What characteristic is important for the angularity and distribution of particles in HMA?

The importance of particle angularity and distribution in Hot Mix Asphalt (HMA) relates directly to achieving the desired mechanical properties of the asphalt mix. When aggregates have angular particles, they are more likely to interlock with one another. This interlocking action increases the stability and strength of the asphalt mixture, enabling it to resist deformation under load.

The distribution of particle sizes also plays a critical role in filling the voids between larger aggregates, which contributes to a denser and more cohesive mix. A well-graded aggregate mix that combines different sizes enhances the overall performance of the HMA.

This characteristic also influences other performance-related aspects, such as resistance to cracking and rutting, making it vital in the design and application of asphalt pavements. Therefore, the effectiveness of the interlock due to the angularity and appropriate size distribution of the particles significantly enhances the structural integrity of the HMA.