oSIST prEN ISO 22476-9:2014

Ground investigation and testing - Field testing - Part 9: Field vane test

This standard covers the field vane test used in cohesive soils for the determination of the undrained peak and remoulded shear strength and the sensitivity of the soil. The Field Vane Test is used to determine undrained shear strength of cohesive soils, by pushing a rectangular vane body into cohesive soil and rotating it. During rotation the torque and rotation are measured. From the measured torque and the dimensions of the vane the undrained shear strength can be derived. With this test the remoulded strength can also be measured.

Geotechnische Erkundung und Untersuchung - Felduntersuchungen - Teil 9: Flügelscherversuch

Diese Europäische Norm legt Anforderungen an Baugrunduntersuchungen mit dem Flügelscherversuch im Rahmen der geotechnischen Untersuchungen nach EN 1997 2 fest.
Diese Europäische Norm behandelt den Flügelscherversuch für bindige Böden zur Bestimmung der maximalen undränierten Scherfestigkeit, der gestörten Scherfestigkeit und der Sensitivität des Bodens.

Reconnaissance et essais géotechniques - Essais en place - Partie 9: Essai au scissomètre de chantier

Geotehnično preiskovanje in preskušanje - Preskušanje na terenu - 9. del: Preskus s terensko krilno sondo

General Information

• Status: Not Published
• Public Enquiry End Date: 29-May-2014
• ICS: 93.020 - Earthworks. Excavations. Foundation construction. Underground works
• Technical Committee: KON.007 - Geotechnics
• Current Stage: 98 - Abandoned project (Adopted Project)
• Start Date: 11-May-2016
• Due Date: 16-May-2016
• Completion Date: 11-May-2016
• Ref Project: prEN ISO 22476-9 - Ground investigation and testing - Field testing - Part 9: Field vane test

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN ISO 22476-9:2014
01-maj-2014
*HRWHKQLþQRSUHLVNRYDQMHLQSUHVNXãDQMH3UHVNXãDQMHQDWHUHQXGHO3UHVNXV
VWHUHQVNRNULOQRVRQGR
Ground investigation and testing - Field testing - Part 9: Field vane test
Geotechnische Erkundung und Untersuchung - Felduntersuchungen - Teil 9:
Flügelscherversuch
Reconnaissance et essais géotechniques - Essais en place - Partie 9: Essai au
scissomètre de chantier
Ta slovenski standard je istoveten z: prEN ISO 22476-9
ICS:
93.020 Zemeljska dela. Izkopavanja. Earthworks. Excavations.
Gradnja temeljev. Dela pod Foundation construction.
zemljo Underground works
oSIST prEN ISO 22476-9:2014 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 22476-9:2014

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oSIST prEN ISO 22476-9:2014
DRAFT INTERNATIONAL STANDARD
ISO/DIS 22476-9
ISO/TC 182/SC 1 Secretariat: DIN
Voting begins on: Voting terminates on:
2014-02-27 2014-07-27
Ground investigation and testing — Field testing —
Part 9:
Field vane test
Reconnaissance et essais géotechniques — Essais en place —
Partie 9: Essai au scissomètre de chantier
ICS: 93.020
ISO/CEN PARALLEL PROCESSING
This draft has been developed within the European Committee for Standardization
(CEN), and processed under the CEN lead mode of collaboration as defined in the
Vienna Agreement.
This draft is hereby submitted to the ISO member bodies and to the CEN member
bodies for a parallel five month enquiry.
Should this draft be accepted, a final draft, established on the basis of comments
received, will be submitted to a parallel two-month approval vote in ISO and
THIS DOCUMENT IS A DRAFT CIRCULATED
formal vote in CEN.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
To expedite distribution, this document is circulated as received from the
IN ADDITION TO THEIR EVALUATION AS
committee secretariat. ISO Central Secretariat work of editing and text
BEING ACCEPTABLE FOR INDUSTRIAL,
composition will be undertaken at publication stage.
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 22476-9:2014(E)
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. ISO 2014

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oSIST prEN ISO 22476-9:2014
ISO/DIS 22476-9:2014(E)

