1、Standard Method of Test for Apparent Viscosity of Hot-Poured Asphalt Crack Sealant Using Rotational Viscometer AASHTO Designation: T 366-181Technical Section: 4e, Joints, Bearings, and Geosynthetics Release: Group 2 (June) American Association of State Highway and Transportation Officials 444 North
2、Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-4e T 366-1 AASHTO Standard Method of Test for Apparent Viscosity of Hot-Poured Asphalt Crack Sealant Using Rotational Viscometer AASHTO Designation: T 366-181Technical Section: 4e, Joints, Bearings, and Geosynthetics Release: Group 2 (June) 1.
3、 SCOPE 1.1. This test method outlines the procedure for measuring the apparent viscosity of hot-poured asphalt crack sealant at elevated temperature from 150 to 200C using a rotational viscometer as specified by MP 25 and PP 85. 1.2. The rotational viscometer is a rotating spindle-type viscometer th
4、at meets the requirements of T 316. This test method can be used for general specification and is especially convenient for use in a field laboratory or a plant site. 1.3. Viscosity data obtained with this test method are used to ensure that the hot-poured asphalt crack sealants apparent viscosity i
5、s low enough to fill cracks and, at the same time, high enough not to flow out of the crack. Ideally, the shear rates during the test should match the shear rates the hot-poured asphalt crack sealant experiences during installation. The rotational speed of the spindle was selected at 60 rpm to resem
6、ble field pouring conditions. Changing spindle sizes and rotational speeds affect both the shear rate and the measured apparent viscosity. 1.4. This standard may involve hazardous material, operations, and equipment. This standard does not purport to address all of the safety problems associated wit
7、h its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the application of regulatory limitations prior to use. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standard: MP 25, Performance-Graded Hot-Poured Asphalt Crack Sealant PP 85,
8、Grading or Verifying the Sealant Grade (SG) of a Hot-Poured Asphalt Crack Sealant T 316, Viscosity Determination of Asphalt Binder Using Rotational Viscometer 2.2. ASTM Standards: D5167, Standard Practice for Melting of Hot-Applied Joint and Crack Sealant and Filler for Evaluation E1, Standard Speci
9、fication for ASTM Liquid-in-Glass Thermometers E220, Standard Test Method for Calibration of Thermocouples by Comparison Techniques 2018 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e T 366-2 AASHTO 3
10、. TERMINOLOGY 3.1. apparent viscositythe ratio of shear stress to shear rate for a liquid. This parameter is a measure of the resistance to flow of the liquid. The SI unit of viscosity is the Pascal second (Pas). 3.2. hot-poured asphalt crack sealanthot-poured modified asphaltic materials used in pa
11、vement cracks and joints. Note 1Based on the references, hot-poured asphalt crack sealant is typically applied at a temperature of 160C or above. 4. SUMMARY OF METHOD 4.1. Hot-poured asphalt crack sealant material is homogenized according to ASTM D5167, cut into cubes no larger than 5 mm by 5 mm and
12、 placed into standard containers. Apparent viscosity is measured utilizing the rotational viscometer using a spindle recommended by the hot-pour asphalt crack sealant manufacturer. The spindle shall be attached to the rigid hook attachment and rotates at the speed of 60 rpm. The test shall be conduc
13、ted at the hot-poured asphalt crack sealant manufacturers recommended installation temperature. 5. SIGNIFICANCE AND USE 5.1. This test is intended for hot-poured asphalt crack sealant applied to roadway joints and cracks. 5.2. This procedure is designed to simulate the viscosity of hot-poured asphal
14、t crack sealant while pouring the sealant into a crack. 5.3. Hot-poured asphalt crack sealant must be homogenized (ASTM D5167) before measuring the apparent viscosity by this method. 6. APPARATUS 6.1. Rotational Viscometer. 6.2. Temperature Controlling UnitMaintaining a temperature ranging from 170
15、to 193C within a tolerance of 1C. 6.3. Laboratory OvenAny laboratory standard oven capable of producing and maintaining a temperature ranging from 170 to 193C within a tolerance of 1C. 6.4. Rigid hook attachment especially designed as an attachment in the rotational viscometer to measure hot-poured
16、asphalt crack sealant viscosity. 6.5. Aluminum containers or stainless steel containers. 6.6. The rotational viscometer contains sensors that monitor the applied torque and automatically display the calculated apparent viscosity. The keypad on the instrument is used to enter the spindle number, zero
