1、Standard Method of Test for Specific Gravity of Semi-Solid Asphalt Materials AASHTO Designation: T 228-09 (2013) ASTM Designation: D70-08 American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-2b T 228-1 AASHTO Standard M
2、ethod of Test for Specific Gravity of Semi-Solid Asphalt Materials AASHTO Designation: T 228-09 (2013) ASTM Designation: D70-08 AASHTO T 228-09 (2013) is identical to ASTM D70-08 except for the following provisions: 1. Replace all references to the ASTM standards listed in the following table with t
3、he corresponding AASHTO standards: Referenced Standards ASTM AASHTO D140 R 66 D3142 T 295 2. Add the following to Section 2: 2.3 AASHTO Standard: M 231, Weighing Devices Used in the Testing of Materials 3. Add the following sentence to Note 2: The terms “relative density” and “specific gravity” are
4、used interchangeably in this standard. 4. Replace Section 6.4 with the following: 6.4 Balanceconforming to the requirements of M 231, Class B. 5. Replace Section 11.2 with the following: 11.2 Fill the pycnometer with freshly boiled distilled or deionized water at test temperature and place the stopp
5、er in the pycnometer. Do not allow any air bubbles to remain in the pycnometer. Place the filled pycnometer in the beaker. 6. Replace the last sentence in Section 12.1 with the following: “Do not heat for more than 60 min over a flame or hot plate or for more than 2 h in an oven, and avoid incorpora
6、ting air bubbles in the sample.” 7. Replace Section 12.3 with the following: 12.3 Fill the pycnometer with freshly boiled distilled or deionized water at the test temperature and place the stopper in the pycnometer. Do not allow any air bubbles to remain in the pycnometer. Place the filled pycnomete
7、r in the beaker. 8. Replace Section 15 with the following: 15. Precision and Bias 15.1 PrecisionCriteria for judging the acceptability of the relative density results obtained by this method are given in Table 1. 15.1.1 Single-Operator Precision (Repeatability)The figures in Column 2 of Table 1 are
8、the standard deviations that have been found to be appropriate for the conditions of 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, should not be considered suspect unless the differenc
9、e in the two results exceeds the values given in Table 1, Column 3. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-2b T 228-2 AASHTO 15.1.2 Multilaboratory Precision (Reproducibility)The figures in C
10、olumn 4 of Table 1 are the standard deviations that have been found to be appropriate for the conditions of test described in Column 1. Two results submitted by two different operators testing the same material in different laboratories shall not be considered suspect unless the difference in the tw
11、o results exceeds the values given in Table 1, Column 5. Table 1Precision Estimates Single-Operator Multilaboratory Standard Deviation Acceptable Range of Two Results Standard Deviation Acceptable Range of Two Results Condition (1s)a(d2s)a(1s)a(d2s)aAsphalt: Specific Gravity (15.6C) 0.0011 0.0032 0.
12、0018 0.0051 Specific Gravity (25C) 0.0008b0.0021b0.0013b0.0035bSoft Tar Pitch: Specific Gravity (15.6C) 0.0013 0.0038 0.0029 0.0083 Specific Gravity (25C) 0.00083 0.0023 0.0017 0.0048 aThese values represent the 1s and d2s limits described in ASTM Practice C670. bThe precision estimates denoted by t
13、he superscript “b” are based on the analysis of test results from eight pairs of AMRL proficiency samples. The data analyzed consisted of results from 104 to 121 laboratories for each of the eight pairs of samples. The analysis included four binder grades: PG 52-34, PG 64-16, PG 64-22, and PG 70-22.
14、 Average specific gravities in the analysis ranged from 1.0058 to 1.0428. The details of this analysis are in the final report for NCHRP Project No. 9-26, Phase 3. Note: Values in Table 1 not marked with a superscript “b” are precision estimates retained from ASTM D70-03, Section 14, Table 1. These
15、values were not part of the scope of the AMRL research activities described with the superscript “b.” 15.2 BiasNo information can be presented on the bias of the procedure because no material having an accepted reference value is available. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.
