ISO 1920-2:2016

INTERNATIONAL ISO
STANDARD 1920-2
Second edition
2016-11-01
Testing of concrete —
Part 2:
Properties of fresh concrete
Essais du béton —
Partie 2: Caractéristiques du béton frais
Reference number
©
ISO 2016
© ISO 2016, Published in Switzerland
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ii © ISO 2016 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Determination of consistence . 2
4.1 General . 2
4.2 Sampling . 2
4.3 Slump test . 2
4.3.1 Principle . 2
4.3.2 Apparatus . 2
4.3.3 Procedure . 3
4.3.4 Test result . . 4
4.3.5 Test report . 5
4.4 Vebe test . 5
4.4.1 Principle . 5
4.4.2 Apparatus . 5
4.4.3 Procedure . 8
4.4.4 Test result . . 8
4.4.5 Test report . 9
4.5 Degree of compactability test . 9
4.5.1 Principle . 9
4.5.2 Apparatus . 9
4.5.3 Procedure .10
4.5.4 Test results .11
4.5.5 Test report .11
4.6 Flow-table test .12
4.6.1 Principle .12
4.6.2 Apparatus .12
4.6.3 Procedure .14
4.6.4 Test results .15
4.6.5 Test report .15
4.7 Slump-flow test .16
4.7.1 General.16
4.7.2 Principle .16
4.7.3 Apparatus .16
4.7.4 Procedure .17
4.7.5 Test report .18
5 Determination of fresh density .19
5.1 Principle .19
5.2 Apparatus .19
5.3 Sampling .20
5.4 Procedure .20
5.4.1 Mass of the container .20
5.4.2 Filling the container .20
5.4.3 Compacting the concrete .20
5.4.4 Surface levelling . . .21
5.4.5 Determining the mass and volume of the container .21
5.5 Test result .21
5.6 Test report .21
6 Determination of air content .22
6.1 General .22
6.2 Sampling .22
6.3 Filling the container and compacting the concrete .22
6.3.1 Means of compaction .22
6.3.2 Filling the container .22
6.3.3 Compacting the concrete .23
6.4 Pressure-gauge method .23
6.4.1 Principle .23
6.4.2 Apparatus .23
6.4.3 Filling the container and compacting the concrete .25
6.4.4 Procedure .25
6.5 Water-column method .25
6.5.1 Principle .25
6.5.2 Apparatus .25
6.5.3 Filling the container and compacting the concrete .27
6.5.4 Procedure .27
6.6 Calculations and expression of results .28
6.6.1 Air content of the sample tested .28
6.6.2 Air content of the mortar fraction .28
6.7 Test report .28
7 Test report .29
Annex A (informative) Precision — Data for the density measurements .30
Annex B (normative) Calibration of the container for the density test .31
Annex C (informative) Additional calculations for the density test .32
Annex D (informative) Precision — Water-column method .33
Annex E (normative) Calibration of apparatus — Pressure-gauge method .34
Annex F (normative) Calibration of apparatus — Water-column method .36
Annex G (normative) Aggregate corrector factor — Pressure-gauge method .39
Annex H (normative) Aggregate correction factor — Water-column method .41
Annex I (informative) Examples of test reports and worksheets .43
Bibliography .57
iv © ISO 2016 – All rights reserved

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 on 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 the following URL: www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 71, Concrete, reinforced concrete and pre-
stressed concrete, Subcommittee SC 1, Test methods for concrete.
This second edition cancels and replaces the first edition (ISO 1920-2:2005), which has been technically
revised with the following changes:
a) 4.3.5, list a) has been updated;
b) 4.7.3.3, the required minimum dimensions 800 mm × 800 mm have been added;
a
c) Figure 11, footnote was added;
d) 6.4.4, Note was added;
e) Bibliography list has been updated.
A list of all parts in the ISO 1920 series can be found on the ISO website.
