AASHTO T 129-2017 Standard Method of Test for Amount of Water Required for Normal Consistency of Hydraulic Cement Paste.pdf

1、Standard Method of Test for Amount of Water Required for Normal Consistency of Hydraulic Cement Paste AASHTO Designation: T 129-14 Technical Section: 3a, Hydraulic Cement and Lime ASTM Designation: C187-111American Association of State Highway and Transportation Officials 444 North Capitol Street N.

2、W., Suite 249 Washington, D.C. 20001 TS-3a T 129-1 AASHTO Standard Method of Test for Amount of Water Required for Normal Consistency of Hydraulic Cement Paste AASHTO Designation: T 129-14 Technical Section: 3a, Hydraulic Cement and Lime ASTM Designation: C187-1111. SCOPE 1.1. This method covers det

3、ermination of the normal consistency of hydraulic cement. 1.2. UnitsThe values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3. This standard may involve hazardous materials, operations, and equipment. This standard does not purport

4、 to address all of the safety concerns associated with its use. It is the responsibility of the user of this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. WarningFresh hydraulic cementitious mixtures

5、are caustic and may cause chemical burns to skin and tissue on 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 satur

6、ated with the liquid phase of the unhardened material. Remove contaminated clothing immediately after exposure. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 201, Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage Tanks Used in the Testing of Hydraulic Cements and Concretes T 162, Mecha

7、nical Mixing of Hydraulic Cement Pastes and Mortars of Plastic Consistency 2.2. ASTM Standards: C219, Standard Terminology Relating to Hydraulic Cement C1005, Standard Specification for Reference Masses and Devices for Determining Mass and Volume for Use in the Physical Testing of Hydraulic Cements

8、D1193, Standard Specification for Reagent Water E177, Standard Practice for Use of the Terms Precision and Bias in ASTM Test Methods 3. TERMINOLOGY 3.1. Normal consistency is defined in ASTM C219. 2017 by the American Association of State Highway and Transportation Officials.All rights reserved. Dup

9、lication is a violation of applicable law.TS-3a T 129-2 AASHTO 4. SIGNIFICANCE AND USE 4.1. 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. 5. APPARATUS 5.1. Referenc

10、e Masses and Devices for Determining MassConforming to the requirements of ASTM C1005. The devices for determining mass shall be evaluated for precision and bias at a total load of 1000 g. 5.2. Glass Graduates200- or 250-mL capacity and conforming to the requirements of ASTM C1005. 5.3. Vicat Appara

11、tusShall consist of a frame (A) bearing a movable rod (B), weighing 300 g, with 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, can be held in any

12、 desired position by a set screw (E), and has an adjustable indicator (F) that 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 nonabsorptive square base plate (H) about 100 mm on each side. The rod (B) shall b

13、e made of stainless steel having a hardness of not less than 35 HRC (see Note 1) and shall be straight with the plunger end, which is perpendicular to the rod axis. The ring shall be made of a noncorroding, nonabsorbent material; shall have an inside diameter of 70 mm at the base and 60 mm at the to

14、p; and shall have a height of 40 mm. (See Figure 1.) In addition to the above, the Vicat apparatus shall conform to the requirements as indicated in Table 1. Note 1The requirement that the rod be made of stainless steel shall apply only to new Vicat apparatus or replacement rods and not to equipment

15、 in use that meets the other requirements of this standard. 5.4. Flat TrowelHaving a sharpened straight-edged steel blade 100 to 150 mm in length. 2017 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-3a T

16、129-3 AASHTO Figure 1Vicat Apparatus Table 1Vicat Apparatus Vicat Apparatus Weight of movable rod 300 0.5 g Diameter of plunger end of rod 10 0.05 mm Diameter of needle 1 0.05 mm Inside diameter of ring at bottom 70 3 mm Inside diameter of ring at top 60 3 mm Height of ring 40 1 mm Graduated scale T

17、he graduated scale, when compared with a standard scale accurate to within 0.1 mm at all points, shall not show a deviation at any point greater than 0.25 mm. 6. TEMPERATURE AND HUMIDITY 6.1. The temperature of the air and mixing water shall conform to the requirements of M 201. D DB BF FERemovable

18、Needle,1 mm by 50 mm,concealed in endof shaftEntire 50-mm lengthgraduated bymillimetersECCG GH HA A 2017 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-3a T 129-4 AASHTO 6.2. The relative humidity of the

19、laboratory shall conform to the requirements of M 201. 7. PROCEDURE 7.1. Preparation of Cement PasteMix 650 g of cement with a measured quantity of clean water following the procedure prescribed in Section 6 of T 162. The water shall conform to the numerical limits of ASTM D1193 for Type III or Type

20、 II grade of reagent water. 7.2. Molding Test SpecimenQuickly form the cement paste, prepared as described in Section 7.1, 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

21、 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), held in the other hand, completely filling the ring with paste. (See Figure 1.) Remove the excess at the la

22、rger 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; smooth the top,

23、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. 7.3. Consistency DeterminationCenter the paste confined in the ring, resting on the plate, under the rod (B) (see Figure 1), the plunger end

24、 (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 o

25、f 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 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 obtai

26、ned. Make each trial with fresh cement. 8. CALCULATION 8.1. 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 percent and report the mass ratio to the nearest 0.

27、5 percent. 9. PRECISION AND BIAS 9.1. 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 ASTM E177; therefore, the results of two properly conducted tests by the same operator in a laboratory should ag

28、ree within 0.7 percentage point, and test results between two laboratories should agree within 1.0 percentage point 95 percent of the time. 10. KEYWORDS 10.1. Consistency; normal consistency; Vicat needles. 2017 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.