Railway applications -- Polymeric composite sleepers, bearers and transoms

This document specifies various test methods to ensure the performance of polymeric composite and reinforced polymeric composite sleepers, bearers and transoms for use in tracks. It is applicable to the sleepers, bearers and transoms to be installed in tracks with or without a ballast.

Applications ferroviaires -- Traverses et supports en matériaux composites à matrice polymère

General Information

Status
Published
Publication Date
22-Nov-2020
Current Stage
5060 - Close of voting Proof returned by Secretariat
Start Date
04-Aug-2020
Completion Date
03-Aug-2020
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INTERNATIONAL ISO
STANDARD 12856-2
First edition
2020-11
Railway applications — Polymeric
composite sleepers, bearers and
transoms —
Part 2:
Product testing
Applications ferroviaires — Traverses et supports en matériaux
composites à matrice polymère —
Partie 2: Essais de produit
Reference number
ISO 12856-2:2020(E)
ISO 2020
---------------------- Page: 1 ----------------------
ISO 12856-2:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2020

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 12856-2:2020(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Symbols and abbreviated terms ........................................................................................................................................................... 1

5 Product characteristics .................................................................................................................................................................................. 3

5.1 General ........................................................................................................................................................................................................... 3

5.2 Bending resistance .............................................................................................................................................................................. 3

5.2.1 Test arrangements .......................................................................................................................................................... 3

5.2.2 Initial reference test loads ....................................................................................................................................10

5.2.3 Test procedures at the centre section for the negative bending moments .................10

5.2.4 Test procedures at the centre section for the positive bending moments ..................14

5.2.5 Test procedures at the rail seat ........................................................................................................................18

5.3 Tests with geometric ballast plate (GBP) or with flat plate (FP) at rail seat ..................................21

5.3.1 Stiffness with GBP or with FP at rail seat ................................................................................................21

5.3.2 Compression test with GBP or with FP at rail seat ..........................................................................21

5.4 Thermal expansion ...........................................................................................................................................................................22

5.4.1 Principle ...............................................................................................................................................................................22

5.4.2 Apparatus ............................................................................................................................................................................22

5.4.3 Procedure ............................................................................................................................................................................23

5.5 Interface between the rail and the sleeper ..................................................................................................................24

5.5.1 Permanent deformation of screw/insert as a function of temperature ........................24

5.5.2 Fastening system ..........................................................................................................................................................26

5.5.3 Electrical resistance ...................................................................................................................................................27

5.5.4 Screw, spike, cast-in and glued-in fastening components .........................................................27

5.6 Fire ......... .........................................................................................................................................................................................................27

5.7 System Test ..............................................................................................................................................................................................27

Annex A (informative) Geometric ballast plate (GBP) ....................................................................................................................28

Annex B (informative) Test procedures for stiffness measurement of polymeric composite

sleeper or bearer with GBP ....................................................................................................................................................................31

Annex C (informative) Test procedures for stiffness measurement of polymeric composite

sleeper with flat plate (FP) .....................................................................................................................................................................38

Annex D (informative) System test ......................................................................................................................................................................39

Bibliography .............................................................................................................................................................................................................................42

© ISO 2020 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO 12856-2:2020(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.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).

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. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/ patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the

World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/

iso/ foreword .html.

This document was prepared by Technical Committee ISO/TC 269, Railway applications, Subcommittee

SC 1, Infrastructure.
A list of all parts in the ISO 12856 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2020 – All rights reserved
---------------------- Page: 4 ----------------------
ISO 12856-2:2020(E)
Introduction

This document is used as the technical basis for transactions between corresponding parties (purchaser

– supplier).
© ISO 2020 – All rights reserved v
---------------------- Page: 5 ----------------------
INTERNATIONAL STANDARD ISO 12856-2:2020(E)
Railway applications — Polymeric composite sleepers,
bearers and transoms —
Part 2:
Product testing
1 Scope

This document specifies various test methods to ensure the performance of polymeric composite and

reinforced polymeric composite sleepers, bearers and transoms for use in tracks. It is applicable to the

sleepers, bearers and transoms to be installed in tracks with or without a ballast.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements 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 7500-1, Metallic materials — Calibration and verification of static uniaxial testing machines — Part 1:

Tension/compression testing machines — Calibration and verification of the force-measuring system

ISO 12856-3:— , Railway applications — Polymeric composite sleepers, bearers and transoms — Part 3:

General requirements
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 12856-3 apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
4 Symbols and abbreviated terms

For the purposes of this document, the symbols and abbreviated terms listed in Table 1 apply.