Copyright notice
This ISO document is a Draft International Standard and is copyright-protected by ISO. Except as
permitted under the applicable laws of the user’s country, neither this ISO draft nor any extract
from it may be reproduced, stored in a retrieval system or transmitted in any form or by any means,
electronic, photocopying, recording or otherwise, without prior written permission being secured.
Requests for permission to reproduce should be addressed to either ISO at the address below or ISO’s
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Reproduction may be subject to royalty payments or a licensing agreement.
Violators may be prosecuted.
ii © ISO 2014 – All rights reserved

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oSIST prEN ISO 22476-9:2014
prEN 22476-9:2007.7 (E)
Figures
Figure 1 — Design of the vane . 7
Figure 2 — Assumed failure surface for standard vane . 12
Figure D.1 — Correction factors for τ . 19
v

Tables
Table 1 — Type of field vane test . 9
Table 2 — Application Classes . 11
Table C.1 — Control scheme for maintenance routines . 17
Table F.1 — Vane diameter suggestion . 21

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oSIST prEN ISO 22476-9:2014
prEN 22476-9:2007.7 (E)
Foreword
This document (FprEN 22476-9) has been prepared by Technical Committee CEN/TC 341 “Geotechnical
Investigation and Testing”, the secretariat of which is held by BSI.
This document is currently submitted to the UAP/FV Enquiry.
Introduction
The field vane test is used to determine undrained shear strength of cohesive soils, by pushing a rectangular
vane body into cohesive soil and rotating it. During rotation the torque and rotation are measured. This test
can measure the peak strength, the residual strength and the remoulded strength .From the measured
torque and the dimensions of the vane the undrained shear strength can be derived.
The tests are carried out in boreholes as well as with pushed in types or down hole types. The torque and
rotation are normally measured at ground level using extension rods; with downhole types the torque and
rotation are measured just above the vane body.
For field vane testing four methods are commonly used, depending on the soil conditions and the required
accuracy:
a) Downhole
The vane is inserted to the bottom of the borehole, the measurement takes place just above the vane
body.
b) Surface level, with cased extension rods
The vane is inserted to the bottom of the borehole, the measurement takes place at surface level, transfer
of torque by cased extension rods.
c) Surface level, with uncased extension rods with slip coupling
The vane is inserted to the bottom of the borehole, the measurement takes place at surface level, transfer
of torque by uncased extension rods with slip coupling.
d) Push in type
The vane is pushed in, the measurement takes place at surface level
This international standard is part of the range of international standards EN-ISO 22476 that deal with
geotechnical field testing:
 Part 1: Electrical cone penetration tests
 Part 2: Dynamic probing
 Part 3: Standard penetration test
 Part 4: Menard pressuremeter test
 Part 5: Flexible dilatometer test
 Part 6: Self-boring pressuremeter test (under preparation)
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oSIST prEN ISO 22476-9:2014
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 Part 7: Borehole jack test
 Part 8: Full displacement pressuremeter (under preparation)
 Part 9: Field vane test (under preparation)
1)
 Part 10: Weight sounding test (TS)
1)
 Part 11: Flat dilatometer test (TS)
 Part 12: Mechanical cone penetration test (CPTM)
 Part 13: Plate loading test (under preparation)
1 Scope
This European Standard specifies requirements for investigations of soil by the field vane test within the
scope of the geotechnical investigations according to EN 1997-2.
This European Standard covers the field vane test used in cohesive soils for the determination of the
undrained peak and remoulded shear strength and the sensitivity of the soil.
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 1997-2:2006, Eurocode 7: Geotechnical design – Part 2: Ground investigation and testing
ISO 10012, Measurment management systems – Requirements for measurement processes and measuring
equipment
3 Terms and definitions
For the purposes of this European Standard, the following terms and definitions apply.
3.1
field vane test
FVT
in situ test carried out with a rectangular vane, consisting of four plates fixed at 90º to each other, pushed
into the soil to the desired depth and rotated
3.2
maximum torque
T
max,u
torque required to obtain failure of undisturbed soil
3.3
maximum torque for remoulded conditions
T
max,r
torque required to to obtain failure of remoulded soil

