1、Standard Practice for Sampling and Fabrication of 50-mm (2-in.) Cube Specimens Using Grout (Non-Shrink) or Mortar AASHTO Designation: R 64-151American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-3b R 64-1 AASHTO Standar
2、d Practice for Sampling and Fabrication of 50-mm (2-in.) Cube Specimens Using Grout (Non-Shrink) or Mortar AASHTO Designation: R 64-1511. SCOPE 1.1. This practice covers field sampling and fabrication and initial curing of 50-mm (2-in.) cube specimens of nonshrink grout or mortar materials, or both.
3、 1.2. The values stated in either inch-pound or SI units shall be regarded separately as standard. The inch-pound units are shown in parentheses. The values stated might not be exact equivalents; therefore, each system must be used independently of the other. Note 1“Unit weight” was the previous ter
4、minology used to describe the property determined by this practice, which is mass per unit volume. 1.3. The text of this practice references notes and footnotes that provide explanatory information. These notes and footnotes (excluding those in tables) shall not be considered as requirements of this
5、 practice. 1.4. 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. Wa
6、rningFresh hydraulic cementitious mixtures are caustic and may cause chemical burns to skin and tissue upon prolonged exposure. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standard: R 60, Sampling Freshly Mixed Concrete 3. TERMINOLOGY 3.1. Definitions of Terms Specific to This Standard: 3.1.1. plastic mixma
7、terial viscous enough that an indentation will be left in the surface of the grout after tamping. 3.1.2. fluid mixmaterial fluid enough that little or no indentation will be left in the surface after puddling. 4. SIGNIFICANCE AND USE This practice provides standardized requirements for sampling, fab
8、rication, and curing of 50-mm (2-in.) cube specimens of nonshrink grout and mortar materials. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-3b R 64-2 AASHTO 5. APPARATUS 5.1. Specimen Molds Includin
9、g Cover Plate(s)The 50-mm (2 in.) cube specimen molds shall be tight-fitting and made of brass or other suitable material. This material shall not be susceptible to attack by the cement mortar. The mold portion shall have not more than three cube compartments and shall be separable into not more tha
10、n two parts. The mold halves, when assembled, shall be positively held together. The working surface of the cover plate(s) shall be plane. The interior faces of the molds shall conform to the tolerances of Table 1. Table 1Permissible Variations of Specimen Molds Parameter 50-mm Cube Molds 2-in. Cube
11、 Molds New In Use New In Use Planeness of sides 0.025 mm 0.05 mm 0.001 in. 0.002 in. Distance between opposite sides 50 mm 0.13 mm 50 mm 0.50 mm 2 in. 0.005 in. 2 in. 0.02 in. Height of each compartment 50 mm + 0.25 mm to 0.13 mm 50 mm + 0.25 mm to 0.38 mm 2 in. + 0.01 in. to 0.005 in. 2 in. + 0.01
12、in. to 0.015 in. Angle between adjacent facesa90 0.5 90 0.5 90 0.5 90 0.5 aMeasured at points slightly removed from the intersection. Measured separately for each compartment between all the interior faces and the adjacent face and between interior faces and top and bottom planes of the mold. 5.2. T
13、amperA nonabsorptive, nonabrasive, nonbrittle material such as a hard rubber compound having a Shore A durometer hardness of 80 10. The tamper shall have a cross section of about 13 mm by 25 mm (1/2in. by 1 in.) and a length of 125 to 150 mm (5 to 6 in.). The tamping face shall be flat and at right
14、angles to the length of the tamper. 5.3. TrowelSteel bladed, 100 to 150 mm (4 to 6 in.) in length, with straightedges. 5.4. Other EquipmentRubber gloves, scoop, clamps to secure the cover plate, light release oil for oiling the molds, small brush or lint-free cloth for applying and removing excess r
15、elease oil, and burlap or wrapping cloth capable of retaining moisture. 6. SAMPLING 6.1. Samples shall be obtained in accordance with R 60 when the batch equals or exceeds 1 m3(1 yd3). When the batch is less than 1 m3(1 yd3), sample from the batch after discharge. If remixing is required, sample aft
16、er remixing. Begin molding the specimens within an elapsed time of not more than 21/2min from completion of the mixing. Note 2This practice is to be used only for grouts with 100 percent passing the 9.5-mm (3/8-in.) sieve. 6.2. Obtain a representative sample of the mix. Samples shall be a minimum si
17、ze of 2000 g (4 lb) for each set of three cubes to be fabricated. 7. PROCEDURE 7.1. Assemble both portions of the mold and the bottom cover plate. All joints shall be watertight. If not watertight, seal the surfaces where the halves of the mold join by applying a coating of light cup grease (nonwate
18、rsoluble). The amount should be sufficient to extrude slightly when the halves are tightened together. Repeat this process for attaching the mold to the bottom cover plate. Remove any excess grease. Apply a thin coating of release agent to the interior faces of the mold and the bottom cover plate. W