Table 1 — Symbols
Symbol/
Abbrevi- Description Unit
ated term
low frequency dynamic bedding modulus of polymeric composite sleeper or bearer
C N/mm
dyn
measured with GBP

static bedding modulus of polymeric composite sleeper or bearer measured with ge-

C N/mm
max
ometric ballast plate (GBP)
d acceptable displacement of fatigue test as a maintenance policy mm
fat,lim
d deformation of the sleeper in the compression test under F mm
0c r0
1) Under preparation. Stage at the time of publication: ISO/DIS 12856-3:2020.
© ISO 2020 – All rights reserved 1
---------------------- Page: 6 ----------------------
ISO 12856-2:2020(E)
Table 1 (continued)
Symbol/
Abbrevi- Description Unit
ated term
d deformation of the sleeper in the compression test under k × F mm
1c 1s r0
d upper limit deformation related to the exceptional test load mm
1s,lim
d deformation of the sleeper in the compression test under k × F mm
2c 2s r0
d upper limit deformation related to the accidental test load mm
2s,lim

variation of static and dynamic stiffness before and after the fatigue test at the centre

Δk MN/m
section for positive bending moments

variation of static and dynamic stiffness before and after the fatigue test at the centre

Δk MN/m
c,n
section for negative bending moments

the variation of static and dynamic stiffness before and after the fatigue test at the

Δk MN/m
rail seat

design distance between the centre line of the rail seat to the longitudinal girders of

e m
bridge
E thickness of ballast bed in a ballast box mm
F positive test load at the centre section of the sleeper kN
F positive initial test load at the centre section of the sleeper kN
F negative test load at the centre section of the sleeper kN
c,n
F positive fatigue test load at the centre section of the sleeper kN
c,fat
F negative fatigue test load at the centre section of the sleeper kN
c,fat,n

constant load applied for permanent deformation test at the centre section for negative

F kN
c,perm,n
bending moments
FP flat plate n/a
F positive test load for the rail seat section kN

F maximum positive test load at the rail seat section which cannot be increased kN

F positive fatigue test load for the rail seat section kN
r,fat
F positive initial reference test load for the rail seat section kN
GBP geometric ballast plate n/a

k low frequency dynamic stiffness on 10 cycles under applying a cyclic force of F (= MN/m

c,dyn1 c,min
0,1 · F ) to F (= 0,5 · F ) at (5 ±1) Hz for 1 000 cycles
c0 c,test1 c0

k Low frequency dynamic stiffness on 10 cycles under applying a cyclic force of F (= MN/m

c,dyn2 c,min
0,1 · F ) to F (= F ) at (5 ±1) Hz for 1 000 cycles
c0 c,test2 c0

static stiffness of the fifth loading at the centre section for negative bending loads be-

k MN/m
c,n,stat1
tween (0.1· F ) and (0.5 · F )
c0,n c0,n

static stiffness of the fifth loading at the centre section for negative bending loads be-

k MN/m
c,n,stat2
tween (0.1 · F ) and F
c0,n c0,n

low frequency dynamic stiffness of polymeric composite sleeper or bearer measured

k MN/m
dyn
with GBP

k static stiffness of polymeric composite sleeper or bearer measured with GBP MN/m

max

low frequency dynamic stiffness on 10 cycles under applying a cyclic force of F (=

r,min
k MN/m
r,dyn1
0,1 · F ) to F (= 0,5 · F ) at (5 ±1) Hz for 1 000 cycles
r0 r,test1 r0

low frequency dynamic stiffness on 10 cycles under applying a cyclic force of F (=

r,min
k MN/m
r,dyn2
0,1 · F ) to F (= F ) at (5 ±1) Hz for 1 000 cycles
r0 r,test2 r0
k load factor of exceptional test load level n/a
k load factor of accidental test load level n/a

static coefficient to be used for calculation of F at the end of fatigue test and provided

k n/a
by the purchaser
L shoulder length of ballast bed in a ballast box mm
2 © ISO 2020 – All rights reserved
---------------------- Page: 7 ----------------------
ISO 12856-2:2020(E)
Table 1 (continued)
Symbol/
Abbrevi- Description Unit
ated term
L design distance between centre lines of the rail seat m

L length measured on the opposite side of top of sleeper, bearer or transom for Thermal m

expansion test

L design distance between the centre line of the rail seat to the edge of the sleeper at

the bottom

design distance between the articulated supports centre lines for the test arrangement

L m
at the rail seat section
L length between the supports on the longitudinal girders of the bridge m

L length measured on the top of the sleeper, bearer or transom for Thermal expansion test m

M characteristic bending moment for transom kN.m
k,b
M negative characteristic bending moment at centre station kN.m
k,c,neg
M positive characteristic bending moment at centre station kN.m
k,c,pos
M positive characteristic bending moment at rail seat kN.m
k,r,pos
Q nominal wheel load (static wheel load) kN
nom
5 Product characteristics
5.1 General

This clause defines the testing regime and rules for the acceptance of polymeric composite sleepers,

bearers and transoms.

