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ASTM D4957-2018 pdf free download

ASTM D4957-2018 pdf free download.Standard Test Method for Apparent Viscosity of Asphalt Emulsion Residues and Non- Newtonian Asphalts by Vacuum Capillary Viscometer
1. Scope
1.1 This test method describes procedures primarily de- signed to determine the apparent viscosities of residues ob- tained by distilling asphalt emulsions according to Test Method D6997. It is also recommended for use on non-Newtonian asphalts at any temperature within the capability of the apparatus. This test method is useful in characterizing rheo- logical properties of non-Newtonian asphalts as a function of shear rate under the conditions of the test method. This test is run in straight open-end tube viscometers, normally at 60 °C, but is suitable for use at other temperatures. It is applicable over the range from 5 to 50 000 Pa·s. N OTE 1—The precision for this test method is based on determinations made at 60 °C. 1.2 The values stated in SI units are to be regarded as the standard, except in reference to viscometer constant or calibra- tion factor (K). 1.3 Warning—Mercury has been designated by the United States Environmental Protection Agency (EPA) and many state agencies as a hazardous material that can cause central nervous system, kidney, and liver damage. Mercury or its vapor may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products. See the applicable product Material Safety Data Sheets (MSDS) for details and the EPA’s website (www.epa.gov/mercury/faq.htm) for additional information. Users should be aware that selling mercury, mercury- containing products, or both, in your state may be prohibited by state law. 1.4 The text of this standard references notes and footnotes which provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard. 1.5 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 appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.6 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
3. Terminology
3.1 Definitions: 3.1.1 apparent viscosity—the determined viscosity obtained by the test method under description. Viscosity is the resistance to deformation or internal friction of a liquid expressed as the ratio of the shear stress to shear rate, whether this ratio is constant or not. The unit of viscosity obtained by dividing the shearing stress in N/m 2 by the rate of shear in reciprocal seconds is called the pascal second (Pa·s). The English unit of viscosity is the poise (P) with dimensions of 0.1N·s/m 2 (dynes/cm 2 /s), and is equivalent to 0.1 Pa·s.3.1.2 Newtonian liquid—a liquid in which the rate of shear is proportional to the shearing stress. The constant ratio of the shearing stress to rate of shear is the viscosity of the liquid. If the ratio is not constant, the liquid is non-Newtonian. N OTE 2—A power law fluid is a material in which the relation between the log ofthe shear stress is linear with the log ofthe shear rate. The slope of this relation is called the shear susceptibility, C. If C is less than unity, the material is classified as pseudoplastic and the apparent viscosity decreases with increased stress. If C is greater than one, the material is dilatant and the apparent viscosity increases with stress. If C is unity the material shows Newtonian flow. Most real materials show some non- Newtonian behavior and the apparent viscosity, computed as stress divided by the shear rate, is reported. 3.1.3 rheogram—a rheological diagram which shows how the apparent viscosity of a material varies with the shear rate. An apparent viscosity at a specific shear rate, normally 1 s −1 , can be estimated from this plot. A typical rheogram with an example is shown in Fig. 1.

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