13.8. Factors Affecting Bituminous Mix Design

Try these first

1. 1.

   What does aggregate gradation influence in bituminous mixes?

   Hint

   Think about the relationship between sizes of particles.

2. 2.

   What is one common bitumen grade used in pavement?

   Hint

   Consider typical viscosity grades.

3. 3.

   What is the primary concern with poor aggregate gradation in a bituminous mix?

   • Increased air voids
   • Reduced strength
   • Higher cost

   Hint

   Think about what bad gradation means for the overall mix.

4. 4.

   True or False: The mixing temperature has no impact on the performance of the prepared bituminous mix.

   • True
   • False

   Hint

   Remember how temperature affects viscosity.

5. 5.

   Evaluate how different environmental conditions might impact the performance of a bituminous mix in a coastal area.

   Hint

   Think about how saltwater might affect standard bitumen.

6. 6.

   Propose a method to analyze the effects of air void content variations in existing pavements in a rainy climate.

   Hint

   Consider the role of drainage in pavement performance.