The bending tests are defined for ballasted track. For ballastless track, the test arrangement shall be

reviewed in order to adapt to the real configuration of the track.
5.2 Bending resistance
5.2.1 Test arrangements
5.2.1.1 Rail seat section for the positive load test for sleepers

The arrangement for the rail seat positive load test is shown in Figure 1; the value of L in relation to L

r p
is detailed in Table 2.
The load, F , is applied perpendicularly to the base of the sleeper.
The end of the sleeper opposite to the end being tested shall not be fixed.
© ISO 2020 – All rights reserved 3
---------------------- Page: 8 ----------------------
ISO 12856-2:2020(E)
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat

+20 mm, width: 140 ± 1 mm, thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 + mm,

thickness: 15 mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C ≤ 4 N/mm )

4 polymeric composite sleeper without the fastening system and with baseplate (if used)

5 standard rail pad as defined by the purchaser

6 steel tapered packing compensating the inclination of the rail seat (minimum length: length of the

standard rail pad +20 mm, width: 140 ± 1 mm (this width can be reduced in line with the real

width of the rail foot used in track), thickness: minimum 12 mm and minimum hardness Brinell:

HBW > 240)

C , C locations of the vertical displacement measurement on the axis of the articulated support

1 2
and C
F positive test load for the rail seat section

L design distance between the articulated supports centre lines for the test arrangement at the rail seat

section

L design distance between the centre line of the rail seat to the edge of the sleeper at the bottom

Figure 1 — Test arrangement at the rail seat section for the positive load test

The deformation, d, measured during the tests on the rail seat is calculated with Formula (1):

CC+
d=−C (1)
4 © ISO 2020 – All rights reserved
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ISO 12856-2:2020(E)
Table 2 — Value of L in relation to L
r p
L L
p r
m m
L < 0,349 0,3
0,350 ≤ L < 0,399 0,4
0,400 ≤ L < 0,449 0,5
L ≥ 0,450 0,6

The displacement measuring instruments shall be capable of measuring the displacement within

±0,02 mm.

The force measuring instruments shall conform to ISO 7500-1, class 2, over the required range of force.

5.2.1.2 Centre section for the negative load test for sleepers
The arrangement for the negative centre load test is shown in Figure 2.
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat +20 mm,

width: 140 ± 1 mm, thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 mm,

thickness: 15 mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C ≤ 4 N/mm )

4 polymeric composite sleeper with or without the fastening system and the baseplate (if used);

5 standard rail pad as defined by the purchaser

6 steel tapered packing compensated the inclination of the rail seat (minimum length: length of the

standard

rail pad +20 mm, width: 140 ± 1 mm [this width can be reduced in line with the real width of the rail foot

used in track], thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

C , C locations of the vertical displacement measurement on the axis of the articulated support of the rail

1 2
and C seats and the centre of the sleeper
F negative reference test load at the centre section of the sleeper
c,n
L design distance between centre lines of the rail seat
Figure 2 — Test arrangement at the centre section for the negative load test

The deformation, d, measured during the tests on the centre section for the negative load is calculated

using Formula (1).
© ISO 2020 – All rights reserved 5
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ISO 12856-2:2020(E)

The displacement measuring instruments shall be capable of measuring the displacement within

±0,02 mm.

The force measuring instruments shall conform to ISO 7500-1, class 2, over the required range of force.

5.2.1.3 Centre section for the positive load test for sleepers
The test arrangement for the positive centre load test is shown in Figure 3.
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat +20 mm,

width: 140 ± 1 mm, thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 mm,

thickness: 15 + mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C 4 N/mm )

4 polymeric composite sleeper with or without the fastening system and without the baseplate

C , C locations of the vertical displacement measurement on the axis of the articulated support

1 2
and C
F positive test load at the centre section of the sleeper
L design distance between centre lines of the rail seat
Figure 3 — Test arrangement at the centre section for the positive load test

The deformation, d, measured during the tests on the centre section for the negative load is calculated

using Formula (1).

The displacement measuring instruments shall be capable of measuring the displacement within

±0,02 mm.

The force measuring instruments shall conform to ISO 7500-1, class 2, over the required range of force.

5.2.1.4 Rail seat section for the positive load test for bearers
The arrangement for the rail seat positive load at a rail seat:
— next to the end of the bearer, and
— with direct support of the rail (i.e. fastening system without a baseplate),
is shown in Figure 1. The value of L in relation to L is detailed in Table 2.
r p
6 © ISO 2020 – All rights reserved
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ISO 12856-2:2020(E)
The load, F , is applied perpendicularly to the base of the bearer.

