1、Standard Method of Test for Evaluation of Asphalt Release Agents AASHTO Designation: TP 102-12 1. SCOPE 1.1. This method covers the laboratory performance evaluation of asphalt release agents. These release agents are used for coating tools and truck beds to prevent asphalt binder or hot mix asphalt
2、 (HMA) from adhering. The release agents should perform this function without causing degradation (stripping) of the hot mix asphalt. 1.2. This standard may involve hazardous materials, operations, and equipment. It does not purport to address all safety concerns associated with its use. It is the r
3、esponsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 320, Performance-Graded Asphalt Binder M 323, Superpave Volumetric Mix Design T 85,
4、 Specific Gravity and Absorption of Coarse Aggregate T 312, Preparing and Determining the Density of Hot Mix Asphalt (HMA) Specimens by Means of the Superpave Gyratory Compactor 2.2. ASTM Standards: D 93, Standard Test Methods for Flash Point by Pensky-Martens Closed Cup Tester D 1475, Standard Test
5、 Method for Density of Liquid Coatings, Inks, and Related Products D 2369, Standard Test Method for Volatile Content of Coatings E 1252, Standard Practice for General Techniques for Obtaining Infrared Spectra for Qualitative Analysis 2.3. Other Standard: TxDOT Test Procedure Tex-530-C, Effect of Wat
6、er on Bituminous Paving Mixtures 3. SUMMARY OF TEST METHOD 3.1. The test method uses three key performance measures: 3.1.1. In the 7-Day Asphalt Stripping Test, a specimen of hot mix asphalt binder is soaked in the release agent for seven days, alongside a control specimen of release agent with no h
7、ot mix asphalt . The specimens are evaluated at the end of the soak period to determine the degree of stripping that occurred. TS-2b TP 102-1 AASHTO 2012 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.3.1.2.
8、 In the Mixture Slide Test, a specimen of hot mix asphalt is applied to a steel plate that has been treated with the release agent. The plate is tilted to allow the hot mix asphalt to slide free. This process is repeated two more times. The degree of adhesion to the plate is determined by gain in we
9、ight. 3.1.3. In the Asphalt Performance Test, hot asphalt binder is poured onto the treated plate, allowed to cool, and then peeled away. The degree of adhesion to the plate is determined by gain in weight. This process is repeated until 10 percent of the binder has adhered to the plate. The amount
10、of retained binder is recorded for each application cycle. 3.2. The specific gravity, percent solids, and infrared spectrum of the release agent are measured and recorded. 4. SIGNIFICANCE AND USE 4.1. The 7-Day Asphalt Stripping Test measures the tendency for the release agent to remove asphalt bind
11、er from the hot mix asphalt. The agent is evaluated in both its concentrated form and at the diluted concentration recommended for use by the manufacturer. 4.2. The Mixture Slide Test simulates a truck bed to determine the tendency of the asphalt to adhere to the bed when the release agent is used.
12、4.3. The Asphalt Performance Test measures the tendency for asphalt binder to adhere to truck beds or tools. 4.4. The hot mix asphalt used for testing is made under Superpave mix design standards to provide a mixture with repeatable behavior that will not tend to exhibit stripping when exposed to wa
13、ter. 4.5. The specific gravity, percent solids, and infrared spectrum are intended to be used as reference parameters to verify product formulations of future samples. 4.6. This method is intended to determine the properties of these materials. Acceptability of a material, based upon the data genera
14、ted as a result of the testing and evaluation in this practice, is the responsibility of the user. 4.7. Standard laboratory conditions are defined as a temperature of 24 4C (77 7F) and a relative humidity of 50 10 percent. 5. SEVEN-DAY ASPHALT STRIPPING TEST 5.1. Apparatus: 5.1.1. Jarseight (8) 0.5-
15、L (1-pt) glass canning jars or equivalent with a lid for sealing; 5.1.2. Ovencapable of attaining a minimum temperature of 150C (302F); and 5.1.3. Balancereadable to 0.1 g and accurate to 0.5 g. TS-2b TP 102-2 AASHTO 2012 by the American Association of State Highway and Transportation Officials.All
16、rights reserved. Duplication is a violation of applicable law.5.2. Materials: 5.2.1. Either a plant- or a laboratory-mixed sample of hot mix asphalt (HMA) meeting the following requirements: 5.2.1.1. Meets M 323, Table 3 requirements for 12.5-mm (0.5-in.) nominal aggregate size. 5.2.1.2. Contains an
17、 asphalt binder meeting the requirements of PG 76-22 as defined in M 320, Table 1. 5.2.1.3. The percent absorption of the coarse aggregates in the HMA is less than 0.5 percent when tested according to T 85. 5.2.1.4. Is prepared according to the procedure outlined in T 312, Section 8 for HMA Mixture
18、Preparation. 5.2.1.5. Tested and passed TxDOT Test Procedure Tex-530-C, “Effect of Water on Bituminous Paving Mixtures,” with zero (0) percent stripping. Provide the documentation to support the test results. 5.2.2. Distilled and deionized (DDI) water. 5.3. Procedure: 5.3.1. Obtain a representative
19、sample of hot mix asphalt (HMA). Heat the mixture to 143C (290F). 5.3.2. Split 300 g (0.66 lb) of mix into six equal amounts of 50 g (0.11 lb) each and place into six 0.5-L (1-pt) glass jars. 5.3.3. Place a minimum of 100 mL (3 fl oz) of the asphalt release agent at full strength into each of three
20、glass jars containing the hot mix asphalt (HMA) described in Section 5.3.2, making sure the mixture is completely covered by the asphalt release agent. 5.3.4. Pour the asphalt release agent at full strength into an empty jar to the same level as those in Section 5.3.3 and use as the control sample.