Introduction
International Standards are widely adopted at the regional or national level and applied by
manufacturers, trade organizations, purchasers, consumers, testing laboratories, authorities and other
interested parties. Since these documents generally reflect the best experience of industry, researchers,
consumers and regulators worldwide and cover common needs in a variety of countries, they constitute
one of the important bases for the removal of technical barriers to trade. However, full adoption may
not be practicable in all cases for reasons, such as regional or national security, protection of human
health or safety, or protection of the environment, or because of fundamental climatic, geographical or
technological problems. As a consequence, the corresponding technical deviations to ISO standards are
permitted where required by national or regional legislation or industry convention when adopting an
International Standard.
Where such national deviations are required, it is important that they are clearly identified and the
reasons for the deviations stated. Depending of on the method of adoption of the International Standard,
the deviations will be noted in the national introduction, in the preface or foreword (for small numbers)
or as a national annex (for large numbers). See ISO/IEC Guide 21-1 for more information.
ISO/TC 71/SC 1 has identified those items in this document that may be the subject of national or
regional deviations. The items are indicated in the text by the phrase “…except where the national
annex to this document requires…”.
vi © ISO 2016 – All rights reserved

INTERNATIONAL STANDARD ISO 1920-2:2016(E)
Testing of concrete —
Part 2:
Properties of fresh concrete
Caution — When cement is mixed with water, alkali is released. When sampling, prevent skin
contact with wet cement or concrete by wearing suitable protective clothing (gloves, footwear,
safety glasses). If wet cement or concrete enters the eye, immediately wash it out thoroughly
with clean water and seek medical treatment without delay. Wash wet concrete off the skin
immediately.
Caution — The use of vibrating equipment, such as vibration tables, can cause damage to joints
and loss of sensation due to nerve damage. Moulds, density containers, etc. should be clamped to
the table and not held in position using one’s hands while they are being vibrated.
1 Scope
This document specifies procedures for testing fresh concrete. It specifies the following test methods:
determination of consistence (slump test, Vebe test, degree of compactability, flow-table test for
high-fluidity concrete, and the slump-flow test), determination of fresh density and determination of
air content by the pressure-gauge method and by the water-column method.
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 1101, Geometrical product specifications (GPS) — Geometrical tolerancing — Tolerances of form,
orientation, location and run-out
ISO 1920-1, Testing of concrete — Part 1: Sampling of fresh concrete
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
3.1
fresh density
mass of a quantity of fully compacted fresh concrete divided by its volume
Note 1 to entry: The fresh density is expressed in kilograms per cubic metre.
4 Determination of consistence
4.1 General
The consistence of the concrete is determined by one of the methods described below:
— slump test (see 4.3);
— Vebe test (see 4.4);
— degree of compactability (see 4.5);
— flow-table test (see 4.6);
— slump-flow test for high-fluidity concrete (see 4.7).
These methods are not applicable to foamed concrete, no-fines concrete, or where the maximum
aggregate size exceeds 40 mm.
4.2 Sampling
Samples for the tests shall be obtained in accordance with ISO 1920-1. Each sample shall be remixed
before carrying out the tests.
4.3 Slump test
4.3.1 Principle
The fresh concrete is compacted into a mould in the shape of a frustum of a cone. When the cone is
withdrawn upwards, the distance the concrete has slumped provides a measure of the consistence of
the concrete.
The slump test is applicable to a range of consistence of concrete that corresponds to slumps of between
10 mm and 210 mm. Outside this range, the measurement of slump may be unsuitable and other
methods of determining the consistence should be considered.
If the slump continues to change over a period of 1 min after remoulding, this test is not suitable.
NOTE For high-fluidity concrete, the slump-flow test described in 4.7 is a more appropriate test.
4.3.2 Apparatus
Note the calibration requirements associated with each apparatus.
4.3.2.1 Mould, suitable of forming the test specimen, made of a metal not readily attacked by cement
paste and not thinner than 1,5 mm.
The mould may be made either with or without a seam. The interior of the mould shall be smooth and
free from projections such as protruding rivets and shall be free from dents. The mould shall be in the
form of hollow frustum of a cone and shall have the following internal dimensions:
— diameter of base:   200 mm ± 2 mm;
— diameter of top:    100 mm ± 2 mm;
— height:             300 mm ± 2 mm.
The base and the top shall be open and parallel to each other and at right angles to the axis of the cone.