17、 the signal, and run the test at a selected speed. Torque and viscosity can be recorded manually, or an interface can be used to send the signal from the instrument to a personal computer. Optional software is also available that can be used to program preselected thermal profiles. This software is
18、not needed for the specification test. However, the unit must be used to control the temperature and thereby obtain acceptable reproducibility. 2018 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e T 36
19、6-3 AASHTO 7. HAZARDS 7.1. Standard laboratory caution should be used in handling hot-poured asphalt crack sealant in accordance with ASTM D5167, and when using the temperature controlling unit. Required safety procedures should be followed when chemical agents are used. 8. PREPARATION OF APPARATUS
20、8.1. The rotational viscometer and temperature controlling unit must be leveled to function properly. A bubble-type level is normally located on top of the viscometer and temperature controlling unit and is adjusted by using leveling screws located on the base. Preparing the device, leveling and ali
21、gning the viscometer on the stand, and setting the temperature of the temperature controlling unit are explained in the operation instructions provided by the manufacturer. The detailed steps for testing are specified in T 316. 9. CALIBRATION AND STANDARDIZATION 9.1. Temperatures of the ovens should
22、 be calibrated in accordance with each users quality assurance program. 9.2. Thermometer (temperature detector)Verify the calibration of the temperature-sensing device to 0.1C every 6 months by placing any type of asphalt binder or hot-poured crack sealant sample in the testing chamber in accordance
23、 with ASTM E1 or ASTM E220, as applicable. 9.3. The accuracy of the viscometer should be checked annually using a certified reference fluid of known viscosity following the procedure recommended by the manufacturer. The viscosity measured shall be within 2 percent or the rotary transducer requires r
24、ecalibration. 10. PREPARATION OF SAMPLES AND TEST SPECIMENS 10.1. All apparent viscosity measurements must be performed on homogenized hot-poured asphalt crack sealant. Sealant homogenization is conducted in accordance with the procedure presented in ASTM D5167. 10.2. Once homogenized, hot-poured as
25、phalt crack sealant should be cooled down to room temperature and stored for 2 h before usage. It is recommended that a can or plastic-lined box be used as a container during the cooldown period. The container must be of sufficient size so that the hot-poured asphalt crack sealant depth is no greate
26、r than 100 mm to allow for rapid cooling. 10.3. Cut 10.5 0.5 g of the homogenized hot-poured asphalt crack sealant into small cubes no larger than 5 mm by 5 mm, and place the cubes in stainless steel or aluminum containers. (See Figure 1.) 2018 by the American Association of State Highway and Transp
27、ortation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e T 366-4 AASHTO Figure 1Hot-poured Asphalt Crack Sealant Sample Cut into Small Pieces 11. PROCEDURE 11.1. Preheat the temperature controlling unit to test temperature and, unless otherwise noted, use the insta
28、llation temperature recommended by the hot-poured asphalt crack sealant manufacturer. Preheat the spindle in a laboratory oven to the installation temperature of the hot-poured asphalt crack sealant recommended by the hot-poured asphalt crack sealant manufacturer. 11.2. Place the aluminum or stainle
29、ss steel container containing sealant in the temperature controlling unit. 11.3. Turn on the viscometer and zero it. 11.4. Allow 5 min for sealant to melt at the test temperature before inserting the spindle into the sample to equilibrate. 11.5. Assemble spindle and attach the spindle to a rigid rod
30、 by using the set screw on the rod (see Note 2). Note 2The current hook that is used for asphalt binder should not be applied to hot-poured asphalt crack sealant that contains rubber fillers, which would affect the spindles rotation. Figures 2 through 4 illustrate the spindle and the rigid rod. 2018
31、 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e T 366-5 AASHTO (a) (b) Figure 2Rigid Rod with (a) Spindle Assembled and (b) Schematic of Rigid Rod 2018 by the American Association of State Highway and
32、 Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e T 366-6 AASHTO Figure 3Lower Opening of 2.5 mm to Screw the Spindle to the Rigid Rod Figure 4Upper Opening of 2.5 mm to Screw the Rod to the Viscometer Head 11.6. Allow 20 min to stabilize the temperat
