1、Standard Method of Test for Measuring Interfacial Fracture Energy of Hot-Poured Crack Sealant Using a Blister Test AASHTO Designation: TP 90-161 Release: Group 2 (June 2016) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 2
2、0001 TS-4e TP 90-1 AASHTO Standard Method of Test for Measuring Interfacial Fracture Energy of Hot-Poured Crack Sealant Using a Blister Test AASHTO Designation: TP 90-161Release: Group 2 (June 2016) 1. SCOPE 1.1. The blister test is used to determine the interfacial fracture energy (IFE) of hot-pour
3、ed crack sealant at the application temperatures. 1.2. The blister test is a fracture test. The objective of the test is to apply tensile forces using hydrostatic pressure to delaminate sealant from a substrate. A thin film of sealant is poured on the top of a substrate (usually aluminum) disk that
4、has a hole at the center. Hydrostatic pressure is applied through this hole at a constant flow rate causing delamination between the sealant film and substrate. Sealant deformation and applied hydrostatic pressure are recorded as a function of time. The amount of energy required to achieve complete
5、delamination is called interfacial fracture energy and can be calculated from the pressure-deformation curve. This energy is considered a measure of bonding potential. 1.3. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
6、 of the user of this standard to establish and follow appropriate health and safety practices and to determine the applicability of regulatory limitations prior to use. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standard: R 18, Establishing and Implementing a Quality Management System for Construction Mate
7、rials Testing Laboratories 2.2. ASTM Standards: D5167, Standard Practice for Melting of Hot-Applied Joint and Crack Sealant and Filler for Evaluation E1, Standard Specification for ASTM Liquid-in-Glass Thermometers E220, Standard Test Method for Calibration of Thermocouples By Comparison Techniques
8、3. TERMINOLOGY 3.1. Definitions: 3.1.1. hot-poured crack sealantshot-poured modified asphaltic materials used to seal pavement cracks and joints. 3.1.2. interfacial fracture energy (IFE)the energy required to separate bituminous sealant from a substrate. 2016 by the American Association of State Hig
9、hway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e TP 90-2 AASHTO 4. SUMMARY OF METHOD 4.1. Crack sealant material is homogenized following the procedure given in ASTM D5167. For each test, including four replicates, cut 320 g of sealant and he
10、at to the manufacturers recommended pouring temperature. Sealant will be poured in the mold assembled on top of an annular-shaped disk of substrate. An aluminum plug will be inserted into the hole of the substrate to close it. The sealant will be poured on top of the plugged substrate to provide a f
11、ilm of 4.6-mm thickness. Hydrostatic pressure is applied through the hole to cause delamination between the sealant film and the substrate. Sealant deformations and applied hydrostatic pressure can be recorded as a function of time. The amount of energy required for complete delamination is called i
12、nterfacial fracture energy and can be calculated from the pressure-deformation curve. This energy can be considered an indication of bonding potential. 5. SIGNIFICANCE AND USE 5.1. This procedure is designed to measure the adhesion potential of hot-poured sealant to aggregate. 5.2. Sealants must be
13、rehomogenized (ASTM D5167) before measuring adhesion by this method. 6. APPARATUS 6.1. Modified direct tension test (DTT) machine or an equivalent system with environmental chamber and motor or screw driven actuator; 6.2. Chiller that can reach 40 0.5C; 6.3. Laboratory OvenAny standard laboratory ov
14、en capable of producing and maintaining temperatures up to 200C 2.0C; 6.4. Release agent; and 6.5. Four test setups, four molds, four plugs, and four rubber bands. (See Figures 1, 2, and 3.) 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplicat
15、ion is a violation of applicable law.TS-4e TP 90-3 AASHTO Figure 1Schematic of the Substrate Disk Figure 2Schematic of the Plug 25.40 mm127.00 mm6.35mm63.50 mm25 mm10 mm5 mm 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violatio
16、n of applicable law.TS-4e TP 90-4 AASHTO Figure 3Schematic of One Section of the Four-Piece Mold 7. HAZARDS 7.1. Standard laboratory caution should be used in handling hot sealant in accordance with ASTM D5167 and when using the Direct Tension/Blister Tester (DTT/Blister). Required safety procedures
17、 should be followed when chemical agents are used. 8. PREPARATION OF APPARATUS 8.1. The test setup used to hold the blister molds must be placed in the environmental bath or chamber and leveled to function properly. The environmental chiller must be adjusted to specific temperature. 9. CALIBRATION A
18、ND STANDARDIZATION 9.1. Temperature of the ovens should be calibrated according to a quality management system meeting the requirements of R 18. 9.2. Temperature of the chiller should be calibrated according to a quality management system meeting the requirements of R 18. 10.15 mm5.9 mm4.8 mm3.3mm5.