21、5.3.5. Prepare approximately 500 mL (15 fl oz) of asphalt release agent diluted with DDI water to the concentration recommended by the manufacturer. 5.3.6. Place a minimum of 100 mL (3 fl oz) of the asphalt release agent at the diluted strength into the remaining 3 glass jars containing the hot mix
22、asphalt (HMA) described in Section 5.3.2, making sure the mixture is completely covered by the asphalt release agent. 5.3.7. Pour the asphalt release agent at the diluted strength into an empty jar to the same level as those in Section 5.3.6 and use as the control sample. 5.3.8. Cover the 8 samples
23、and leave them undisturbed for 168 2 h. 5.3.9. At the end of the specified time, compare the color of each replicate of asphalt release agent samples containing the mix to the control samples. Separate the mixture from the asphalt release agent and examine for any stripping of the asphalt from the a
24、ggregate. TS-2b TP 102-3 AASHTO 2012 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.5.3.10. Rate the asphalt release agent and the diluted asphalt release agent according to the following rating system: No S
25、trippingNo stripping or discoloration occurred Slight StrippingDiscoloration of the asphalt release agent Moderate StrippingDiscoloration and stripping of the fine aggregate Severe StrippingDiscoloration, stripping of the coarse and fine aggregate 5.4. Record the amount of visual stripping that is n
26、oted for both the full-strength and diluted asphalt release agents, and the dilution ratio(s) used. 6. MIXTURE SLIDE TEST 6.1. Apparatus: 6.1.1. Ovencapable of attaining a minimum temperature of 150C (302F); 6.1.2. Unit Weight BucketA 2831.7-cm3(0.1-ft3) unit weight bucket filled with sand to a weig
27、ht of 9.1 kg (20 lb); 6.1.3. Plateone 16-gauge steel or aluminum plate, 305 by 305 mm (12 by 12 in.) to 457 by 457 mm (18 by 18 in.), with a textured surface that simulates the inside of an average truck bed used for hauling hot mix asphalt (HMA); 6.1.4. Balancereadable to 0.1 g and accurate to 0.5
28、g; 6.1.5. Waxed paperstandard waxed paper; 6.1.6. Spray bottle used to apply the release agent; and 6.1.7. A 1-L (1-qt) metal container, a large sample pan, a scoop, and a spatula. 6.2. Materials: 6.2.1. Either a plant- or a laboratory-mixed sample of hot mix asphalt (HMA) meeting the following requ
29、irements: 6.2.1.1. Meets M 323, Table 3 requirements for 12.5-mm (0.5-in.) nominal aggregate size. 6.2.1.2. Contains an asphalt binder meeting the requirements of PG 76-22 as defined in M 320, Table 1. 6.2.1.3. The percent absorption of the coarse aggregates in the HMA is less than 0.5 percent when
30、tested according to T 85. 6.2.1.4. Is prepared according to the procedure outlined in T 312, Section 8 for HMA Mixture Preparation. 6.3. Procedure: 6.3.1. Obtain a representative sample of hot mix asphalt (HMA). Heat a minimum of 1600 g (3.53 lb) of mixture to 143C (290F) for 45 to 60 min. TS-2b TP
31、102-4 AASHTO 2012 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.6.3.2. Place a 2831.7-cm3(0.1-ft3) unit weight bucket filled with sand to a weight of 9.1 kg (20 lb) in an oven and heat to 143C (290F) for 45
32、 to 60 min. 6.3.3. Spray the metal plate placed in the horizontal direction with the asphalt release agent at the recommended dilution rate so that the surface is evenly coated. 6.3.4. Allow the metal plate to stand undisturbed for 5 min. 6.3.5. Weigh the metal plate to the nearest 0.1 g and record.
