What is a common test used for assessing the moisture susceptibility of asphalt mixtures?

The Tensile Strength Ratio (TSR) test is a widely accepted method used to evaluate the moisture susceptibility of asphalt mixtures. This test helps determine how well an asphalt mixture can resist stripping, which is the loss of adhesion between the asphalt binder and the aggregates in the presence of moisture. In the TSR test, samples of the asphalt mixture are subjected to a wetting process followed by a tensile strength evaluation. By comparing the tensile strengths of the wet and dry specimens, the TSR provides a clear indication of the mix's performance under moisture conditions.

This assessment is critical because moisture can significantly impact the durability and longevity of asphalt pavements. Ensuring that a mixture has a suitable TSR value helps ensure that the pavement remains resilient against moisture damage, contributing to a longer service life.

The other options listed, while important in asphalt testing, do not specifically assess moisture susceptibility. The Viscosity Test measures the flow properties of the asphalt binder, the Marshall Mix Design test evaluates the optimal asphalt content and performance characteristics of the mixture, and the Heat Resistance Test assesses how well the asphalt mixture can withstand high temperatures but does not focus on moisture-related issues.