19、4 mmA-AA AR: 66.80 mmR: 60.95 mmR: 63.50 mm 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e TP 90-5 AASHTO 9.3. Thermometer (temperature detector)Verify the calibration of the temperature-sensing
20、device to 0.1C every 6 months in accordance with ASTM E1 or ASTM E220, as applicable. 10. PREPARATION OF SAMPLES AND TEST SPECIMENS 10.1. All adhesion potential measurements must be performed on rehomogenized sealant. Follow the procedure for homogenization given in ASTM D5167. It is recommended tha
21、t a minimum of 400 g of sealant be homogenized. 10.2. Once homogenized, hot sealant should be molded, cooled, and stored for later usage. To store the sealant, it is recommended that a can or plastic-lined box be used. The mold must be of sufficient size that the sealant depth is no greater than 100
22、 mm to allow for rapid cooling. 10.3. Adjust the ovens temperature to the recommended pouring temperature for the sealant being tested. 10.4. Turn on the DTT/Blister machine, load the program, and cool the chiller to test temperature. 10.5. Use a compass to draw a circle 27 mm in diameter on adhesiv
23、e-backed fluoropolymer (FEP) film. 10.6. Punch out the circle using a sharp manual punch. 10.7. Peel the FEP film and place it on a level surface, adhesive side up (Figure 4). 10.8. Place the needle on the center (marked with the compass) of the FEP film (Figure 4). 10.9. Place the flat side of the
24、plug on top of the needle and let the needle go through the plug (Figure 4). Figure 4Performing Steps 10.7 through 10.9 10.10. Press the plug on the film gently to make sure it has adhered to the film. 10.11. Spray release agent (Figure 5) on the plug while keeping it inclined. 2016 by the American
25、Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e TP 90-6 AASHTO Figure 5Spraying Release Ag ent on the Plugs 10.12. Taking care not to contaminate the surface of the disk, place the plug on top of the annular disk (Fig
26、ure 6). Figure 6Placing the Plug on the Annular Disk and Pulling It from Underneath until the Disk Fits in the Hole and the Film Edges Sit on the Disk 10.13. Place the substrate disk and the plug on a setting board. 10.14. Spray release agent on the molds (Figure 7). Figure 7Spraying Release Ag ent
27、on the Molds 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e TP 90-7 AASHTO 10.15. Assemble the mold on top of the disk (Figure 8). Figure 8Assembling the Molds on Top of the Disk 10.16. Wrap the
28、mold with a rubber band stretched through the groove around the mold to keep the components in place (Figure 9). Figure 9Using a Rubber Band to Keep the Mold Together 10.17. Prepare four cans of sealant by cutting 80 g of homogenized sealant for each. 10.18. Place the can in the oven for 15 min (Fig
29、ure 10), remove it from the oven, stir the sealant thoroughly, and place it back in the oven for another 15 min. 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e TP 90-8 AASHTO Figure 10Heating 80
30、g of Homogenized S ealant at Recommended Pouring Temperature for 30 min 10.19. Remove the can from the oven, stir the sealant thoroughly, and pour into all the assembled setups. Use four replicates for each sealant. Care should be taken in filling up the molds to prevent any trapped air bubbles in t
31、he samples (Figure 11). Figure 11Pouring Sealant onto the Center Top of the Plug so that the Sealant Flows to Fill the Mold 10.20. Let samples set 1 h at room temperature (Figure 12). 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is
32、a violation of applicable law.TS-4e TP 90-9 AASHTO Figure 12Sealant Setting for 1 h at Room Temperature 10.21. Trim the excessive sealant away with a heated putty knife (Figure 13). Move the putty knife once over and parallel to the interface of the sample; trimming direction shall not be changed du
33、ring trimming. Use a well-heated putty knife to prevent any shearing of the sealant. Figure 13Trimming Excess Sealant with a Heated Putty Knife 10.22. Place the specimens on the cooling rack (Figure 14). Care should be taken not to disturb the specimens. 2016 by the American Association of State Hig
34、hway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e TP 90-10 AASHTO Figure 14Placing the Disks on the Rack with Clearance between Each Specimen 10.23. Place the rack in the cooling bath for 15 min (Figure 15). Figure 15Placing the Rack in the Ba