The mould shall be provided, on the upper portion, with two handles at two-thirds of the height, and at
the bottom with fixing clamps or foot pieces to hold it steady. A mould that can be clamped to the base
2 © ISO 2016 – All rights reserved

is acceptable, provided the clamping arrangement can be fully released without movement of the mould
or interference with the slumping concrete.
The mould shall be visually checked prior to each use to assure that it is clean and is not damaged or
dented. The cone shall be checked annually to ensure that its dimensions and conditions remain within
tolerances.
4.3.2.2 Tamping rod, straight, made of steel, having a circular cross-section with a diameter of
16 mm ± 1 mm, 600 mm ± 5 mm in length, and with rounded ends. The rod may be extended with a
handle of plastic conduit, provided that the overall length does not exceed 1 000 mm.
The tamping rod shall be checked annually to ensure that its dimensions and conditions remain within
tolerances.
4.3.2.3 Funnel (optional), made of a non-absorbent material not readily attacked by cement paste.
The funnel shall consist of two co-axial conical frustums having a common diameter of 100 mm, the
ends being of greater diameter, one frustum to act as a filling funnel and the other as a collar to enable
the funnel to be located on the outer surface of the mould.
The funnel shall be checked annually to ensure that its dimensions and conditions remain within
tolerances.
4.3.2.4 Rule, graduated from 0 mm to 300 mm, at intervals not exceeding 5 mm, with the zero point
being at the extreme end of the rule.
4.3.2.5 Base plate/surface, rigid, flat, non-absorbent and smooth plate or other surface on which to
place the mould.
4.3.2.6 Shovel, with a square blade.
4.3.2.7 Remixing tray, of rigid construction and made from a non-absorbent material not readily
attacked by cement paste.
It shall be of appropriate dimensions such that the concrete can be thoroughly remixed, using the
square-bladed shovel.
4.3.2.8 Scoop, with a width of approximately 100 mm.
4.3.2.9 Timer or other similar timing device, to allow time measurement to 1 s.
The watch shall be properly calibrated at the time of test.
4.3.2.10 Moist cloth.
4.3.3 Procedure
Dampen the mould and the base plate. Wipe any excessive water from the surfaces, using an absorbent
cloth. Place the mould on the horizontal base plate/surface. During filling, clamp or hold the mould
firmly in place by standing on the two foot pieces.
Immediately after obtaining the sample in accordance with 4.2, fill the mould in three layers, each
approximately one-third of the height of the mould when compacted. When adding the concrete, ensure
that it is distributed symmetrically around the mould. Tamp each layer with 25 strokes of the tamping
rod. Uniformly distribute the strokes over the cross-section of each layer. For the bottom layer, this will
necessitate inclining the rod slightly and positioning approximately half the strokes spirally toward
the centre. Tamp the second layer and the top layer each throughout its depth, so that the strokes just
penetrate into the underlying layer. In filling and tamping the top layer, heap the concrete above the
mould before tamping is started.
When the specified tamping procedure could cause segregation of the sample, the number of tamping
strokes may be reduced to an extent that segregation can be avoided.
If the tamping operation of the top layer results in subsidence of the concrete below the top edge of the
mould, add more concrete to keep an excess above the top of the mould at all times. Also ensure that the
addition of concrete to the top layer does not provide extra compaction of the concrete. After the top
layer has been tamped, scrape off the surface of the concrete level with the top of the mould by means
of a sawing and rolling motion of the tamping rod.
Remove spilled concrete from the base plate/surface. Remove the mould in 3,5 s ± 1,5 s by a steady
upward lift with no lateral or torsional motion being imparted to the concrete. The lifting time may be
shortened when required by the national annex.
The entire operation from the start of the filling to the removal of the mould shall be carried out without
interruption and shall be completed within 180 s.
Immediately after removal of the mould, determine the slump, h, by measuring the difference between
the height of the mould and that of the highest point of the slumped test sample (see Figure 1), except
where the national annex to this document requires the measurement of the difference between the
height of the mould and the centre point or the average height of the slumped concrete. Measure to the
nearest 10 mm, except where the national annex to this document requires the measurement to the
nearest 5 mm.
4.3.4 Test result
The test is valid only if it yields a true slump, this being a slump in which the concrete remains
substantially intact and symmetrical as shown in Figure 2 a). If a specimen shears, as shown in
Figure 2 b), take another sample and repeat the procedure.
