ASTM D7405-20 PDF Download

ASTM D7405-20 is a standard test method that is used to determine the multiple stress creep and recovery (MSCR) of asphalt binders using a dynamic shear rheometer (DSR). This test method is designed to identify the presence of elastic response in a binder and the change in elastic response at two different stress levels. It is also used as a surrogate for other test methods that measure elasticity in asphalt binders.

The MSCR test is conducted at a specified temperature and can be performed on unaged material, material aged in accordance with various methods, or material aged using a combination of methods. The percent recovery obtained from this test is used to evaluate the presence of elastic response and the stress dependence of polymer-modified and unmodified asphalt binders.

It is important to note that the quality and reliability of the results obtained from this test method depend on the competence of the personnel performing the procedure and the calibration and maintenance of the equipment used. Therefore, compliance with the specified requirements alone does not guarantee reliable results, and additional factors need to be considered to ensure accurate testing.