AASHTO T315-12 pdf free download

AASHTO T315-12 pdf free download.Determining the Rheological Properties of Asphalt Binder Using a Dynamic Shear Rheometer (DSR).
3.2.9. oscillatory shear—refers to a type of loading in which a shear stress or shear strain is applied to a test sample in an oscillatory manner such that the shear stress or strain varies in amplitude by about zero in a sinusoidal manner.
3.2.10. parallel plate geometry—refers to a testing geometry in which the test sample is sandwiched between two relatively rigid parallel plates and subjected to oscillatory shear.
3.2.11. phase angle (ó)—the angle in radians between a sinusoidally applied strain and the resultant sinusoidal stress in a controlled-strain testing mode, or between the applied stress and the resultant strain in a controlled-stress testing mode.
3.2.12. portable ther,nometer—an electronic device that consists of a temperature detector (probe containing a thermocouple or resistive element), required electronic circuitry, and readout system.
3.2.13. reference ther,nometer—a NIST—traceable liquid-in-glass or electronic thermometer that is used as a laboratory standard.
3.2.14. steric hardening—see molecular association.
3.2.15. storage shear nodulus (G’)—the complex shear modulus multiplied by the cosine of the phase angle expressed in degrees. It represents the in-phase component of the complex modulus that is a measure of the energy stored during a loading cycle.
3.2.16. temperature correction—difference in temperature between the temperature indicated by the DSR and the test specimen as measured by the portable thermometer inserted between the test plates.
3.2.17. thermal equilibrium—is reached when the temperature of the test specimen mounted between the test plates is constant with time.
3.2.18. verjfIcation—process of checking the accuracy of a device or its components against an internal laboratory standard. It is usually performed within the operating laboratory.
4. SUMMARY OF TEST METHOD
4.1. This standard contains the procedure used to measure the complex shear modulus (G*) and phase angle (6) of asphalt binders using a dynamic shear rheometer and parallel plate test geometry.
4.2. The standard is suitable for use when the dynamic shear modulus varies between 100 Pa and
10 MPa. This range in modulus is typically obtained between 6 and 88°C at an angular frequency of 10 rad/s, dependent upon the grade, test temperature, and conditioning (aging) of the asphalt binder.
4.3. Test specimens 1 mm thick by 25 mm in diameter or 2 mm thick by 8 mm in diameter are formed between parallel metal plates. During testing, one of the parallel plates is oscillated with respect to the other at preselected frequencies and rotational deformation amplitudes (strain control) (or torque amplitudes [stress control]). The required stress or strain amplitude depends upon the value of the complex shear modulus of the asphalt binder being tested. The required amplitudes have been selected to ensure that the measurements are within the region of linear behavior.
4.4. The test specimen is maintained at the test temperature to within ±0.1°C by positive heating and cooling of the upper and lower plates or by enclosing the upper and lower plates in a thermally controlled environment or test chamber.
4.5. Oscillatory loading frequencies using this standard can range from 1 to 100 radls using a sinusoidal waveform. Specification testing is performed at a test frequency of 10 rad!s. The complex modulus (Q*) and phase angle () are calculated automatically as part of the operation of the rheometer using proprietary computer sofiware supplied by the equipment manufacturer.
5. SIGNIFICANCE AND USE
5.1. The test temperature for this test is related to the temperature experienced by the pavement in the geographical area for which the asphalt binder is intended to be used.
5.2. The complex shear modulus is an indicator of the stiffness or resistance of asphalt binder to deformation under load. The complex shear modulus and the phase angle define the resistance to shear deformation of the asphalt binder in the linear viscoelastic region.
5.3. The complex modulus and the phase angle are used to calculate performance-related criteria in accordance with M 320.AASHTO T315-12  pdf download.