FprEN ISO 12957-2

SLOVENSKI STANDARD
oSIST prEN ISO 12957-2:2023
01-december-2023
Geosintetika - Ugotavljanje tornih značilnosti - 2. del: Preskus na nagnjeni ravnini
(ISO/DIS 12957-2:2023)
Geosynthetics - Determination of friction characteristics - Part 2: Inclined plane test
(ISO/DIS 12957-2:2023)
Geokunststoffe - Bestimmung der Reibungseigenschaften - Teil 2: Schiefe-Ebene-
Versuch (ISO/DIS 12957-2:2023)
Géosynthétiques - Détermination des caractéristiques de frottement - Partie 2: Essai sur
plan incliné (ISO/DIS 12957-2:2023)
Ta slovenski standard je istoveten z: prEN ISO 12957-2
ICS:
59.080.70 Geotekstilije Geotextiles
oSIST prEN ISO 12957-2:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN ISO 12957-2:2023
oSIST prEN ISO 12957-2:2023
DRAFT INTERNATIONAL STANDARD
ISO/DIS 12957-2
ISO/TC 221 Secretariat: BSI
Voting begins on: Voting terminates on:
2023-09-07 2023-11-30
Geosynthetics — Determination of friction
characteristics —
Part 2:
Inclined plane test
Géosynthétiques — Détermination des caractéristiques de frottement —
Partie 2: Essai sur plan incliné
ICS: 59.080.70
This document is circulated as received from the committee secretariat.
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ISO/DIS 12957-2:2023(E)
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oSIST prEN ISO 12957-2:2023
ISO/DIS 12957-2:2023(E)
DRAFT INTERNATIONAL STANDARD
ISO/DIS 12957-2
ISO/TC 221 Secretariat: BSI
Voting begins on: Voting terminates on:

Geosynthetics — Determination of friction
characteristics —
Part 2:
Inclined plane test
Géosynthétiques — Détermination des caractéristiques de frottement —
Partie 2: Essai sur plan incliné
ICS: 59.080.70
This document is circulated as received from the committee secretariat.
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
© ISO 2023
ISO/CEN PARALLEL PROCESSING
THEREFORE SUBJECT TO CHANGE AND MAY
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NATIONAL REGULATIONS.
Website: www.iso.org ISO/DIS 12957-2:2023(E)
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ii
PROVIDE SUPPORTING DOCUMENTATION. © ISO 2023

oSIST prEN ISO 12957-2:2023
ISO/DIS 12957-2:2023(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Test specimens . 2
5.1 Sampling and preparation of test specimen . 2
5.2 Number and dimensions of test specimens . 2
6 Conditioning . 2
7 Apparatus . 3
7.1 General . 3
7.2 Rigid base apparatus (see Figures 1 and 2) . 3
7.2.1 Rigid base. 3
7.2.2 Upper soil box (see Figure 4) . 5
7.3 Soil filled base apparatus (see Figure 3) . 6
7.3.1 Lower soil box . 6
7.3.2 Upper soil box (see Figure 4) . 6
7.4 Application of the normal force (for both types of apparatus). 8
7.5 Soil . 8
7.6 Calibration of the apparatus . . 9
8 Procedure .9
9 Calculations .10
9.1 Apparatus with a roller supported upper box . . 10
9.2 Apparatus with an upper box not supported on rollers . 10
10 Test Report .11
Bibliography .13
iii
oSIST prEN ISO 12957-2:2023
ISO/DIS 12957-2:2023(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
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This document was prepared by Technical Committee ISO/TC 221 Geosynthetics.
This fourth edition cancels and replaces the third edition (ISO 12957-2:2005) which has been technically
revised.
The main changes are as follows:
— minor modifications notably in the terms and definitions.
A list of all parts in the ISO 12957 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
oSIST prEN ISO 12957-2:2023
DRAFT INTERNATIONAL STANDARD ISO/DIS 12957-2:2023(E)
Geosynthetics — Determination of friction
characteristics —
Part 2:
Inclined plane test
1 Scope
This document describes a method to determine the friction characteristics of geosynthetics
(geotextiles and geotextile-related products, geosynthetic barriers), in contact with soils, or between
another geosynthetic, at low normal stress, using an inclining plane apparatus.
This test method is primarily intended as a performance test to be used with site specific soils but is
also used as an index test with standard sand. It is also possible to measure the displacement of the
interface over time (creep phenomenon) without necessarily reaching the slippage failure.
Test data obtained for geogrids tested with a rigid support are not necessarily realistic as the results
depend on the friction support.
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 554, Standard atmospheres for conditioning and/or testing — Specifications
ISO 6344-2, Coated abrasives – Grain size analysis – Part 2: Determination of grain size distribution of
macrogrits P 12 to P 220
ISO 9862, Geotextiles – Sampling and preparation of test specimens
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 10318-1 and the following
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 https:// www .electropedia .org/
3.1
normal stress
(σ )
n,o
normal force (N) divided by the area of the specimen, in kilopascals (kPa)
Note 1 to entry: σ indicates the normal stress with the table in horizontal position; σ indicates the calculated
n,o n,β
normal stress at slippage failure with angle of slipping (β).
oSIST prEN ISO 12957-2:2023
ISO/DIS 12957-2:2023(E)
3.2
angle of friction
(φ )
gp
angle of friction between geosynthetic and soil, in degrees, defined as the average of the values recorded
in the test
Note 1 to entry: The angle of friction is expressed in degrees (°).
3.3
angle of slipping
(β)
Angle at which the box’s displacement attains 50 mm
Note 1 to entry: The angle of slipping is expressed in degrees (°).
4 Principle
The angle of friction for the soil/geosynthetic system is determined by measuring the angle at which
a soil fill
...