1)
TS Technical Specification.
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oSIST prEN ISO 22476-9:2014
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3.4
test depth
depth at mid height of the vane
3.5
waiting time
time between reaching the test depth and first application of the torque to the vane
3.6
time to failure
time between the first application of the torque to the vane until the moment when maximum torque is
reached when measuring the undisturbed strength value
3.7
undisturbed shear strength
c
fv
undrained shear strength of undisturbed soil, derived from maximum torque
3.8
residual shear strength
c
res,fv
undrained shear strength after peak shear strength has been exceeded and a constant shear strength value
is measured or at a total rotation of 180°
3.9
remoulded shear strength
c
rem,fv
undrained shear strength after remoulding the soil
3.10
sensitivity according to field vane test
S
fv
sensitivity of the soil for disturbance
NOTE Sensitivity according to field vane test is the ratio of the undisturbed shear strength value to the remoulded
shear strength value.
3.11
undrained shear strength
definition needed?
4 Equipment
4.1 Vane
4.1.1 General vane dimensions
The vane shall consist of four rectangular plates fixed at 90º to each other, see Figure 1. The blades shall be
parallel with the extension rods and no significant distortion is allowed.
4.1.2 Dimensional limitations to minimise the effect of rod friction
The shape shall still be essentially rectangular with an H/D ratio of 2. Any deviation from the rectangular
shape shall be accounted for in the evaluation.
NOTE For practical reasons, uncased vanes often have slightly tapered lower ends of the blades. Some equipment
using uncased extension rods and a slip coupling to separate the rod friction from the torque on the vane are designed
with slightly tapered blades in order to disengage the slip coupling during the pushing stroke.
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Key
H Height of the vane
D Diameter of the vane
s Blade thickness
d Diameter of the rod
Figure 1 — Design of the vane
The relation between the height H and the diameter D of the vane shall be 2,0.
NOTE For standard vanes commonly used dimensions are:
 a maximum vane size D × H of 100 mm × 200 mm for soils with low to extremely low undrained shear strength
according to EN-ISO 14688-2,
 a minimum vane size D × H of 40 mm × 80 mm for soils with medium to high undrained shear strength according to
EN-ISO 14688-2,
 a minimum vane size D × H of 33 mm x 66 mm for soils with very high to extremely high undrained shear strength
according to EN-ISO 14688-2.
The blade thickness s shall not exceed 3,0 mm but shall not be less than 0,8 mm. In clays with S > 30 the
fv
blade thickness should not exceed 2,0 mm to minimise the disturbance of the soil during pushing the vane
into the soil.
The area ratio of the blades R should not be less than 12 %.
a
2
8h ⋅ (D − d )+ π ⋅d
R = ×100% (1)
a
2
π ⋅D
where:
R is the area ratio, in %;
a
h is the height of the vane, in mm; h = 2 D;
D is the diameter of the vane, in mm;
d is the diameter of the vane shaft, in mm.
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The diameter of the vane shaft, as well as possible welding seams in the centre of the vane shall be small
enough to avoid disturbing effects to the measured shear strength value.
NOTE In some easily disturbed soils and in organic soils, the actual size of the vane may affect the results.
If the vane is fitted with a protective casing, the length of the protrusion at the test shall be at least 5 times
the diameter of the vane.
The diameter of the vane shaft close to the vane should be less than 16 mm in sensitive soils. However,
vane shaft shall be of such rigidity that it does not twist significantly under full load conditions. In very stiff
clays and clay till, the diameter of the vane shaft above the vane may be 20 mm.
The vane shall be fitted with a device to separate the torque of the vane from any significant friction torque
along the extension rods. A casing, slip coupling or downhole torque sensor can be used.
4.2 Extension rods
Extension rods shall be used if the application of torque is at ground surface.
Extension rods shall have a diameter and torsional stiffness large enough to transmit the torque generated
during the test to the vane
The rods shall be straight. The eccentricity of the threads at the rod joints shall be less than 0,1 mm. Then
maximum permitted bending for rods or for two jointed rods is 2 mm over each 1 m of length, measured as
height of arch.
If casing tubes are used friction along the rods shall be minimised. The inner diameter of the tubes should be
large enough. For application class 2 the friction along the rods shall be measured at zero load just before
starting to rotate the vane.
4.3 Equipment for rotation and recording instrument
The equipment for rotation of the vane shall be designed to rotate at a given and constant rate, or be hand-
rotated in application class 4.
The recording instrument shall be designed to obtain the torque with accuracy compatible with the
application class in table 1.
Automatic recording is recommended. For interpretation of the test results a graph of the measured torque
versus the rotation angle should be made if possible.
The measuring range for the necessary measurements of the angle of rotation should be 360º, with a
resolution of 1º.
NOTE In many measuring systems, the registered rotation is the sum of the deformation in the measuring device,
(often some kind of spring), the twist in the extension rods and the rotation of the vane. This is sufficient for evaluation of
the mode of failure and identification of the maximum torque.
5 Test procedure
5.1 Selection and type of field vane test
The type of field vane test shall be chosen from table 1.
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Table 1 — Type of field vane test
Test Measurement Torque transfer Torque and rotation
registration
FVT Continuous downhole measurement No transfer Torque – real rotation
a of torque versus rotation
FVT Continuous uphole measurement of Transfer of torque by cased Torque – apparent
b torque versus rotation extension rods rotation
FVT Continuous uphole measurement of Transfer of torque by uncased Torque – apparent
c torque versus rotation extension rods with slip coupling rotation
FVT Uphole measurement of maximum Transfer of torque by uncased Maximum torque
d torque extension rods without slip coupling

