AASHTO T 329-2015 Standard Method of Test for Moisture Content of Asphalt Mixtures by Oven Method.pdf

1、 Standard Method of Test for Moisture Content of Asphalt Mixtures by Oven Method AASHTO Designation: T 329-15 American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-2c T 329-1 AASHTO Standard Method of Test for Moisture C

2、ontent of Asphalt Mixtures by Oven Method AASHTO Designation: T 329-15 1. SCOPE 1.1. This method is intended for the determination of moisture content of asphalt mixtures by drying in an oven. 1.2. The values stated in SI units are to be regarded as the standard. 1.3. This standard may involve hazar

3、dous materials, operations, and equipment. This standard does not purport to address all of the safety concerns 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 limitation

4、s prior to use. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 231, Weighing Devices Used in the Testing of Materials R 47, Reducing Samples of Hot Mix Asphalt (HMA) to Testing Size T 168, Sampling Bituminous Paving Mixtures 3. SUMMARY OF TEST METHOD 3.1. A test specimen of asphalt mixture is drie

5、d in a forced-air, ventilated, or convection oven to constant mass. 4. APPARATUS 4.1. Balance or Scale2-kg (4.4-lb) capacity, readable to at least 0.1 g and conforming to the requirements of M 231. 4.2. Forced-Air, Ventilated, or Convection Ovencapable of maintaining the temperature surrounding the

6、sample at 163 14C (325 25F). 4.3. Sample ContainerThe container in which the sample is dried shall be of sufficient size to contain the sample without danger of spilling and to allow the sample to be evenly distributed in a manner that will allow completion of the test in an expeditious manner. 4.4.

7、 ThermometersReadable to the nearest 2C (4F), for determining temperatures of asphalt mixtures. Armored-glass, dial type, or digital thermometers with metal stems are recommended. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a vio

8、lation of applicable law.TS-2c T 329-2 AASHTO 5. SAMPLE 5.1. A sample of asphalt mixture shall be obtained in accordance with T 168. 5.2. The sample shall be reduced in size in accordance with R 47. The size of the test sample shall be a minimum of 1000 g. 6. PROCEDURE 6.1. Determine and record the

9、mass of the sample container including any material used to line the sample container to the nearest 0.1 g. Note 1When using paper or other absorptive material to line the sample container, ensure it is dry before determining the initial mass of the sample container. 6.2. Place the test sample in th

10、e sample container. Determine and record the temperature of the test sample. To facilitate drying, evenly distribute the test sample in the sample container. 6.3. Determine and record the total mass of the sample container and moist test sample to the nearest 0.1 g. 6.4. Preheat the oven to drying t

11、emperature. The drying temperature shall fall within the job mix formula mixing temperature range. If a mixing temperature range is not supplied, a temperature of 163 14C (325 25F) will be used. Note 2For repeatability between operators and/or laboratories, the difference between drying temperatures

12、 for samples should not exceed 9C (15F). 6.5. Calculate the mass of the initial, moist test sample by subtracting the mass of the sample container determined in Section 6.1 from the total mass of the sample container and moist test sample determined in Section 6.3. 6.6. Dry the sample initially for

13、90 5 min and determine its mass. Then continue to dry the sample to constant mass, checking at 30 5-min intervals until further drying does not alter the mass by more than 0.05 percent. Note 3The moisture content of test samples and the number of test samples in the oven will affect the rate of dryi

14、ng at any given time. Placing wet test samples in the oven with nearly dry test samples could affect the drying process. 6.7. Cool the sample container and test sample to approximately the same temperature as determined in Section 6.2. 6.8. Determine and record the total mass of the sample container

15、 and dry test sample to the nearest 0.1 g. Note 4Do not attempt to remove the test sample from the sample container for the purposes of determining the dry mass of the test sample. 6.9. Calculate the mass of the final, dry test sample by subtracting the mass of the sample container determined in Sec

16、tion 6.1 from the total mass of the sample container and dry test sample determined in Section 6.8. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-2c T 329-3 AASHTO 7. CALCULATIONS 7.1. Calculate moi

17、sture content as follows: moisture content, % 100iffMMM= (1) where: Mi= mass of the initial, moist test sample, g; and Mf = mass of the final, dry test sample, g. Example: Mi = 1134.9 g Mf= 1127.3 g 1134.9 g 1127.3 gmoisture content, % 100 0.67%1127.3 g= = 7.2. Calculate the percent change in mass,

18、as described in Section 6.6, as follows: ( )% change 100pnnMMM= (2) where: Mp= previous mass measurement; and Mn= new mass measurement. 8. REPORT 8.1. Report the moisture content to the nearest 0.01 percent. 9. KEYWORDS 9.1. Hot mix asphalt; moisture content; oven-drying. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.