Active Standard ASTM D7870 / D7870M | Developed by Subcommittee: D04.22
Book of Standards Volume: 04.03
Significance and Use
3.1 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].
3.2 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.
3.3 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 Methods D6926 or D6752 for before and after conditioning, dynamic modulus, flow number, AASHTO TP 79 and visual inspection for stripped aggregates.
1.1 This practice includes procedures for preparing compacted asphalt mixture specimens, exposing the specimens to hydrostatic pore pressure inside an enclosed chamber and guidance on testing the specimens for the effect of water on the tensile strength or change in other properties of the asphalt mixture, such as density, modulus, etc.
1.2 Specimens conditioned according to this practice can be tested using methods and test procedures referenced in this document and those results may provide information as to the effect of the moisture conditioning of this practice on the moisture sensitivity of those mixtures.
1.3 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.
1.4 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 non-conformance with the standard.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D979 Practice for Sampling Bituminous Paving Mixtures
D1561 Practice for Preparation of Bituminous Mixture Test Specimens by Means of California Kneading Compactor
D2726 Test Method for Bulk Specific Gravity and Density of Non-Absorptive Compacted Bituminous Mixtures
D3665 Practice for Random Sampling of Construction Materials
D3666 Specification for Minimum Requirements for Agencies Testing and Inspecting Road and Paving Materials
D4013 Practice for Preparation of Test Specimens of Bituminous Mixtures by Means of Gyratory Shear Compactor
D4867 Test Method for Effect of Moisture on Asphalt Concrete Paving Mixtures
D5361 Practice for Sampling Compacted Bituminous Mixtures for Laboratory Testing
D6752 Test Method for Bulk Specific Gravity and Density of Compacted Bituminous Mixtures Using Automatic Vacuum Sealing Method
D6925 Test Method for Preparation and Determination of the Relative Density of Hot Mix Asphalt (HMA) Specimens by Means of the Superpave Gyratory Compactor
D6926 Practice for Preparation of Bituminous Specimens Using Marshall Apparatus
D6927 Test Method for Marshall Stability and Flow of Bituminous Mixtures
D6931 Test Method for Indirect Tensile (IDT) Strength of Bituminous Mixtures
AASHTO StandardsAASHTOTP79 Standard Method of Test for Determining the Dynamic Modulus and Flow Number for Hot Mix Asphalt (HMA) Using the Asphalt Mixture Performance Tester (AMPT)
ICS Number Code 75.140 (Waxes, bituminous materials and other petroleum products)
UNSPSC Code 30121600(Asphalts)