5.2 Predrilling and pushing down the vane
With dry crust, fill or a stiff layer overlying a softer layer predrilling may be necessary to avoid the stiff soil
sticking to the vane or damage to the equipment.
If using an outer system with a casing protecting the vane, the water pressure in the casing system shall be
the same as that in the soil at the test level.
The vane shall be pushed straight down, if possible without use of blows or vibration. The pushing rate shall
be constant and not exceed 20 mm/s.
In stiff clays, silts and in clay till driving may be needed to get the vane to the desired depth.
The distance between investigation points shall be at least 2,0 m in plan in case of test depths greater than
5 m.
The first test shall normally be conducted at a depth of at least 0,5 m below the ground surface or at a depth
of at least 5 times the diameter of a predrilled hole below its base.
The minimum vertical distance for two tests conducted in the same borehole shall be at least 0,5 m.
NOTE In clay till, where the vane often cannot be pushed or driven 0.5 m into the soil without risk of considerable
damage, the minimum allowable test depth below the ground surface or base of a hole is. The minimum vertical distance
between two tests in the same borehole is then 2 times the vane height or 0.2 m whichever is the largest.
5.3 Vane shear test
In application classes 1 and 2, the time from the moment when the desired test depth has been reached to
the beginning of the vane test (waiting time) shall be at least 2 min and no more than 5 min.
The vane shall be loaded by application of torque in such a way that failure of the soil occurs in undrained
conditions. The vane shall be rotated at a constant rate.
NOTE The application of torque must not be too fast since the measured maximum torque is also sensitive to the
time to failure.
A guiding value for the rotating rate of the vane to fulfil the criteria given above in cohesive soils is that the
maximum torque is reached within 2 to 4 minutes. This time relates to the time after application of torque to
the vane itself, e.g after any slip coupling has been engaged.
The test shall be run in such a way that any significant skin friction along the rods can be separated.
In application classes 1, 2 and 3 hammering is not allowed.
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5.4 Possible determination of sensitivity
After failure has occurred and the maximum torque has been recorded, the vane may be rotated rapidly at
least ten turns in order to remould the soil at the failure surface, after which a new test is performed
immediately according to the instructions above. In case of continuous torque versus rotation measurement,
the remoulded value may be established upon reaching a constant torque value or ten turns whichever is
earlier. The constant value of the torque at the remoulded state is recorded.
5.5 Selection of equipment and procedures
The required accuracy is meant to be a function of what the results are to be used for. Application classes
have been developed to give guidance on selecting type of field vane test and required accuracy. The
application class specifies the type of cone penetrometer to be used and suggested use of test results for
given soil profiles. The use of test results is stated in terms of profiling, material identification and definition of
soil parameters.
Application class 1 for very special purposes (for example to measure stiffness and / or if requiring
high accuracy in extremely soft soils)
Application class 2 for an accurate value of undrained shear strength of soft to very soft soils
Application class 3 for stiffer soils
Application class 4 for very stiff soils where the equipment cannot be pushed
Equipment and procedures shall be selected according to the required application class given in table 2.
The reading interval depends on the application class in table 2.
Agreement must be achieved on test with peak undrained shear strength only or on test with peak and
remoulded undra
...