Pick up the correct statement from the following
Correct Answer: D. All option are correct
📚 Detailed Explanation: Aggregate Impact Value (AIV) Limits
The Aggregate Impact Value (AIV) test, standardised under IS 2386 (Part IV), measures the resistance of aggregate to sudden impact loads. Different construction applications impose different impact severities and therefore require different AIV limits.
Why D (All option are correct) is correct:
Statement A — For general building concrete, aggregate with AIV ≤45% is acceptable. Buildings primarily experience sustained loads rather than sharp impacts, so a less stringent limit applies.
Statement B — For pavement and runway concrete, aggregate with AIV ≤30% is required. Pavements experience repetitive impact from vehicle wheels and aircraft loads, demanding tougher aggregate.
Statement C — The AIV test method is indeed standardised under IS 2386 (Part IV), which covers all mechanical tests for aggregates (AIV, ACV, LA abrasion).
Statement A — For general building concrete, aggregate with AIV ≤45% is acceptable. Buildings primarily experience sustained loads rather than sharp impacts, so a less stringent limit applies.
Statement B — For pavement and runway concrete, aggregate with AIV ≤30% is required. Pavements experience repetitive impact from vehicle wheels and aircraft loads, demanding tougher aggregate.
Statement C — The AIV test method is indeed standardised under IS 2386 (Part IV), which covers all mechanical tests for aggregates (AIV, ACV, LA abrasion).
AIV Limits by Application
| Application | Max AIV | Reason |
|---|---|---|
| General building concrete | ≤45% | Lower impact severity |
| Pavement / runway concrete | ≤30% | Repetitive wheel / aircraft impact |
| Wearing surface / heavy duty floor | ≤30% | Continuous abrasive traffic |
Key Concepts for Students
- AIV ≤45% for buildings, ≤30% for pavements — the most common way this test appears in exams.
- Lower AIV = tougher aggregate; a higher percentage means more material broke = less tough.
- AIV and ACV (Aggregate Crushing Value) often give similar results; both are defined under IS 2386 Part IV.