia force, which acts on the load as a result of the load carrier movements in its transverse axis (y-axis) (Fy = m
cy g)
3.2.6
vertical force of the load
F
z
sum of forces that arise from the weight of the load and the inertia force which acts on the load (F = m c g) due to
z z
the load carrier movements during the transport in the vertical axis (z-axis) of a load carrier
3.2.7
estimated friction factor
µµµµ
friction coefficient to be used in the equations based on practical tests and acting between the load and the adjoin-
ing surface
3.2.8
friction force
F
F
force acting due to the friction between load and adjoining surfaces against the movement of the load
3.2.9
blocking force
F
B
force acting on a blocking device in a specified direction
3.2.10
blocking capacity
BC
maximum force that a blocking device is designed to carry in a specified direction
3.2.11
number
n
number of lashings
3.2.12
tension force of a lashing
F
T
force in the lashing created by tensioning of a tensioning device
3.2.13
restraining force of a lashing
F
R
force carried by a lashing device to prevent movements of a load in relation to a load carrier during transport
3.2.14
lashing capacity
LC
maximum allowed force that a lashing device is designed to sustain in use
3.2.15
vertical lashing angle
αααα
angle between lashing and the horizontal plane
3.2.16
longitudinal lashing angle
ββββ
x
angle between lashing and longitudinal axis (x-axis) of a load carrier in the plane of the loading area
7

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prEN 12195-1:2008 (E)
3.2.17
transverse lashing angle
ββ
ββ
y
angle between lashing and transverse axis (y-axis) of a load carrier in the plane of the loading area
3.2.18
safety factor
f
s
factor to cover uncertainties of distribution of tension forces for frictional lashing
3.3 Symbols, units and terms
Table 1 — Symbols, units and terms
Symbol Unit Term
B m Total width of the load section
BC kN Blocking capacity
F
kN Force
F
kN Blocking force
B

F kN Restraining force of a lashing
R

F kN Tension force of a lashing
T

F
kN Longitudinal force actuated by the load
x

F
kN Transverse force actuated by the load
y

F kN Vertical force actuated by the load
z

F kN Friction force
F

F
kN Friction force as result of the vertical force F
FM z


F Friction force as result of the restraining force F
kN
FR R

F kN Friction force as result of the tension force F
FT T

F kN Maximum force to which a lashing point is designed
LP
H
m Total height of the load section
LC
kN Lashing capacity
S kN Standard tension force
TF

a m/s² Acceleration
b
m Lever arm of the standing moment
c
— Acceleration coefficient
c — Longitudinal acceleration coefficient
x
c — Transverse acceleration coefficient
y
c — Vertical acceleration coefficient
z
d m Lever arm of the tilting moment
f
— Safety factor for frictional lashing
S

g
m/s² Gravitational acceleration

g m/s² Standard acceleration due to gravity g = 9,80665 m/s²
n n

h m Lever arm of the lashing moment
8

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prEN 12195-1:2008 (E)
Symbol Unit Term
i — Index for lashing lines
k — Coefficient of transmission
m t Mass of the load
n
— Number of lashings
N — Number of rows
o — Number of lashings
Horizontal distance from the outer edge of the load to the point
p
m
where the lashing acts on the load
Horizontal distance from the outer edge of the load to the tipping
r m
point
Vertical distance from the platform to the point where the lashing
s m
acts on the load
t m Vertical distance from the platform to the tipping point
w m Width of the load
α ° Vertical lashing angle
° Longitudinal lashing angle
β
x
β ° Transverse lashing angle
y
µ — Estimated friction factor
µ — Internal friction
i
4 Acceleration coefficients
4.1 General
The acceleration coefficients given in the Tables 2, 3 and 4 are specified according to 3.2.2 and 3.2.3 as maximum
values for a load on a vehicle for the specific type of transportation.
Combinations of longitudinal and transverse accelerations occurring during transport, e. g. values below the maxi-
mum values, are covered by the values of the tables.
Superposition of the weight of the load with high frequency stresses and occasional occurring shock loadings of
short duration are absorbed by the elongation of the lashings and the shock absorber system of the lorries and trail-
ers. This occurs without any significant increase of stress, so that this can be ignored for the purpose of this stan-
dard which gives a practical and not a scientific view.
4.2 Load on load carriers during road transport
The acceleration coefficients for load carriers during road transport shall be as given in Table 2.
9

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prEN 12195-1:2008 (E)

Table 2 — Acceleration coefficients c , c and c during road transport
x y z
Acceleration coefficients
Securing in c , longitudinally c , transversely
x y
c , vertically down
z
forward rearward sliding only tilting
longitudinal direction 0,8 0,5 — — 1,0

a
transverse direction — — 0,5 0,5/0,6 1,0

a
See 5.1

4.3 Load on load carriers during rail transport
The acceleration coefficients for load carriers during rail transport shall be as given in Table 3.
Table 3 — Acceleration coefficients c , c and c during rail transport
x y z
Acceleration coefficients
c , minimum vertically
z
Securing in
c , longitudinally
x
down
c , transversely
y
tilting sliding tilting sliding
longitudinal direction 0,6 1,0 — 1,0 1,0
transverse direction — — 0,5 1,0 0,7