19、ipe the mold faces and base plate as necessary to remove any excess 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-3b R 64-3 AASHTO release agent and to achieve a thin, even coating on the interior s
20、urfaces. Adequate coating is that which is just sufficient to allow a distinct fingerprint to remain following light finger pressure. 7.2. Place a layer of grout about 25 mm (1 in.) (approximately one half of the depth of the mold) in all of the cube compartments. Consolidate according to the consis
21、tency (plastic or fluid) of the mix. 7.2.1. For plastic mixes, tamp the lift in four rounds of 8 tamps for a total of 32 tamps with the rubber tamper in 10 s. See Figure 1 for tamping sequence of each round. Rounds 1 and 3 and Rounds 2 and 4 shall be the same. Figure 1Tamping Sequence 7.2.2. For flu
22、id mixes, puddle the lift five times with a gloved finger. See Figure 2 for puddling sequence. Figure 2Puddling Sequence 7.3. Place the second lift in each of the cube compartments, slightly overfilling each compartment. Consolidate the material in the same fashion as the first lift with the additio
23、nal requirement that, during consolidation of the second lift, any grout forced out onto the top of the mold after each round will be pushed back onto the compartment by means of the tamper or gloved fingers, or both, before the next consolidation round. When consolidation of the grout is completed,
24、 material should extend slightly above the top of the mold. After the last round, push any grout forced onto the top of the mold back into the compartment with the trowel. 7.4. Smooth off the cubes by drawing the flat side of the trowel (with the leading edge slightly raised) once across the top of
25、each cube at right angles to the length of the mold. Then, for the purpose of leveling the mortar and making the mortar that protrudes above the top of the mold of more uniform thickness, draw the flat trailing edge of the trowel (with leading edge slightly raised) once Rounds 1 and 312345678Rounds
26、2 and 41234567812345 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-3b R 64-4 AASHTO lightly along the length of the mold. Cut off the mortar to a plane surface flush with the top of the mold by draw
27、ing the straightedge of the trowel (held nearly perpendicular to the mold) with a sawing motion over the length of the mold. The material shall be flush with the top of the mold. 7.5. Immediately secure the top cover plate to the cube mold. 7.6. Initial CuringImmediately after molding and finishing,
28、 the specimens shall be stored in a secure location away from vibration, for a period of 24 to 28 hours, in a temperature range from 16 to 27C (60 to 80F) in an environment preventing moisture loss from the specimens unless stipulated otherwise by the specifier of tests. Various procedures are capab
29、le of being used during the initial curing period to maintain the specified moisture and temperature conditions. An appropriate procedure or combination of procedures shall be used (Notes 3 and 4). Shield all specimens from direct sunlight and, if used, radiant heating devices. Record the temperatur
30、e using a maximum-minimum thermometer. Note 3A satisfactory moisture environment can be created during the initial curing of the specimens by the following procedures: (1) cover the specimens with removable lids, plastic sheets, or nonabsorbent plates and (2) maintain proper moisture with an air-tig
31、ht sealed container, damp sand pit, or sealed plastic bags. Note 4A satisfactory temperature environment can be controlled during the initial curing of the specimens by one or more of the following procedures: (1) use of ventilation, (2) use of ice, (3) use of thermostatically controlled heating or
32、cooling devices, or (4) use of heating methods such as stoves or light bulbs. 7.7. At the end of the initial curing period as required by the agency, either: 7.7.1. Place the sealed molds into a watertight container. Transport the cube samples immediately to the location of final curing. During tran
33、sport, the cube samples shall be protected from jarring, freezing, and moisture loss; or 7.7.2. Disassemble the mold and carefully remove the cube samples. Using a permanent marker, identify the cube samples. Handling the cube samples very carefully, wrap them in wet burlap or wet towels and place t
34、hem into a watertight container. Transport the cube samples immediately to the location of final curing. During transport, the cube samples shall be protected from jarring, freezing, and moisture loss. 7.8. Final curing shall consist of removing the samples from the transport container and immersing
35、 the cube samples in a lime-saturated water storage tank maintained at a temperature of 23.0 2.0C (73.5 3.5F). They are to remain in the storage tank until time of test. (Curing cube samples of material other than hydraulic cement shall be in conformance with the manufacturers recommendations.) The storage tank shall be made of noncorroding materials. 1Formerly AASHTO Provisional Standard TP 83. First published as a new standard in 2014. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.