The end of the bearer opposite to the end being tested shall be supported during the test in order to

compensate the influence of the weight of the bearers on the test bending moment. Alternatively, the

bearer may be cut off at the distance, L , from the centre line of the rail.
5.2.1.5 Centre section for the negative load test for bearers
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat +20 mm,

width: 140 ± 01 mm, thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 mm,

thickness: 15 mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C ≤ 4 N/mm )

4 polymeric composite bearer without the fastening system and with the baseplate (if used)

L for gauges of 1 435 mm, L = 1,5 m. For other gauges, the length shall be adapted

C , C locations of the vertical displacement measurement on the axis of the articulated support

1 2
and C
F negative test load at the centre section of the sleeper
c,n
Figure 4 — Test arrangement at the centre section for the negative load test
© ISO 2020 – All rights reserved 7
---------------------- Page: 12 ----------------------
ISO 12856-2:2020(E)
5.2.1.6 Centre section for the positive load test for bearers
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat +20 mm,

width: 140 ± 1 mm, thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 mm,

thickness: 15 mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C ≤ 4 N/mm )

4 polymeric composite bearer without the fastening system and with the baseplate (if used)

L for gauges of 1 435 mm, L = 1,5 m. For other gauges, the length shall be adapted

C , C locations of the vertical displacement measurement on the axis of the articulated support

1 2
and C
F positive test load at the centre section of the sleeper
Figure 5 — Test arrangement at the centre section for the positive load test
5.2.1.7 Centre section for the load test for transom

The test arrangement shall be approved by the purchaser, depending on the bridge.

NOTE This test arrangement generates positive or negative bending moments depending on the eccentricity,

e, of the supports on the longitudinal girders of the bridge. However, this test arrangement is only used for the

tests in 5.2.3, "Test procedures at the centre section for the negative bending moments".

If support conditions for the transoms on the bridge are different to the test arrangement in Figure 6,

this should be taken into account in the calculation of M .
k,b

Any modification (for example cut-outs to fasten the transom) should be carried out on the transom

before testing.
8 © ISO 2020 – All rights reserved
---------------------- Page: 13 ----------------------
ISO 12856-2:2020(E)
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat +20 mm,

width: 140 ± 1 mm [this width can be reduced in line with the real width of the rail foot used in track],

thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)
+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 mm,

thickness: 15 mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C ≤ 4 N/mm )
4 transom
5 rib plate as defined by the purchaser
6 standard rail pad as defined by the purchaser
7 rail as defined by the purchaser

e design distance between the centre line of the rail seat to the longitudinal girders of bridge

L length between the supports on the longitudinal girders of the bridge

C , C , locations of the vertical displacement measurement on the axis of the articulated support

1 2
C , C
3 4
and C
F negative test load at the centre section of the sleeper
c,n
L design distance between centre lines of the rail seat
Figure 6 — Test arrangement at the centre section for the load test

The deformation, d, measured during the tests on the rail seat is calculated with the

Formulae (2), (3) and (4):
Le−
 
d=−CC + CC− ⋅ (at left rail seat) (2)
 
25 15
 
 
d=−CC + CC− ⋅ (at right rail seat) (3)
 
45 15
 
CC+
d=−C (at sleeper centre) (4)
© ISO 2020 – All rights reserved 9
---------------------- Page: 14 ----------------------
ISO 12856-2:2020(E)
5.2.2 Initial reference test loads
5.2.2.1 Initial reference test loads for sleepers

F is calculated from the geometry given in Figure 1 and values from Table 3 using Formula (5):

k,r,pos
F = (in kN) (5)
L −01,
Table 3 — Value of F in relation to L
r0 r
L 0,3 0,4 0,5 0,6
F 20 M 13 M 10 M 8 M
r0 k,r,pos k,r,pos k,r,pos k,r,pos

F and F are calculated from the geometry given respectively in Figures 2 and 3 using

c0 c0,n
Formulae (6) and (7):
k,c,pos
F = (in kN) (6)
L −01,
k,c,neg
F = (in kN) (7)
c0,n
5.2.2.2 Initial reference test loads for bearers

F is calculated from the geometry given in Figure 1 and values from Table 3 using Formula (5) with

L = 0,6 m.

F and F are calculated from the geometry given respectively in Figures 4 and 5 using

c0 c0,n

Formulae (6) and (7) with L = 1,5 m for a gauge of 1 435 mm. For other gauges, the length shall be

adapted.
5.2.2.3 Initial reference test load for transoms

F are calculated from the geometry given respectively in Figure 6 using Formula (8).

c0,n
2⋅M
k,b
F = (8)
c0,n
5.2.3 Test procedures at the centre section for the negative bending moments
5.2.3.1 Stiffness at the centre section

The stiffness test at the centre section for the design approval test is performed by applying a load with

measurement of the deformation of the sleeper, bearer or transom.

The test arrangement shall be in accordance with 5.2.1.2 for sleepers, with 5.2.1.5 for bearers and with

5.2.1.7 for transoms.

The static and dynamic stiffness tests shall be carried out at a room temperature of (23 ± 5) °C if no

specific temperature has been fixed by the purchaser.