Record the true slump, h, as shown in Figure 1 to the nearest 10 mm, or 5 mm when required by the
national annex.
If two consecutive tests show a portion of the concrete shearing off from the mass of the test specimen,
report the test as being invalid as the concrete lacks the necessary plasticity and cohesiveness for the
slump test to be suitable.
Figure 1 — Slump measurement
4 © ISO 2016 – All rights reserved

a) True slump     b) Shear
Figure 2 — Forms of slump
4.3.5 Test report
In addition to the information required in Clause 7, the test report shall include the following:
a) the slump, measured to a nearest 10 mm (or 5 mm when required by the national annex), and its
measuring point: highest, centre or average, if there is a true slump, or;
b) a notation that the test gave a sheared slump;
c) identification of specimen;
d) time and date of testing.
4.4 Vebe test
4.4.1 Principle
The fresh concrete is compacted into a slump mould. The mould is lifted clear of the concrete and a
transparent disc is swung over the top of the concrete and carefully lowered until it comes in contact
with the concrete. The slump of the concrete is recorded. The vibrating table is started and the time
taken for the lower surface of the transparent disc to be fully in contact with concrete is measured.
If the Vebe time is less than 5 s or more than 30 s, the use of this test method to determine consistence
may be unsuitable and other methods should be considered for this purpose.
4.4.2 Apparatus
Note the calibration requirements associated with each apparatus.
4.4.2.1 Consistometer (Vebe meter), consisting of the following items and as shown in Figure 3:
a) container (Figure 3, item 1), cylindrical in shape, having an internal diameter of 240 mm ± 5 mm
and a height of 200 mm ± 2 mm, and made of a metal not readily attacked by cement paste. The
thickness of the wall shall be 3 mm and that of the base, 7,5 mm.
The container shall be watertight and of sufficient rigidity to retain its shape under rough usage.
It shall be fitted with handles and protected from corrosion. The container shall be provided with
suitable foot pieces to enable it to be securely clamped to the top of the vibrating table (Figure 3,
item 7) by means of wing nuts (Figure 3, item 8).
b) mould (Figure 3, item 2), as described in 4.3.2.1, except that the fixing clamps or foot pieces are not
required.
The mould shall be visually checked prior to each use to assure that it is clean and is not damaged
or dented.
c) disc (Figure 3, item 3), transparent, horizontal, attached to a rod (Figure 3, item 9) that slides
vertically through a guide sleeve (Figure 3, item 5) mounted on a swivel arm (Figure 3, item 13)
and which can be fixed in position by a screw (Figure 3, item 15).
The swivel arm also supports a funnel (Figure 3, item 4), the bottom of which coincides with the
top of the conical mould when the latter is positioned concentrically in the container. The swivel
arm is located by a holder (Figure 3, item 12) and can be fixed in position by a set-screw (Figure 3,
item 6). When in the appropriate position, the axes of the rod and of the funnel shall be coincident
with the axis of the container.
The transparent disc shall be 230 mm ± 2 mm in diameter and 10 mm ± 2 mm in thickness. A weight
(Figure 3, item 14) placed directly above the disc shall be provided such that the moving assembly
consisting of the rod, the disc and the weight has a mass of 2 750g ± 50 g. The rod shall be provided
with a scale graduated to at least 5 mm intervals to record the slump of the concrete.
d) vibrating table (Figure 3, item 7), 380 mm ± 3 mm in length and 260 mm ± 3 mm in width,
supported on four rubber shock absorbers.
A vibrator unit (Figure 3, item 11), carried on a base (Figure 3, item 10) resting on three rubber
feet, shall be securely fixed beneath it. The vibrator shall operate at a frequency of 55 Hz ± 5,5 Hz
and the vertical amplitude of the vibration of the table with the empty container on top of it shall be
approximately 0,5 mm ± 0,02 mm.
The vibrating table shall be checked annually to ensure that the frequency and vertical amplitude
remain within tolerances.
All the elements of the vibration table shall be checked annually to ensure that their dimensions
remain within tolerances.
