Which sieve size has the largest influence on the mixture's workability?

The #4 sieve has the largest influence on the mixture's workability because it is considered to be the separating point between fine aggregate and coarse aggregate in asphalt mixtures. The materials passing through the #4 sieve are finer particles that help fill the voids in the larger aggregates, which leads to improved packing and a more cohesive mix. When the proportion of particles passing through the #4 sieve is optimal, it enhances the mixture's ability to be compacted and worked with during the paving process, ultimately affecting its performance and durability.

In contrast, the components associated with larger sieve sizes, such as the #8 or #10 sieve, and even the #200 sieve, have less direct influence on workability since they contain either larger aggregate particles or dust particles that serve different roles in the overall mix design. While all sieve sizes play a role in the overall properties of the asphalt mix, it is the particles around the #4 sieve that primarily affect how easy or difficult it is to work with the mixture during installation.