In this test method a compacted sample is vacuum sealed inside a plastic bag. The density of the sample, SG1, is calculated using a water displacement method, with the sample sealed. With the sample still in water, the bag is cut open. Since the sample is under vacuum and the air voids are evacuated, water will rush in to fill all the water accessible air voids in the compacted sample. With the saturated weight of sample known, an apparent maximum density, SG2, can be calculated. The difference between SG2 and SG1 is the measure of the amount of water that has penetrated the compacted sample. This difference can be used to determine the fraction of total number of voids that are accessible to water, Effective Percent Porosity or Percent Effective Air Voids.
The results obtained from this method can be used to determine the percentage of total air voids in a compacted sample that can be filled with water through surface or interconnected paths within the sample. In general, Effective Percent Porosity should be less than total percent air voids.
This method can be used for 100 mm and 150 mm diameter cylindrical samples and cubical samples.
Область применения1.1 This test method covers the determination of effective porosity or effective air voids of compacted mixtures by the use of a vacuum sealing method.
1.2 This method can be used for compacted field and laboratory bituminous paving samples, as well as other compacted samples with well defined geometrical shapes, such as concrete cylinders, cored rocks, and metal samples.
1.3 The results of this test method can be used to determine the degree of interconnectivity of air voids within a sample and can be correlated to permeability of compacted bituminous paving mixture samples.
1.4 A multi-laboratory precision and bias statement for this standard has not been developed at this time. Therefore, this standard should not be used for acceptance or rejection of a material for purchasing purposes.
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 appropriate safety and health practices and determine the applicability of regulatory requirements prior to use.