NOTE Control of room temperature is important for establishing an accurate result. Any variation beyond

set tolerances affects the result.
10 © ISO 2020 – All rights reserved
---------------------- Page: 15 ----------------------
ISO 12856-2:2020(E)
Static stiffness:

Apply a vertical force F to the actuator. Then reduce the force to (0,07 · F ) and repeat this cycle

c0,n c0,n

of loading and unloading three more times with a speed of between 60 and 120 kN/min. Maintain the

applied force (0,07 · F ), then record the displacement as a function of the load whilst increasing the

c0,n
applied force to F (this loading
...

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 12856-2
ISO/TC 269/SC 1
Railway applications — Polymeric
Secretariat: AFNOR
composite sleepers, bearers and
Voting begins on:
2020-06-08 transoms —
Voting terminates on:
Part 2:
2020-08-03
Product testing
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 SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 12856-2:2020(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. ISO 2020
---------------------- Page: 1 ----------------------
ISO/FDIS 12856-2:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2020

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/FDIS 12856-2:2020(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Symbols and abbreviated terms ........................................................................................................................................................... 1

5 Product characteristics .................................................................................................................................................................................. 3

5.1 General ........................................................................................................................................................................................................... 3

5.2 Bending resistance .............................................................................................................................................................................. 3

5.2.1 Test arrangements .......................................................................................................................................................... 3

5.2.2 Initial reference test loads ....................................................................................................................................10

5.2.3 Test procedures at the centre section for the negative bending moments .................10

5.2.4 Test procedures at the centre section for the positive bending moments ..................14

5.2.5 Test procedures at the rail seat ........................................................................................................................18

5.3 Tests with geometric ballast plate (GBP) or with flat plate (FP) at rail seat ..................................21

5.3.1 Stiffness with GBP or with FP at rail seat ................................................................................................21

5.3.2 Compression test with GBP or with FP at rail seat ..........................................................................21

5.4 Thermal expansion ...........................................................................................................................................................................22

5.4.1 Principle ...............................................................................................................................................................................22

5.4.2 Apparatus ............................................................................................................................................................................22

5.4.3 Procedure ............................................................................................................................................................................23

5.5 Interface between the rail and the sleeper ..................................................................................................................24

5.5.1 Permanent deformation of screw/insert in function of temperature ............................24

5.5.2 Fastening system ..........................................................................................................................................................26

5.5.3 Electrical resistance ...................................................................................................................................................27

5.5.4 Screw, spike, cast-in and glued-in fastening components .........................................................27

5.6 Fire ......... .........................................................................................................................................................................................................27

5.7 System Test ..............................................................................................................................................................................................27

Annex A (informative) Geometric ballast plate (GBP) ....................................................................................................................28

Annex B (informative) Test procedures for stiffness measurement of polymeric composite

sleeper with GBP ...............................................................................................................................................................................................31

Annex C (informative) Test procedures for stiffness measurement of polymeric composite

sleeper with flat plate (FP) .....................................................................................................................................................................38

Annex D (informative) System test ......................................................................................................................................................................39

Bibliography .............................................................................................................................................................................................................................42

© ISO 2020 – All rights reserved iii
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ISO/FDIS 12856-2:2020(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.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).

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. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/ patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the

World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/

iso/ foreword .html.

This document was prepared by Technical Committee ISO/TC 269, Railway applications, Subcommittee

SC 1, Infrastructure.
A list of all parts in the ISO 12856 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2020 – All rights reserved
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ISO/FDIS 12856-2:2020(E)
Introduction

This document is used as the technical basis for transactions between corresponding parties (purchaser

– supplier).
© ISO 2020 – All rights reserved v
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 12856-2:2020(E)
Railway applications — Polymeric composite sleepers,
bearers and transoms —
Part 2:
Product testing
1 Scope

This document specifies various test methods to ensure the performance of polymeric composite and

reinforced polymeric composite sleepers, blocks or bearers for use in tracks. It is applicable to the

sleepers, blocks or bearers to be installed in tracks with or without a ballast.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements 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 7500-1, Metallic materials — Calibration and verification of static uniaxial testing machines — Part 1:

Tension/compression testing machines — Calibration and verification of the force-measuring system

ISO 12856-1, Plastics — Plastic railway sleepers for railway applications (railroad ties) — Part 1: Material

characteristics
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 12856-1 apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
4 Symbols and abbreviated terms

For the purposes of this document, the symbols and abbreviated terms listed in Table 1 apply.