33、ure. Meanwhile, adjust stirring speed of the spindle to 60 rpm. Note 3Excessive heating may cause volatiles to be lost from the sample or polymer chains to be degraded, both of which lead to a reduction in measured apparent viscosity. In general, during testing, the sample should not be heated to te
34、mperatures greater than the pouring temperature recommended by the manufacturer. 11.7. Start testing and record the data right after 30 s of stirring. After the data are recorded, stop the test, clean the spindle, and remove the aluminum or stainless steel container. Note 4Data should be collected a
35、fter a specific rotation time. Excessive mixing may cause segregation, especially in the case of a rubber-modified hot-poured asphalt crack sealant. 11.8. Insert the next specimen and repeat steps in Sections 11.2 to 11.7 until four replicates are tested for each hot-poured asphalt crack sealant. 20
36、18 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e T 366-7 AASHTO 12. CALCULATION OF RESULTS 12.1. The viscosity is reported as the average of the best three out of four readings. The rotational viscom
37、eter measures the apparent viscosity in centipoise. The measured viscosity may be converted to Pascal seconds by using the conversion factor 1 cps = 0.001 Pas. 13. REPORT 13.1. Report the following information: 13.1.1. Sealant identification and supplier, 13.1.2. Lot number, 13.1.3. Date received, 1
38、3.1.4. Date of apparent viscosity measurement, 13.1.5. Recommended pouring temperature, 13.1.6. Safe heating temperature, 13.1.7. Any deviations from test temperature, 13.1.8. Torque in percent, and 13.1.9. Average viscosity in Pas 14. PRECISION AND BIAS 14.1. Single-Operator Precision (Repeatabilit
39、y)The figures in Column 2 of Table 1 are the coefficient of variation that have been found to be appropriate for the conditions of the test described in Column 1. Two results obtained in the same laboratory, by the same operator using the same equipment, in the shortest practical period of time, sho
40、uld not be considered suspect unless the difference in the two results, expressed as a percent of their mean, exceeds the value given in Table 1, Column 3 (Acceptable Range of Three Test Results). 14.2. Multilaboratory Precision (Reproducibility)The figures in Column 2 of Table 1 are the coefficient
41、 of variation that have been found to be appropriate for the conditions of the test described in Column 1 (Condition). Two results submitted by two different operators testing the same material in different laboratories shall not be considered suspect unless the difference in the two results, expres
42、sed as percent of their mean, exceeds the values given in Column 3 (Acceptable Range of Three Test Results). 2018 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e T 366-8 AASHTO Table 1Precision Estimat
43、es Coefficient of Variation, Acceptable Range of Three Test Results, Condition (1s%)a(d2s%)aSingle-operator precision: Average viscosity (Pas) 1.62 5.4bMultilaboratory precision: Average viscosity (Pas) 5.90 16.9 aThe precision estimates given in Table 1 are based on the analysis of test results fro
44、m seven sealants with a wide range of rheological properties. The data analyzed include results from seven laboratories that conducted each test in four replicates. bAs an example, two tests conducted on the same material yield viscosity results of 3.12, 3.05, 3.15 Pas, respectively. The average of
45、these three measurements is 3.11 Pas. The acceptable range of results is then 5.4 percent of 3.11 or 0.17 Pas. As the greatest difference between each two, 0.1, is less than 0.17, the results are within the acceptable range. 15. KEYWORDS 15.1. Apparent viscosity rotational viscometer; crack; fillers
46、; hot-poured asphalt crack sealant; joint. 16. REFERENCES 16.1. Al-Qadi, I. L., J. F. Masson, E. Fini, S. H. Yang, and K. K. McGhee. Development of Performance-Based Guidelines for Selection of Bituminous-Based Hot-Poured Pavement Crack Sealant: An Executive Summary Report. VTRC 09-CR7. Virginia Tra
47、nsportation Research Council, Charlottesville, VA, 2009. Available at http:/vtrc.virginiadot.org/PubDetails.aspx?PubNo=09-CR7 16.2. Al-Qadi, I. L., E. H. Fini, K. K. McGhee, and M. A. Elseifi. Development of Apparent Viscosity Test for Hot-Poured Crack Sealants, Final Report. No. ICT-08-027, Illinoi
48、s Center for Transportation, Rantoul, IL, December 2008(b). Available at https:/www.ideals.illinois.edu/bitstream/handle/2142/45987/ICT-08-027.pdf?sequence=2 1Formerly AASHTO Provisional Standard TP 85. First published as a full standard in 2017. 2018 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.
