qwewqeqweASTM 187 – 16
Standard Test Method for Amount of Water Required for Normal Consistency of Hydraulic Cement Paste
SCOPE
This test method covers the determination of the normal consistency of hydraulic cement.
The values stated in SI units are to be regarded as standard. No other units of measurement are included in this
standard.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appropriate safety and health practices and determine the
applicability of regulatory limitations prior to use. See 1.4 for a specific warning statement.
Warning—Fresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue
upon prolonged exposure. The use of gloves, protective clothing, and eye protection is recommended. Wash
contact area with copious amounts of water after contact. Wash eyes for a minimum of 15 min. Avoid exposure of
the body to clothing saturated with the liquid phase of the unhardened material. Remove contaminated clothing
immediately after exposure.
This test method is intended to be used to determine the amount of water required to prepare hydraulic cement
pastes with normal consistency, as required for certain standard tests.
APPARATUS
Reference Masses and Devices for Determining Mass, conforming to the requirements of Specification C1005. The
devices for determining mass shall be evaluated for precision and bias at a total load of 1000 g.
Glass Graduates, 200 or 250-mL capacity, and
conforming to the requirements of Specification C1005.
Vicat Apparatus - consist of a frame A (Fig. 1) bearing a
movable rod B, weighing 300 g, one end C, the plunger
end, being 10 mm in diameter for a distance of at least
50 mm, and the other end having a removable needle
D, 1 mm in diameter and 50 mm in length. The rod B is
reversible, and can be held in any desired position by a
set screw E, and has an adjustable indicator F, which
moves over a scale (graduated in millimeters) attached
to the frame A.
The paste is held in a rigid conical ring G, resting on a
plane non-absorptive square base plate H, about 100
mm on each side. The rod B shall be made of stainless
steel having a hardness of not less than 35 HRC, and
shall be straight with the plunger end which is
perpendicular to the rod axis. The ring shall be made of
a non-corroding, nonabsorbent material, and shall have
an inside diameter of 70 mm at the base and 60 mm at
the top, and a height of 40 mm.
Flat Trowel, having a sharpened straight-edged steel blade 100 to 150 mm in length.
Temperature and Humidity
The temperature of the air and mixing water shall conform to the requirements of Specification C511.
The relative humidity of the laboratory shall conform to the requirements of Specification C511.
Procedure
Preparation of Cement Paste—Mix 650 g of cement with a measured quantity of water following the procedure
prescribed in the Procedure for Mixing Pastes of Practice C305. The water shall conform to the numerical limits of
Specification D1193 for Type III or Type IV grade of reagent water.
Molding Test Specimen—quickly form the cement paste into the approximate shape of a ball with gloved hands.
Then toss six times through a free path of about 150 mm from one hand to another so as to produce a nearly
spherical mass that may be easily inserted into the Vicat ring with a minimum amount of additional manipulation.
Press the ball, resting in the palm of one hand, into the larger end of the conical ring G, Fig. 1, held in the other
hand, completely filling the ring with paste.
Remove the excess at the larger end by a single movement of the palm of the hand. Place the ring on its larger end
on the base plate H, and slice off the excess paste at the smaller end at the top of the ring by a single oblique
stroke of a sharp-edged trowel held at a slight angle with the top of the ring, and smooth the top, if necessary,
with a few light touches of the pointed end of the trowel. During these operations of cutting and smoothing, take
care not to compress the paste.
Consistency Determination—Center the paste confined in the ring, resting on the plate, under the rod B, Fig. 1,
the plunger end C of which shall be brought in contact with the surface of the paste, and tighten the set-screw E.
Then set the movable indicator F to the upper zero mark of the scale, or take an initial reading, and release the rod
immediately. Release the rod at a time not exceeding 30 s after completion of mixing. The apparatus shall be free
of all vibrations during the test. The paste shall be of normal consistency when the rod settles to a point 10 6 1 mm
below the original surface in 30 s after being released. Make trial pastes with varying percentages of water until
the normal consistency is obtained. Make each trial with fresh cement.
Calculation - Calculate the amount of water required for normal consistency as the mass of water divided by the
mass of dry cement, expressed as a percentage. Calculate the mass ratio to the nearest 0.1 % and report the mass
ratio to the nearest 0.5 %.
Precision and Bias – The single operator-instrument precision has been found to be 0.25 (1S), and the
multilaboratory precision has been found to be 0.35 (1S) as defined in Practice E177; therefore, the results of two
properly conducted tests by the same operator in a laboratory should agree within 0.7 percentage point, and test
results between two laboratories should agree with 1.0 percentage point 95 % of the time.