Table 1 — Symbols
Symbol/
Abbrevi- Description Unit
ated term
low frequency dynamic bedding modulus of polymeric composite sleeper or bearer
C N/mm
dyn
measured with GBP

static bedding modulus of polymeric composite sleeper or bearer measured with ge-

C N/mm
max
ometric ballast plate (GBP)

acceptable displacement of fatigue test at the centre section for negative bending as a

d mm
fat,lim
maintenance policy
d deformation of the sleeper in the compression test under F mm
0c r0
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ISO/FDIS 12856-2:2020(E)
Table 1 (continued)
Symbol/
Abbrevi- Description Unit
ated term
d deformation of the sleeper in the compression test under k × F mm
1c 1s r0
d upper limit deformation related to the exceptional test load mm
1s,lim
d deformation of the sleeper in the compression test under k × F mm
2c 2s r0
d upper limit deformation related to the accidental test load mm
2s,lim

variation of static and dynamic stiffness before and after the fatigue test at the centre

Δk MN/m
section for positive bending moments

variation of static and dynamic stiffness before and after the fatigue test at the centre

Δk MN/m
c,n
section for negative bending moments

the variation of static and dynamic stiffness before and after the fatigue test at the

Δk MN/m
rail seat

design distance between the centre line of the rail seat to the longitudinal girders of

E m
bridge
E thickness of ballast bed in a ballast box mm
F positive test load at the centre section of the sleeper kN
F negative test load at the centre section of the sleeper kN
c,n
F positive fatigue test load at the centre section of the sleeper kN
c,fat
F negative fatigue test load at the centre section of the sleeper kN
c,fat,n

constant load applied for permanent deformation test at the centre section for negative

F kN
c,perm,n
bending moments
FP flat plate n/a
F positive test load for the rail seat section kN

F maximum positive test load at the rail seat section which cannot be increased kN

F positive fatigue test load for the rail seat section kN
r,fat
F positive initial reference test load for the rail seat section kN
GBP geometric ballast plate n/a

k low frequency dynamic stiffness on 10 cycles under applying a cyclic force of F (= MN/m

c,dyn1 c,min
0,1 · F ) to F (= 0,5 · F ) at (5 ±1) Hz for 1 000 cycles
c0 c,test1 c0

static stiffness of the fifth loading at the centre section for negative bending loads be-

k MN/m
c,n,stat1
tween (0.1・F ) and (0.5・F )
c0,n c0,n

static stiffness of the fifth loading at the centre section for negative bending loads be-

k MN/m
c,n,stat2
tween (0.1・F ) and F
c0,n c0,n

low frequency dynamic stiffness of polymeric composite sleeper or bearer measured

k MN/m
dyn
with GBP

k static stiffness of polymeric composite sleeper or bearer measured with GBP MN/m

max

low frequency dynamic stiffness on 10 cycles under applying a cyclic force of F (=

c,min
k MN/m
r,dyn2
0,1 · F ) to F (= 0,5 · F ) at (5 ±1) Hz for 1 000 cycles
c0 c,test2 c0
k load factor of exceptional test load level n/a
1s
k load factor of accidental test load level n/a
2s

static coefficient to be used for calculation of F at the end of fatigue test and provided

k n/a
by the purchaser
L shoulder length of ballast bed in a ballast box mm
L design distance between centre lines of the rail seat m

L design distance between the centre line of the rail seat to the edge of the sleeper at

the bottom

design distance between the articulated supports centre lines for the test arrangement

L m
at the rail seat section
2 © ISO 2020 – All rights reserved
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ISO/FDIS 12856-2:2020(E)
Table 1 (continued)
Symbol/
Abbrevi- Description Unit
ated term
L length between the supports on the longitudinal girders of the bridge m
M characteristic bending moment for transom kN.m
k,b
M negative characteristic bending moment at centre station kN.m
k,c,neg
M positive characteristic bending moment at centre station kN.m
k,c,pos
M positive characteristic bending moment at rail seat kN.m
k,r,pos
Q nominal wheel load (static wheel load) kN
nom
5 Product characteristics
5.1 General

This clause defines the testing regime and rules for the acceptance of polymeric composite sleepers and

bearers.

The bending tests are defined for ballasted track. For ballastless track, the test arrangement shall be

reviewed in order to adapt to the real configuration of the track.
5.2 Bending resistance
5.2.1 Test arrangements
5.2.1.1 Rail seat section for the positive load test for sleepers

The arrangement for the rail seat positive load test is shown in Figure 1; the value of L in relation to L

r p
is detailed in Table 2.
The load, F , is applied perpendicularly to the base of the sleeper.
The end of the sleeper opposite to the end being tested shall not be fixed.
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ISO/FDIS 12856-2:2020(E)
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat

+20 mm, width: 140 ± 1 mm, thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 + mm,

thickness: 15 mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C ≤ 4 N/mm )

4 polymeric composite sleeper without the fastening system and with baseplate (if used)

5 standard rail pad as defined by the purchaser

6 steel tapered packing compensating the inclination of the rail seat (minimum length: length of the

standard rail pad +20 mm, width: 140 ± 1 mm (this width can be reduced in line with the real

width of the rail foot used in track), thickness: minimum 12 mm and minimum hardness Brinell:

HBW > 240)

C , C locations of the vertical displacement measurement on the axis of the articulated support

1 2
and C
F positive test load for the rail seat section

L design distance between the articulated supports centre lines for the test arrangement at the rail seat

section

L design distance between the centre line of the rail seat to the edge of the sleeper at the bottom

Figure 1 — Test arrangement at the rail seat section for the positive load test

The deformation, d, measured during the tests on the rail seat is calculated with Formula (1):

CC+
d=−C (1)
4 © ISO 2020 – All rights reserved
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ISO/FDIS 12856-2:2020(E)
Table 2 — Value of L in relation to L
r p
L L
p r
m m
L < 0,349 0,3
0,350 ≤ L < 0,399 0,4
0,400 ≤ L < 0,449 0,5
L ≥ 0,450 0,6

The displacement measuring instruments shall be capable of measuring the displacement within

±0,02 mm.

The force measuring instruments shall conform to ISO 7500-1, class 2, over the required range of force.

5.2.1.2 Centre section for the negative load test for sleepers
The arrangement for the negative centre load test is shown in Figure 2.
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat +20 mm,

width: 140 ± 1 mm, thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 mm,

thickness: 15 mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C ≤ 4 N/mm )

polymeric composite sleeper with or without the fastening system and the baseplate (if used); standard

rail pad as defined by the purchaser

steel tapered packing compensated the inclination of the rail seat (minimum length: length of the

standard rail pad +20 mm, width: 140 ± 1 mm [this width can be reduced in line with the real width of

the rail foot used in track], thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

C , C

locations of the vertical displacement measurement on the axis of the articulated support of the rail seats

1 2
and C
3 and the centre of the sleeper
c,n negative reference test load at the centre section of the sleeper
L design distance between centre lines of the rail seat
Figure 2 — Test arrangement at the centre section for the negative load test

The deformation, d, measured during the tests on the centre section for the negative load is calculated

using Formula (1).
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ISO/FDIS 12856-2:2020(E)

The displacement measuring instruments shall be capable of measuring the displacement within

±0,02 mm.

The force measuring instruments shall conform to ISO 7500-1, class 2, over the required range of force.

5.2.1.3 Centre section for the positive load test for sleepers
The test arrangement for the positive centre load test is shown in Figure 3.
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat +20 mm,

width: 140 ± 1 mm, thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 mm,

thickness: 15 + mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C 4 N/mm )

4 polymeric composite sleeper with or without the fastening system and without the baseplate

C , C locations of the vertical displacement measurement on the axis of the articulated support

1 2
and C
F positive test load at the centre section of the sleeper
L design distance between centre lines of the rail seat
Figure 3 — Test arrangement at the centre section for the positive load test

The deformation, d, measured during the tests on the centre section for the negative load is calculated

using Formula (1).

The displacement measuring instruments shall be capable of measuring the displacement within

±0,02 mm.

The force measuring instruments shall conform to ISO 7500-1, class 2, over the required range of force.

5.2.1.4 Rail seat section for the positive load test for bearers
The arrangement for the rail seat positive load at a rail seat:
— next to the end of the bearer, and
— with direct support of the rail (i.e. fastening system without a baseplate),
is shown in Figure 1. The value of L in relation to L is detailed in Table 2.
r p
6 © ISO 2020 – All rights reserved
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ISO/FDIS 12856-2:2020(E)
The load, F , is applied perpendicularly to the base of the bearer.

The end of the bearer opposite to the end being tested shall be supported during the test in order to

compensate the influence of the weight of the bearers on the test bending moment. Alternatively, the

bearer may be cut off at the distance, L , from the centre line of the rail.
5.2.1.5 Centre section for the negative load test for bearers
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat +20 mm,

width: 140 ± 01 mm, thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 mm,

thickness: 15 mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C ≤ 4 N/mm )

4 polymeric composite bearer without the fastening system and with the baseplate (if used)

L for gauges of 1 435 mm, L = 1,5 m. For other gauges, the length shall be adapted

C , C locations of the vertical displacement measurement on the axis of the articulated support

1 2
and C
F negative test load at the centre section of the sleeper
c,n
Figure 4 — Test arrangement at the centre section for the negative load test
© ISO 2020 – All rights reserved 7
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ISO/FDIS 12856-2:2020(E)
5.2.1.6 Centre section for the positive load test for bearers
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat +20 mm,

width: 140 ± 1 mm, thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)

+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 mm,

thickness: 15 mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C ≤ 4 N/mm )

4 polymeric composite bearer without the fastening system and with the baseplate (if used)

L for gauges of 1 435 mm, L = 1,5 m. For other gauges, the length shall be adapted

C , C locations of the vertical displacement measurement on the axis of the articulated support

1 2
and C
F positive test load at the centre section of the sleeper
Figure 5 — Test arrangement at the centre section for the positive load test
5.2.1.7 Centre section for the load test for transom

The test arrangement shall be approved by the purchaser, depending on the bridge.

