If the compaction factor is 0.95, the workability of concrete is:
Correct Answer: D. High
📚 Detailed Explanation: Compaction Factor and Workability Classification
Why D (High) is correct: The Compacting Factor test (IS 5515 / IS 7320) classifies workability as follows:
• CF < 0.75: Very low workability
• CF 0.75–0.85: Low workability
• CF 0.85–0.92: Medium workability
• CF > 0.92: High workability
CF = 0.95 > 0.92, so the answer is High. Note: CF 0.92 is borderline. CF 0.95 comfortably classifies as high.
• CF < 0.75: Very low workability
• CF 0.75–0.85: Low workability
• CF 0.85–0.92: Medium workability
• CF > 0.92: High workability
CF = 0.95 > 0.92, so the answer is High. Note: CF 0.92 is borderline. CF 0.95 comfortably classifies as high.
Compaction Factor Classification
| Compaction Factor | Workability |
|---|---|
| < 0.75 | Very low |
| 0.75 – 0.85 | Low |
| 0.85 – 0.92 | Medium |
| > 0.92 (e.g., 0.95) | High |
- CF = weight of partially compacted / weight of fully compacted concrete. Higher CF = less air void = more workable.
- CF 0.95 → High workability.