26. Marshall Mix Design

Try these first

1. 1.

   What is the main purpose of Marshall Mix Design?

   Hint

   Think about what bitumen does in asphalt.

2. 2.

   Name one property measured in Marshall Mix Design.

   Hint

   What do we measure when we apply load to the specimen?

3. 3.

   What is the purpose of the Marshall stability test?

   • To measure air voids
   • To determine maximum load
   • To mix aggregates

   Hint

   Think about what happens when a load is applied.

4. 4.

   True or False: Higher flow values are always desirable in asphalt mixtures.

   • True
   • False

   Hint

   Consider the risks associated with high flow.

5. 5.

   Given the stability and flow results from various trials, plot the data and identify the optimum bitumen content. Discuss how the graph represents the performance characteristics of the mix.

   Hint

   Pay attention to where the stability peaks and how it correlates with flow changes.

6. 6.

   Analyze a case where the air voids percentage dropped below the specified threshold and discuss potential failure points in pavement performance.

   Hint

   Link the effects of low air voids to durability issues.