NOTE 1 This test arrangement generates positive or negative bending moments depending on the eccentricity,

e, of the supports on the longitudinal girders of the bridge. However, this test arrangement is only used for the

tests in 5.2.3, "Test procedures at the centre section for the negative bending moments".

If support conditions for the transoms on the bridge are different to the test arrangement in Figure 6,

this should be taken into account in the calculation of M .
k,b

Any modification (for example cut-outs to fasten the transom) should be carried out on the transom

before testing.
8 © ISO 2020 – All rights reserved
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ISO/FDIS 12856-2:2020(E)
Key
1 rigid support

2 articulated support and steel plate (minimum length: bottom width of the sleeper at the rail seat +20 mm,

width: 140 ± 1 mm [this width can be reduced in line with the real width of the rail foot used in track],

thickness: minimum 12 mm and minimum hardness Brinell: HBW > 240)
+10

resilient pad (minimum length: bottom width of the sleeper at the rail seat + 20 mm, width: 140 mm,

thickness: 15 mm and static bedding modulus: static secant bedding modulus measured between

0,3 MPa and 2 MPa: 1 ≤ C ≤ 4 N/mm )
4 transom
5 rib plate as defined by the purchaser
6 standard rail pad as defined by the purchaser
7 rail as defined by the purchaser

e design distance between the centre line of the rail seat to the longitudinal girders of bridge

L length between the supports on the longitudinal girders of the bridge

C , C , locations of the vertical displacement measurement on the axis of the articulated support

1 2
C , C
3 4
and C
F negative test load at the centre section of the sleeper
c,n
L design distance between centre lines of the rail seat
Figure 6 — Test arrangement at the centre section for the load test

The deformation, d, measured during the tests on the rail seat is calculated with the

Formulae (2), (3) and (4):
Le−
d=−CC −C ⋅ (at left rail seat) (2)
21 5
d=−CC −C ⋅ (at right rail seat) (3)
41 5
CC−
d=−C (at sleeper centre) (4)
© ISO 2020 – All rights reserved 9
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ISO/FDIS 12856-2:2020(E)
5.2.2 Initial reference test loads
5.2.2.1 Initial reference test loads for sleepers

F is calculated from the geometry given in Figure 1 and values from Table 3 using Formula (5):

k,r,pos
F = (in kN) (5)
L −01,
Table 3 — Value of F in relation to L
r0 r
L 0,3 0,4 0,5 0,6
F 20 M 13 M 10 M 8 M
r0 k,r,pos k,r,pos k,r,pos k,r,pos

F and F are calculated from the geometry given respectively in Figures 2 and 3 using

c0 c0,n
Formulae (6) and (7):
k,c,pos
F = (in kN) (6)
L −01,
k,c,neg
F = (in kN) (7)
c0,n
5.2.2.2 Initial reference test loads for bearers

F is calculated from the geometry given in Figure 1 and values from Table 3 using Formula (5) with

L = 0,6 m.

F and F are calculated from the geometry given respectively in Figures 4 and 5 using

c0 c0,n

Formulae (6) and (7) with L = 1,5 m for a gauge of 1 435 mm. For other gauges, the length shall be

adapted.
5.2.2.3 Initial reference test load for transoms

F are calculated from the geometry given respectively in Figure 6 using Formula (8).

c0,n
2⋅M
k,b
F = (8)
c0,n
5.2.3 Test procedures at the centre section for the negative bending moments
5.2.3.1 Stiffness at the centre section

The stiffness test at the centre section for the design approval test is performed by applying a load with

measurement of the deformation of the sleeper and of the bearer.

The test arrangement shall be in accordance with 5.2.1.2 for sleepers, with 5.2.1.5 for bearers and with

5.2.1.7 for transoms.

The static and dynamic stiffness tests shall be carried out at a room temperature of (23 ± 5) °C if no

specific temperature has been fixed by the purchaser.

NOTE Control of room temperature is important for establishing an accurate result. Any variation beyond

set tolerances affects the result.
10 © ISO 2020 – All rights reserved
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ISO/FDIS 12856-2:2020(E)
Static stiffness:

Apply a vertical force F to the actuator. Then reduce the force to (0,07 · F ) and repeat this cycle

c0,n c0,n

of loading and unloading three more times with a speed of between 60 and 120 kN/min. Maintain the

applied force (0,07 · F ), then record the displacement as a function of the load whilst increasing the

c0,n
applied force to F (this loading corresponds to the fifth loading).
c0,n
Key
1 fifth loading: temporal laps to record the displacement whilst increas
...

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