15.4.2. Aggregate Gradation Control

Try these first

1. 1.

   What is aggregate gradation?

   Hint

   Think about what the composition of the aggregate could imply.

2. 2.

   Why are gradation control zones used?

   Hint

   Consider the effects of having the wrong proportions of particles.

3. 3.

   What is the primary purpose of controlling aggregate gradation in asphalt mixes?

   • To maximize material costs
   • To enhance stability and durability
   • To decrease weight

   Hint

   Focus on what properties gradation affects.

4. 4.

   True or False: Gradation plots can help engineers assess the distribution of particle sizes in an aggregate mix.

   • True
   • False

   Hint

   Think about the benefits of visual analysis.

5. 5.

   Given a mix design with an aggregate gradation failure, identify the probable causes and suggest how you would revise the mix to meet performance standards.

   Hint

   Consider how each size plays a role in pavement integrity.

6. 6.

   Create a plan for evaluating the performance of an asphalt mix using gradation plots. What steps would you include?

   Hint

   Think about the process from start to finish in evaluating mixes.