Marshall Stability Test: The Process

The Marshall process uses a series of laboratory tests and evaluation criteria for selecting materials and to progressively narrow in on optimum mix design. A suitable mix will resist deformation from traffic loads and damage from climatic conditions and will have adequate skid resistance.

Aggregate Selection begins with lab testing to measure the physical properties of aggregates. Abrasion resistance, soundness, durability, and particle shape all combine to ensure the aggregates themselves are durable and will also contribute to the strength and resistance to deformation of the final asphalt mix. The chart below shows some typical laboratory tests performed for the evaluation of proposed aggregates. There are linked references for testing equipment and ASTM/AASHTO test methods.