Question

The limit of aggregate crushing value for dense mix carpet in flexible pavements is .......

• A. 50
• B. 40
• C. 30
• D. 25

Hint:

For surface courses like Dense Mix Carpet, a lower ACV (less equal to 30%) ensures higher durability and better resistance to deformation under traffic loads.

Answer 1

The Correct Option is C

Step 1: Understanding Aggregate Crushing Value (ACV)
The Aggregate Crushing Value is a measure of the resistance of aggregates to crushing under gradually applied compressive load. It is expressed as a percentage by weight of the crushed material to the total weight of the sample.
Step 2: IRC Specification for Dense Mix Carpet (DMC)
As per Indian Roads Congress (IRC) and MORTH guidelines: - For high-quality bituminous surfacing such as Dense Mix Carpet (DMC), the maximum allowable ACV is 30%. - This ensures the aggregate is strong enough to withstand the high traffic and stress in the wearing course.
Step 3: Option Evaluation
- 50 → Too high; used for low-strength layers
- 40 → Higher than acceptable limit for surface layers
- 30 → Correct as per IRC for DMC
- 25 → Acceptable, but not specified as the upper limit
Step 4: Final Answer
Hence, the limit of ACV for dense mix carpet is 30.