35、th for 15 min 10.24. Remove the rubber band and gently disassemble the mold of one specimen (Figure 16). 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e TP 90-11 AASHTO Figure 16Disassembling the
36、Mold 10.25. Remove the plug and place the specimen back in the bath (Figure 17). Figure 17Removing the Plug from Each Specimen 10.26. Repeat steps 10.24 and 10.25 until all specimens are demolded. 10.27. Leave the specimens in the cooling bath for 45 min before running the test. 10.28. Open the Blis
37、ter test builder program; then open the outlet valve to prevent pressure from being applied to the specimen before the test starts. Place the specimen on the setup and clamp the specimen tightly. Check the program settings and run the test. Record the data. 10.29. Examine the failure surfaces visual
38、ly for each replicate to ensure adhesive failure occurred. If sealant cohesive breakage occurred, discard the data. (See Figure 18.) Note 1Sealant cohesive breakage is defined as rupt ure in the blister prior to the start of delamination or during delamination of sealant from the disk. Sealant piece
39、s covering an area of approximately less than 10% of total disk area and remaining at the periphery of the disk after test completion is not considered as sealant cohesive breakage (See Figure 18.) A sudden drop of load is an indication of sealant cohesive breakage. Adhesive failure usually follows
40、a gradual delamination of sealant from the disk and is reflected by a smooth load reduction as blister size increases. 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law.TS-4e TP 90-12 AASHTO Figure 18Remo
41、ving the Specimen and Verifying that the Type of Failure Was Adhesive Failure, in Which Sealant Separates from the Disk 11. CALCULATION OF RESULTS 11.1. Find the maximum load (Pmax) to failure and its correspondent displacement (d). 11.2. Find the Interfacial Fracture Energy, IFE, by multiplying hal
42、f of the maximum load and the corresponding displacement. maxIFE P d= (1) where: IFE = Interfacial Fracture Energy, J/m2 = the force factor and is equal to 0.5 Pmax= the maximum load to failure, N; and d = the displacement at the maximum load, m. 12. REPORT 12.1. Report the following information: 12
43、.1.1. Sealant identification and supplier, 12.1.2. Lot number, 12.1.3. Date received, 12.1.4. Date of apparent viscosity measurement, 12.1.5. Recommended pouring temperature, 12.1.6. Safe heating temperature, 12.1.7. IFE, J/m2, and 12.1.8. Any deviations from test temperature. 13. PRECISION AND BIAS
44、 13.1. Single-Operator Precision (Repeatability)The results obtained in the same laboratory by the same operator using the same equipment, in the shortest practical period of time, should not be 2016 by the American Association of State Highway and Transportation Officials. All rights reserved. Dupl
45、ication is a violation of applicable law.TS-4e TP 90-13 AASHTO considered suspect unless the difference in the two results, expressed as a percent of their mean, exceeds the value given in Table 1. Table 1Precision Estimates Condition Coefficient of Variation (1s%)aSingle-operator precision: Average
46、 IFE (J/m2) 8.77 aThe precision estimate given in Table 1 is based on the analysis of test results from 12 sealants with a wide range of rheological properties. The data analyzed include results from two operators in the same laboratory who conducted each test in four replicates. 14. KEYWORDS 14.1.
47、Adhesion; blister; bond; crack; fillers; hot-poured bituminous sealant; interfacial fracture energy; joint. 15. REFERENCES 15.1. 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 Crac
48、k Sealant: An Executive Summary Report. VTRC 09-CR7. Virginia Transportation Research Council, Charlottesville, VA, 2009. Reference for AASHTO TP 85 through TP 90 http:/vtrc.virginiadot.org/PubDetails.aspx?PubNo=09-CR7 15.2. Al-Qadi, I. L. and E. Fini. Development of the Crack Sealant Adhesion Test
49、(CSADT) Specification, Journal of Testing and Evaluation, Vol. 39, No. 2, ASTM, 2011, pp. 1-7, Reference for AASHTO TP 89 and TP 90 15.3. Al-Qadi, I. L., E. H. Fini, H. D. Figueroa, J. F. Masson, and K. K. McGhee. Adhesion Testing Procedure for Hot-Poured Crack Sealants, Final Report. No. ICT-08-026. Illinois Center for Transportation, Rantoul, IL, December 2008. Reference for AASHTO TP 89 and TP 90 https:/www.ideals.illinois.edu/bitstream/handle/2142/45986/ICT-08-026.pdf?sequence=2 1This provisional standard was
