What overall goal should be achieved through the process of gradation testing?

The primary goal of gradation testing is to determine the particle size distribution of aggregate materials used in asphalt mixtures. This testing is crucial because the gradation affects the workability, stability, and durability of the asphalt mixture. By analyzing the proportion of various particle sizes within a sample, engineers can ensure that the mixture will perform well under the expected loads and environmental conditions. Proper gradation leads to better packing of the aggregate, which can enhance the mechanical properties of the asphalt concrete, such as its resistance to deformation and its longevity.

While establishing compressive strength, ensuring proper material layering, and calculating asphalt content are all important aspects of asphalt technology, they do not specifically focus on the distribution of particle sizes which is the essence of what gradation testing accomplishes. Understanding particle size distribution allows for the optimization of the mix design and the achievement of desired performance characteristics in the final product.