33、 6.3.6. Place 500 10 g of the mixture on the metal plate. 6.3.7. Place a sheet of waxed paper on top of the mixture. 6.3.8. Place the sand-filled bucket on top of the waxed paper and mixture. 6.3.9. Allow the mixture and the sand-filled bucket to stand for 1 h 5 min. 6.3.10. Remove the bucket from t
34、he top of the mixture. 6.3.11. Tilt the metal plate to approximately a 45-degree angle and tap the plate three times on the table to help loosen the mixture from the plate. 6.3.12. Repeat steps in Sections 6.3.6 through 6.3.11 two additional times, without respraying the metal plate. 6.3.13. Weigh t
35、he metal plate to the nearest 0.1 g and record. 6.3.14. Calculate the amount of binder that remains adhered to the plate to the nearest 0.1 g. Use the following formula: Amount of Binder = Final Weight of Plate Initial Weight of Plate 6.4. Record the amount of binder in grams that remained adhered t
36、o the plate. 7. ASPHALT PERFORMANCE TEST 7.1. Apparatus: 7.1.1. Ovencapable of attaining a temperature of 150C (302F) or more; 7.1.2. Plateone 16-gauge steel or aluminum plate, 305 by 305 mm (12 by 12 in.) to 457 by 457 mm (18 by 18 n.), with a textured surface that simulates the inside of an averag
37、e truck bed used for hauling hot mix asphalt (HMA) s; 7.1.3. Balancereadable to 0.1 g and accurate to 0.5 g; 7.1.4. Spray bottleused to apply the asphalt release agent; and TS-2b TP 102-5 AASHTO 2012 by the American Association of State Highway and Transportation Officials.All rights reserved. Dupli
38、cation is a violation of applicable law.7.1.5. A 1-L (1-qt) metal container and a spatula. 7.2. Materials: 7.2.1. PG 76-22 asphalt binder meeting the requirements of M 320, Table 1. 7.3. Procedure: 7.3.1. Pour the binder into a 1-L (1-qt) container and place the container into a 143C (290F) oven for
39、 45 5 min. 7.3.2. Spray the metal plate with the asphalt release agent at the recommended dilution rate and provide an even coating. 7.3.3. Allow the metal plate to stand undisturbed for 5 min. 7.3.4. Weigh the metal plate to the nearest 0.1 g and record. 7.3.5. Remove the asphalt binder from the ov
40、en and stir for 30 5 s. 7.3.6. With the metal plate on the tared scale, pour 20 2 g of asphalt binder on the metal plate. Return the 1-L (1-qt) container to the oven. Determine and record the weight of the poured binder to the nearest 0.1 g. 7.3.7. Allow the binder to cool to touch (normally 5 min).
41、 7.3.8. Using a small spatula, lift up one edge of the binder a sufficient amount to be grasped firmly with fingers, and attempt to remove the binder in one continuous pull. Do not attempt to remove additional binder that remains on the plate. 7.3.9. Weigh the metal plate with the retained asphalt b
42、inder to the nearest 0.1 g and record. Record the weight and the pour number. 7.3.10. Calculate the percent of binder that remains adhered to the plate to the nearest 0.1 percent. Use the following formula: Plate Weight (g) with Retained Binder Initial Plate Weight (g)%Binder = 100Poured Binder Weig
43、ht (g) 7.3.11. Repeat steps in Sections 7.3.5 through 7.3.10 until the percent of retained binder is at least 10.0 percent. 7.4. Record the pour number and the percent binder retained on the plate for each pour. 8. PRODUCT FORMULATION REFERENCE PARAMETERS 8.1. Obtain a reference infrared spectrum fr
44、om a representative sample in accordance with ASTM E 1252, with a resolution of at least 4 cm1and a range of 4000 cm1to 600 cm1. TS-2b TP 102-6 AASHTO 2012 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.8.2.
45、 Determine the percent solids of a representative sample in accordance with ASTM D 2369. 8.3. Measure the specific gravity of a representative sample in accordance with ASTM D 1475. 9. REPORT 9.1. Report the following for each sample: 9.1.1. The degree of stripping observed for each replicate of the
46、 7-Day Asphalt Stripping Test, for both the diluted and undiluted specimens; 9.1.2. The mass of asphalt retained on the plate after three cycles in the Mixture Slide Test; 9.1.3. The percent of asphalt retained on the plate for each cycle of the asphalt performance test; 9.1.4. The specific gravity
47、of the sample; 9.1.5. The percent solids of the sample; and 9.1.6. A graph of the infrared spectrum of the sample with contact information for obtaining the original data. 10. PRECISION AND BIAS 10.1. Precision statements for this method are not available at this time. 11. KEYWORDS 11.1. asphalt release agents. TS-2b TP 102-7 AASHTO 2012 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.