4.4 Load on load carriers during sea transport
The acceleration coefficients for load carriers during sea transport shall be as given in Table 4.
Table 4 — Acceleration coefficients c , c and c during sea transport
x y z
Acceleration coefficients
Sea area Securing in
c , minimum ver-
z
c , longitudinally c , transversely
x y
tically down
longitudinal direction 0,3 — 0,5
A
transverse direction — 0,5 1,0
longitudinal direction 0,3 — 0,3
B
transverse direction — 0,7 1,0
longitudinal direction 0,4 — 0,2
C
transverse direction — 0,8 1,0
NOTE See IMO regulations.
A Baltic Sea bordered in west by Jylland and in north by a line between Lysekil and Skagen
B West of Sea area A bordered in north by a line between Kristians and and Montrose, in west by UK and in south
by a line between Brest and Land's End as well as the Mediterranean Sea
C Unrestricted

10

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prEN 12195-1:2008 (E)
5 Methods of calculation
5.1 General
The general requirements for a safe transport are:
 the sum of forces in any direction equals zero;
 the sum of moments in any plane equals zero.
Web lashings according to EN 12195-2, lashing chains according to EN 12195-3 and lashing steel wire ropes ac-
cording to EN 12195-4 have to sustain the forces and moments, longitudinally, transversely and vertically, the lash-
ing and the cargo unit are supposed to sustain.
Generally, load securing consists of balancing the forces of a load by locking, blocking and/or lashing. Locking, a
completely positive connection, is mainly used in the transport of containers and is not usually combined with lash-
ings. Blocking results in a positive connection in the blocked direction only and therefore is often combined with
lashings. This is taken into consideration in 5.3, 5.4 and 5.5.
The two basic lashing methods are:
 frictional lashing (see 3.1.8) which is characterized by a restraint that is produced by force on the loading
area and a positive connection in the direction vertically down;
 direct lashing (see 3.1.9) which is a completely positive connection which permits the load to make small
movements, the magnitudes of which depend on the elongation of the lashing and forces acting on the
load.
For the design of direct lashing systems a conversion factor 0,85 of the estimated friction factor will be used in com-
bination with µ without indices and is included in all appropriate equations.
The frictional lashing method is described in 5.4, the direct lashing method in 5.5.
For load of which the effectiveness of the load securing arrangements cannot be determined by means of calcula-
tions in this standard (e. g. for some non rigid goods), the calculations can be replaced by suitable tests reflecting
basic design parameters (see Clause 7).
For unstable goods in combination with frictional lashing, the increased force in the lashing due to tilting of the
goods should not exceed half of the LC. The number of lashings to be used should be the largest of the following
two calculations:

 c = 0,5 calculated with F = S
y T TF
 c = 0,6 calculated with F = 0,5 LC
y T
alternatively direct lashing should be used based on
 c = 0,6 calculated with F = LC
y R
5.2 Stability of unsecured load
The stability of a load should be determined both in longitudinal direction (x-axis) and in transverse direction (y-
axis).
Using the designations of Figure 1, the stability condition for a load is specified as follows:
F ⋅ b > F ⋅ d
z x,y x,y
11

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prEN 12195-1:2008 (E)
F
x,y
b > d
x,y
F
z
c
x,y
b > d (1)
x,y
c
z
The quantities c , c and c are the acceleration coefficients in accordance with Clause 4 (For road transport c to be
x y z y
taken as 0,5).
If the condition of equation (1) is met, a load is stable. An unstable load will have a high centre of gravity in relation
to the dimensions of the bottom surface. In the case of an unstable load the risk of tilting over has to be taken into
account.

Key
1 Center of gravity
2 Load
3 Tilting edge
Figure 1 — Stability of an unlashed load
5.3 Blocking
Blocking is the number one method for cargo securing, which always should be used if possible. Blocking is thus
used to a very large extent in reality. If the blocking of a device is strong and height enough, it prevents sliding as
well as tipping and no additional securing is required. Blocking should thus also be included under description of
the used load securing arrangement.
For the design of blocking the estimated friction factor µ is to be used.

12

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prEN 12195-1:2008 (E)


Key
1 Center of gravity
2 Load
3 Blocking device
Figure 2 — Load securing by blocking
The balance of forces in longitudinal or transverse direction are as follows:
F + F = F
B F x,y
F + µ ⋅ m ⋅ c ⋅ g = m ⋅ c ⋅ g
B z x,y
F = (c − µ ⋅ c ) m ⋅ g (2)
B x,y z
The equation for calculating the blocking capacity BC is as follows (see also Figure 2):
BC > (c − µ ⋅ c ) m ⋅ g (3)
x,y z
where
BC is the blocking capacity;
c , c and c are the acceleration coefficients according to Clause 4;
x y z
g is the gravitational acceleration;
m is the mass of the load;
µ is the estimated friction factor according to Annex B.

Blocking is the number one method for cargo securing, which always should be used if possible. Blocking of unsta-
ble load without lashing is only possible, if the blocking device is also designed to avoid tilting of the load, e.g. by
bracing (see 5.2).
5.4 Frictional lashing
5.4.1 General
Frictional lashing, as shown in Figure 3, consists of tensioning the lashings to the tension force F so as to increase
T
the friction force at the contact surface of the load to avoid any sliding of the load.
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prEN 12195-1:2008 (E)
The tensioning device of the lashings, if more than one, should if practically possible be arranged on the opposing
sides of the load.
Because of practical reasons, e. g. setting behaviour of the load, retightening after short travelling is recommended.
Indicated by the surface of the load, corner protectors should be used.
The calculations in the standard are based on theoretical principles. Operational factors can positively or negatively
impact the required number of lashings, e. g.
 retensioning not feasible,
 self-tensioning effect,
 influence of the corner frictions.
To compensate for calculation uncertainties a
...

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