AASHTO T 209-20 PDF Download

AASHTO T 209-20 is a standard method that provides guidelines for determining the theoretical maximum specific gravity (Gmm) and density of hot-mix asphalt (HMA). The test is conducted at a temperature of 25°C (77°F). It is important to note that the accuracy of the test results is highest when the samples used have aggregates that are fully coated with asphalt binder. Therefore, it is recommended to perform the test on samples that are close to the optimum asphalt binder content to ensure complete coating.

The purpose of determining Gmm and density of HMA is to assess the quality and compactability of asphalt mixes. The Gmm value represents the specific gravity of the solid material in the HMA sample, taking into account the void spaces between the aggregate particles. The density measurement provides information about the compactness of the asphalt mix, which is crucial for durability and performance.