Standard Practice for Moisture Conditioning Compacted Asphalt Mixture Specimens by Using Hydrostatic Pore Pressure

Importancia y uso:

4.1 This practice provides an accelerated conditioning method under cyclic loading. This system is capable of operating at higher than normal temperatures and creating pore pressure within a compacted asphalt mixture to achieve an acceleration of the effects that a mixture would experience over time from traffic at normal temperatures and conditions. The accelerated conditioning in this practice is intended to simulate the stresses induced in a wet pavement by a passing vehicle tire. The pulse shape produced by this system approximates a Lorentzian function with a half peak width of approximately 1 s at 276 kPa [40 psi].

4.2 The factors that influence the potential for moisture damage to occur include aggregate mineralogy, mixture air voids, water, cyclic applied stress, and elevated temperature. This practice provides a method and apparatus that is capable of producing three of these factors: water, stress, and high temperature. Aggregate mineralogy and air voids are mixture properties.

4.3 Specimens conditioned by this system can be tested using a variety of different tests, including Test Method D6931, Test Method D6927, bulk specific gravity difference obtained by Test Method D6926 or D6752/D6752M for before and after conditioning, dynamic modulus, flow number, AASHTO T 378, and visual inspection for stripped aggregates.

Note 1: The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Specification D3666 alone does not completely ensure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or some similar acceptance guideline provides a means of evaluating and controlling some of those factors.

Subcomité:

D04.22

Volúmen:

04.03

Número ICS:

75.140 (Waxes, bituminous materials and other petroleum products)

Palabras clave:

antistripping additives; asphalt concrete paving mixtures; cyclic stress; moisture; moisture conditioning; pore pressure; tensile strength; water;