【国外标准】 Standard Test Method for Specific Gravity, API Gravity, or Density of Cutback Asphalts by Hydrometer Method

5.1 Accurate determination of the density, specific gravity, or API gravity of cutback asphalts is necessary for the conversion of measured volumes to volumes at the standard temperature of 15 °C or 60 °F.5.2 Similarly, accurate determination is necessary for converting volumes to mass as required in other ASTM tests on cutback asphalts.5.3 Values corrected to 15 °C and 60 °F will be different because the two temperatures are not equal.1.1 This test method covers the laboratory determination, using a glass hydrometer, of the density, specific gravity, or API gravity of cutback asphalts as defined in Specifications D2026, D2027, and D2028 (Note 1). Values are measured on a hydrometer at convenient temperatures, readings of density, specific gravity, and API gravity being reduced to 15 °C or 60 °F by means of international standard tables. By means of these same tables, values determined in one of the three systems of measurement are convertible to equivalent values in either system so that measurements may be made in the units of local convenience.NOTE 1: This test method is applicable to cutback asphalts and in general follows, but provides more explicit routines than, the procedure outlined in Test Method D1298.1.2 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 7.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.