6 © ISO 2016 – All rights reserved

Key
1 container 9 rod
2 mould 10 base for vibrator
3 transparent disc 11 vibrator unit
4 funnel 12 holder
5 guide sleeve 13 swivel arm
6 set-screw 14 weight
7 vibrating table 15 screw
8 wing nuts
Figure 3 — Consistometer (Vebe meter)
4.4.2.2 Tamping rod, straight, made of steel or other suitable metal, of circular cross-section, having a
diameter of 16 mm ± 1 mm, 600 mm ± 5 mm in length, and with rounded ends.
4.4.2.3 Stopwatch or clock, capable of recording time to an accuracy of 0,5 s.
4.4.2.4 Remixing container, of rigid construction, made from a non-absorbent material not readily
attacked by cement paste.
4.4.2.5 Scoop, with a width of approximately 100 mm.
4.4.2.6 Moist cloth.
4.4.3 Procedure
Place the Vebe meter (consistometer) on a rigid horizontal base free from extraneous vibration and
shock. Make sure that the container (Figure 3, item 1) is firmly fixed to the vibrating table (Figure 3,
item 7) by means of the wing nuts (Figure 3, item 8). Dampen the mould (Figure 3, item 2) and place it
in the container. Swing the funnel (Figure 3, item 4) into position over the mould and lower the funnel
on the mould. Tighten the screw (Figure 3, item 6) so that the mould cannot rise from the bottom of the
container.
During the subsequent operations, ensure that the mould (Figure 3, item 2) does not rise or move until
it is raised and do not allow any concrete to fall into the container (Figure 3, item 1).
From the sample of concrete obtained in accordance with 4.2, immediately fill the mould in three
layers, each approximately one-third of the height of the mould when compacted. Tamp each layer with
25 strokes of the tamping rod. Uniformly distribute the strokes over the cross-section of each layer. For
the bottom layer, this will necessitate inclining the rod slightly and positioning approximately half the
strokes spirally toward the centre. Tamp the second layer and the top layer each throughout its depth,
so that the strokes just penetrate into the underlying layer. In filling and tamping the top layer, heap the
concrete above the mould before tamping is started.
If necessary, add further concrete to maintain an excess above the top of the mould throughout the
tamping operation. After the top layer has been tamped, loosen the screw (Figure 3, item 6), raise and
swing the funnel (Figure 3, item 4) through 90° and tighten the screw (Figure 3, item 6).
Scrape off the concrete level with the top of the mould with a sawing and rolling motion of the tamping
rod. Remove the mould (Figure 3, item 2) from the concrete by raising it carefully in a vertical direction,
using the handles. The operation of raising the mould shall be performed in 2 s to 5 s by a steady upward
lift with no lateral or torsional motion being imparted to the concrete.
If the concrete shears [as shown in Figure 4 b)], collapses [as shown in Figure 4 c)], or slumps to the
extent that it touches the wall of the container (Figure 3, item 1), this information shall be recorded.
If the concrete has not slumped into contact with the wall of the container (Figure 3, item 1) and a true
slump, as shown in Figure 4 a) has been obtained, the fact shall be recorded.
Swing the transparent disc (Figure 3, item 3) over the top of the concrete, tighten the screw (Figure 3,
item 6), loosen the screw (Figure 3, item 15) and very carefully lower the disc until it just comes in
contact with the concrete.
When the disc (Figure 3, item 3) just touches the highest point of the concrete without disturbing it,
tighten the screw (Figure 3, item 15). When there is a true slump, the value of the slump shall be read
from the scale (Figure 3, item 9) and the value recorded.
The screw (Figure 3, item 15) shall be loosened to allow the disc (Figure 3, item 3) to follow the concrete
as it settles under the subsequent vibration. Simultaneously, start the vibration of the table and the
timer. Observe through the transparent disc (Figure 3, item 3) how the concrete is being remoulded. As
soon as the lower surface of the disc is fully in contact with cement grout, stop the timer and switch off
the vibrating table. Record the time taken to the nearest second.
Complete the procedure within a period of 5 min from the start of filling.
The consistence of a concrete mix changes with time due to hydration of the cement and, possibly, loss
of moisture. Tests on different samples should, therefore, be carried out at a constant time interval
after mixing if strictly comparable results are to be obtained.
4.4.4 Test result
Record the time read from the stopwatch to the nearest second. This is the Vebe time expressing the
consistence of the concrete under test.
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a) True slump b) Shear c) Collapse
Figure 4 — Forms of slump
4.4.5 Test report
In addition to the information required in Clause 7, the test report shall include the following:
a) type of slump: true slump/collapse/shear;
b) when there is a true slump, the measured slump, to nearest 10 mm;
c) time from completion of mixing of the concrete until the time of removal of the mould;
d) vebe time, in seconds;
e) identification of specimen;
f) time and date of testing.
4.5 Degree of compactability test
4.5.1 Principle
The fresh concrete is carefully placed with a trowel in a container avoiding any compaction while
filling. When the container is full, the top surface is scraped off level with the top of the container. The
concrete is compacted and the distance from the surface of the compacted concrete to the upper edge
of the container is used to determine the degree of compactability.
If the degree of compactability is less than 1,04 or more than 1,46, the concrete has a consistence for
which the degree of compactability test is not suitable.
4.5.2 Apparatus
4.5.2.1 Container, with parallel sides and a general shape as shown in Figure 6, made of metal not
readily attacked by cement paste and having the following internal dimensions:
— base:      200 mm ± 2 mm × 200 mm ± 2 mm;
— height:   400 mm ± 2 mm;
— the thickness of the base and walls shall be at least 1,5 mm.
The bottom of the container may be perforated to facilitate emptying. A suitable plastic plate to cover
the bottom has then to be placed inside the container.
The dimensions and condition of the container shall be checked at the time of test to ensure that they
are within the tolerances.
4.5.2.2 Trowel, with a flat blade (see Figure 5), or equivalent, e.g. square-bladed shovel.
Dimensions in millimetres
Figure 5 — Trowel
4.5.2.3 Means of compacting the concrete, consisting of one of the following:
a) internal vibrator, with a minimum frequency of 120 Hz (7 200 cycles per minute). The diameter of
the vibrating head shall not exceed one-quarter of the smallest dimension of the container;
b) vibrating table, with a minimum frequency of 40 Hz (2 400 cycles per minute).
4.5.2.4 Remixing tray, of rigid construction, made from a non-absorbent material not readily attacked
by cement paste.
4.5.2.5 Straight edged scraper, having a length of greater than 200 mm.
4.5.2.6 Rule, having a length of greater than 400 mm, having 1 mm subdivisions along its entire length
with the zero point being at the extreme end of the rule.
4.5.2.7 Moist cloth.
4.5.3 Procedure
Clean the container and moisten the inner surfaces using a damp cloth.
Fill the container without tamping it, by tilting the trowel sideways from all four upper edges of the
container in turn. When the container is full, remove all concrete above the upper edges, using the
straight-edged scrapper with a sawing action, in such a way as to avoid any compaction.
Compact the concrete by means of a vibrating table (reference method) or by the use of an internal
vibrator, until no further reduction in volume is determinable. During compaction, avoid loss of concrete
through splashing or leakage.
10 © ISO 2016 – All rights reserved

After compaction, measure to the nearest millimetre, the distance between the surface of the compacted
concrete and the upper edge of the container at the middle of each side of the container. Determine the
mean value of the four measurements (see Figure 6).
a) Before compaction b) After compaction
Figure 6 — Concrete in container, before a) and after b) compaction
4.5.4 Test results
The degree of compactability is given by Formula (1):
h
c = (1)
hh−
where
c is the degree of compactability;
h is the internal height of the container;
h is the mean value, to the nearest millimetre, of the distance from the surface of the compacted
concrete to the upper edge of the container.
4.5.5 Test report
In addition to the information required in Clause 7, the test report shall include the following:
a) internal height of the container;
b) measurements of the distance from the top of the container to the top of the compacted concrete;
c) degree of compactability, expressed to nearest two decimal places.
4.6 Flow-table test
4.6.1 Principle
This test determines the consistence of fresh concrete by measuring the spread of concrete on a flat
plate subjected to jolting.
The flow test is applicable to a range of consistence of concrete that corresponds to flow values
between 340 mm and 620 mm. Outsi
...